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Hindawi Publishing CorporationJournal of Function Spaces and ApplicationsVolume 2013 Article ID 723976 13 pageshttpdxdoiorg1011552013723976
Research ArticleHeat Equations Associated with Weinstein Operator andApplications
Hatem Mejjaoli
Department of Mathematics College of Sciences Taibah University PO Box 30002 Al Madinah Al Munawarah Saudi Arabia
Correspondence should be addressed to HatemMejjaoli hatemmejjaoliipestrnutn
Received 31 May 2013 Accepted 3 August 2013
Academic Editor Dashan Fan
Copyright copy 2013 Hatem Mejjaoli This is an open access article distributed under the Creative Commons Attribution Licensewhich permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited
We establish a characterization for the homogeneous Weinstein-Besov spaces via the Weinstein heat semigroup Next we obtainthe generalized Sobolev embedding theorems
Dedicated to Khalifa Trimeche
1 Introduction
We consider the Weinstein operator defined on R119889times ]0infin[
by
Δ 120573 =
119889+1
sum
119894=1
1205972
1205971199092
119894
+
2120573 + 1
119909119889+1
120597
120597119909119889+1
120573 gt minus
1
2
= Δ 119889 +L120573
(1)
where Δ 119889 is the Laplacian for the 119889-first variables and L120573 isthe Bessel operator for the last variable given by
L120573 =
1205972
1205971199092
119889+1
+
2120573 + 1
119909119889+1
120597
120597119909119889+1
120573 gt minus
1
2
(2)
For 119889 gt 2 the operator Δ 120573 is the Laplace-Beltrami operatoron the Riemannian space R119889
times ]0infin[ equipped with thefollowing metric
1198891199042= 119909
2(2120573+1)(119889minus1)
119889+1
119889+1
sum
119894=1
1198891199092
119894(3)
(cf [1 2])TheWeinstein operatorΔ 120573 has several applicationsin pure and applied mathematics especially in the fluidmechanics (cf [3])
The harmonic analysis associated with the Weinsteinoperator is studied by Ben Nahia and Ben Salem (cf [1 2])In particular the authors have introduced and studied thegeneralized Fourier transform associated with the Weinsteinoperator This transform is called the Weinstein transformWe note that for this transform we have studied the uncer-tainty principle (cf [4]) and the Gabor transform (cf [5])
In the present paper we intend to continue our studyof generalized spaces of type Sobolev associated with theWeinstein operator that started in [6]
In this paper we consider the Weinstein heat equation
120597119905119906 minus Δ 120573119906 = 119891 (119905 119909) (119905 119909) isin (0infin) timesR119889+1
+
119906|119905=0 = 119892
(4)
We study (4) to focus on the following problems
(1) Characterize the homogeneous Weinstein-Besovspaces via the Weinstein heat semigroup
(2) Prove the imbedding Sobolev theorems
I have studied the generalized Sobolev spaces in thecontext of differential-differences operators (cf [7ndash10])
The remaining part of the paper is organized as followsSection 2 is a summary of the main results in the harmonicanalysis associatedwith theWeinstein operators In Section 3
2 Journal of Function Spaces and Applications
we introduce and study the homogeneous Weinstein-Besovspaces the homogeneous Weinstein-Triebel-Lizorkin spacesand the homogeneous Weinstein-Riesz potential spaces InSection 4 we characterize the homogeneousWeinstein Besovspaces via the Weinstein heat semigroup Next we prove theSobolev embedding theorems
2 Preliminaries
In order to confirm the basic and standard notations webriefly overview the Weinstein operator and the relatedharmonic analysis Main references are [1 2]
21 Harmonic Analysis Associated with the Weinstein Opera-tor In this subsection we collect some notations and resultson theWeinstein kernel theWeinstein intertwining operatorand its dual the Weinstein transform and the Weinsteinconvolution
In the following
R119889+1
+= R
119889times [0infin[
119909 = (1199091 119909119889 119909119889+1) = (1199091015840 119909119889+1) isin R
119889+1
+
119909 = radic1199092
1+ sdot sdot sdot + 119909
2
119889+1
(5)
We denote by 119862lowast(R119889+1
) the space of continuous functionson R119889+1 even with respect to the last variable 119862119901
lowast(R119889+1
) thespace of functions of class 119862119901 on R119889+1 even with respectto the last variable Elowast(R
119889+1) the space of 119862infin-functions on
R119889+1 even with respect to the last variable Slowast(R119889+1
) theSchwartz space of rapidly decreasing functions onR119889+1 evenwith respect to the last variable 119863lowast(R
119889+1) the space of 119862infin-
functions on R119889+1 which are of compact support even withrespect to the last variable S1015840
lowast(R119889+1
) the space of temperatedistributions on R119889+1 even with respect to the last variableIt is the topological dual of Slowast(R
119889+1)
We consider the Weinstein operator Δ 120573 defined by
forall119909 = (1199091015840 119909119889+1) isin R
119889times ]0infin[
Δ 120573119891 (119909) = Δ 1199091015840119891 (1199091015840 119909119889+1) +L120573119909
119889+1
119891 (1199091015840 119909119889+1)
119891 isin 1198622
lowast(R
119889+1)
(6)
where Δ 1199091015840 is the Laplace operator on R119889 and L120573119909119889+1
is theBessel operator on ]0infin[ given by
L120573119909119889+1
=
1198892
1198891199092
119889+1
+
2120573 + 1
119909119889+1
119889
119889119909119889+1
120573 gt minus
1
2
(7)
TheWeinstein kernel Λ is given by
Λ (119909 119911) = 119890119894⟨11990910158401199111015840⟩119895120573 (119909119889+1119911119889+1)
forall (119909 119911) isin R119889+1
times C119889+1
(8)
where 119895120573(119909119889+1119911119889+1) is the normalized Bessel function TheWeinstein kernel satisfies the following properties
(i) For each 119911 isin R119889+1
+ we have
Δ 120573Λ (119909 119911) = minus1199112Λ (119909 119911) forall119909 isin R
119889+1
+ (9)
(ii) For all 119911 119905 isin C119889+1 we have
Λ (119911 119905) = Λ (119905 119911) Λ (119911 0) = 1
Λ (120582119911 119905) = Λ (119911 120582119905) forall120582 isin C(10)
(iii) For all ] isin N119889+1 119909 isin R119889+1 and 119911 isin C119889+1 we have1003816100381610038161003816119863
]119911Λ (119909 119911)
1003816100381610038161003816le 119909
|]| exp (119909 Im 119911) (11)
where 119863]119911= 120597
](120597119911
]1
1sdot sdot sdot 120597119911
]119889+1
119889+1) and |]| = ]1 + sdot sdot sdot + ]119889+1 In
particular1003816100381610038161003816Λ (119909 119910)
1003816100381610038161003816le 1 forall119909 119910 isin R
119889+1 (12)
The Weinstein intertwining operator is the operator R120573
defined on 119862lowast(R119889+1
) by
R120573119891 (1199091015840 119909119889+1)
=
2Γ (120573 + 1)
radic120587Γ (120573 + 12)
119909minus2120573
119889+1
timesint
119909119889+1
0
(1199092
119889+1minus 119905
2)
120573minus12
119891 (1199091015840 119905) 119889119905 119909119889+1 gt 0
119891 (1199091015840 0) 119909119889+1 = 0
(13)
R120573 is a topological isomorphism from Elowast(R119889+1
) ontoitself satisfying the following transmutation relation
Δ 120573 (R120573119891) = R120573 (Δ 119889+1119891) forall119891 isin Elowast (R119889+1
) (14)
where Δ 119889+1 = sum119889+1
119895=11205972
119895is the Laplacian on R119889+1
We denote by119871119901120573(R119889+1
+) the space ofmeasurable functions
on R119889+1
+such that
10038171003817100381710038171198911003817100381710038171003817119871119901
120573(R119889+1+
)= (int
R119889+1+
1003816100381610038161003816119891 (119909)
1003816100381610038161003816
119901119889120583120573 (119909))
1119901
lt infin
if 1 le 119901 lt infin
10038171003817100381710038171198911003817100381710038171003817119871infin120573(R119889+1+
)= ess sup
119909isinR119889+1+
1003816100381610038161003816119891 (119909)
1003816100381610038161003816lt infin
(15)
where 119889120583120573 is the measure on R119889+1
+given by
119889120583120573 (1199091015840 119909119889+1) = 119909
2120573+1
119889+1119889119909
1015840119889119909119889+1
(16)
TheWeinstein transform is given for 119891 in 1198711120573(R119889+1
+) by
F119882 (119891) (119910) = int
R119889+1+
119891 (119909)Λ (minus119909 119910) 119889120583120573 (119909) forall119910 isin R119889+1
+
(17)
Some basic properties of this transform are as follows
Journal of Function Spaces and Applications 3
(i) For 119891 in 1198711120573(R119889+1
+)
1003817100381710038171003817F119882 (119891)
1003817100381710038171003817119871infin120573(R119889+1+
)le100381710038171003817100381711989110038171003817100381710038171198711120573(R119889+1+
) (18)
(ii) For 119891 in Slowast(R119889+1
) we have
F119882 (Δ 120573119891) (119910) = minus10038171003817100381710038171199101003817100381710038171003817
2F119882 (119891) (119910) forall119910 isin R
119889+1
+ (19)
(iii) For all 119891 in 1198711120573(R119889+1
+) ifF119882(119891) belongs to 119871
1
120573(R119889+1
+)
then
119891 (119910) = 119862 (120573)int
R119889+1+
F119882 (119891) (119909) Λ (119909 119910) 119889120583120573 (119909) ae
(20)
where
119862 (120573) =
1
1205871198894120573+1198892
(Γ (120573 + 1))2 (21)
(iv) For 119891 isin Slowast(R119889+1
) if we define
F119882 (119891) (119910) = F119882 (119891) (minus119910) (22)
then
(F119882)minus1=
1
119862 (120573)
F119882 (23)
Proposition 1 (see [2]) (i) the Weinstein transform F119882 is atopological isomorphism fromSlowast(R
119889+1) onto itself and for all
f in Slowast(R119889+1
)
int
R119889+1+
1003816100381610038161003816119891 (119909)
1003816100381610038161003816
2119889120583120573 (119909) = 119862 (120573)int
R119889+1+
1003816100381610038161003816F119882 (119891) (120585)
1003816100381610038161003816
2119889120583120573 (120585)
(24)
(ii) In particular the renormalized Weinstein transform119891 rarr 119862(120573)
12F119882(119891) can be uniquely extended to an isometric
isomorphism from 1198712
120573(R119889+1
+) onto itself
In the Fourier analysis the translation operator is givenby 119891 997891rarr 119891(sdot + 119909)
In harmonic analysis associated for the operator Δ 120573 thegeneralized translation operator 120591119909 119909 isin R119889+1
+is defined by
forall119910 isin R119889+1
+
120591119909119891 (119910) =
Γ (120573 + 1)
radic120587Γ (120573 + 12)
times int
120587
0
119891(1199091015840+ 119910
1015840 radic119909
2
119889+1+ 119910
2
119889+1+ 2119909119889+1119910119889+1 cos 120579)
times (sin 120579)2120573119889120579(25)
where 119891 isin 119862lowast(R119889+1
)
By using the Weinstein kernel we can also define ageneralized translation For functions 119891 isin Slowast(R
119889+1) and
119910 isin R119889+1
+the generalized translation 120591119910119891 is defined by the
following relation
F119882 (120591119910119891) (119909) = Λ (119909 119910)F119882 (119891) (119909) (26)
By using the generalized translation we define the general-ized convolution product119891lowast
119882119892 of functions119891 119892 isin 1198711
120573(R119889+1
+)
as follows
119891lowast119882119892 (119909) = int
R119889+1+
120591119909119891 (minus1199101015840 119910119889+1) 119892 (119910) 119889120583120573 (119910) (27)
This convolution is commutative and associative and itsatisfies the following
(i) For all 119891 119892 isin 1198711
120573(R119889+1
+) 119891lowast119882 119892 belongs to 1198711
120573(R119889+1
+)
and
F119882 (119891lowast119882119892) = F119882 (119891)F119882 (119892) (28)
(ii) Let 1 le 119901 119902 119903 le infin such that 1119901 + 1119902 minus 1119903 = 1If 119891 isin 119871
119901
120573(R119889+1
+) and 119892 isin 119871
119902
120573(R119889+1
+) then 119891lowast119882119892 isin
119871119903
120573(R119889+1
+) and
1003817100381710038171003817119891lowast119882119892
1003817100381710038171003817119871119903120573(R119889+1+
)le10038171003817100381710038171198911003817100381710038171003817119871119901
120573(R119889+1+
)
10038171003817100381710038171198921003817100381710038171003817119871119902
120573(R119889+1+
) (29)
We define the tempered distribution T119891 associated with119891 isin 119871
119901
120573(R119889+1
+) by
⟨T119891 120601⟩ = int
R119889+1+
119891 (119909) 120601 (119909) 119889120583120573 (119909) (30)
for 120601 isin Slowast(R119889+1
) and denote by ⟨119891 120601⟩120573 the integral in therighthand side
Definition 2 The Weinstein transform F119882(120591) of a distribu-tion 120591 isin S1015840
lowast(R119889+1
) is defined by
⟨F119882 (120591) 120601⟩ = ⟨120591F119882 (120601)⟩ (31)
for 120601 isin Slowast(R119889+1
)
In particular for 119891 isin 119871119901
120573(R119889+1
+) it follows that for 120601 isin
Slowast(R119889+1
)
⟨F119882 (119891) 120601⟩ = ⟨F119882 (T119891) 120601⟩ = ⟨T119891F119882 (120601)⟩
= ⟨119891F119882 (120601)⟩120573
(32)
Proposition 3 The Weinstein transform F119882 is a topologicalisomorphism from S1015840
lowast(R119889+1
) onto itself
Definition 4 The generalized convolution product of a dis-tribution 119878 in S1015840
lowast(R119889+1
) and a function 120601 in Slowast(R119889+1
) is thefunction 119878lowast119882120601 defined by
119878lowast119882 120601 (119909) = ⟨119878119910 120591minus119910120601 (119909)⟩ (33)
4 Journal of Function Spaces and Applications
Proposition 5 Let 119891 be in 119871119901
120573(R119889+1
+) 1 le 119901 le infin and 120601
in Slowast(R119889+1
) Then the distribution T119891lowast119882120601 is given by thefunction 119891lowast119882120601 and T119891lowast119882120601 belongs to 119871119901
120573(R119889+1
+) Moreover
for all 120595 isin Slowast(R119889+1
)
⟨T119891lowast119882120601 120595⟩ = ⟨
119891 120601lowast119882 ⟩120573 (34)
where (119909) = 120595(minus119909) and
F119882 (T119891lowast119882 120601) = F119882 (T119891)F119882 (120601) (35)
For each 119906 isin S1015840
lowast(R119889+1
) we define the distribution Δ 120573119906
by ⟨Δ 120573119906 120595⟩ = ⟨119906 Δ 120573120595⟩ and this distribution satisfies thefollowing property
F119882 (Δ 120573119906) = minus10038171003817100381710038171199101003817100381710038171003817
2F119882 (119906) (36)
In the following we denote T119891 given by (30) by 119891 forsimplicity
3 B119904120573
119901119902 F119904120573
119901119902(R119889+1
+) H119904
119901120573Spaces and
Basic Properties
31 HomogeneousWeinstein-Littlewood-Paley DecompositionOne of the main tools in this paper is the homogeneousLittlewood-Paley decomposition of distribution associatedwith theWeinstein operators into dyadic blocs of frequencies
Lemma6 One defines byC the ring of center 0 of small radius12 and great radius 2 There exists two radial functions 120595 and120593 the values of which are in the interval [0 1] belonging to119863lowast(R
119889+1) such that
supp120595 sub 119861 (0 1) supp120593 sub C
forall120585 isin R119889+1
120595 (120585) + sum
119895ge0
120593 (2minus119895120585) = 1
forall120585 isin C sum
119895isinZ
120593 (2minus119895120585) = 1
|119899 minus 119898| ge 2 997904rArr supp120593 (2minus119899sdot) cap supp120593 (2minus119898sdot) = 0
119895 ge 1 997904rArr supp120595 cap supp120593 (2minus119895sdot) = 0
(37)
Notations We denote by
Δ 119895119891 = Fminus1
119882(120593(
120585
2119895)F119882 (119891))
119878119895119891 = sum
119899le119895minus1
Δ 119899119891 forall119895 isin Z(38)
The distribution Δ 119895119891 is called the 119895th dyadic block of thehomogeneous Littlewood-Paley decomposition of 119891 associ-ated with the Weinstein operators
Throughout this paper we define 120601 and 120594 by 120601 = Fminus1
119882(120593)
and 120594 = Fminus1
119882(120595)
When dealing with the Littlewood-Paley decompositionit is convenient to introduce the functions and 120593 belongingto119863lowast(R
119889+1) such that equiv 1 on supp120595 and 120593 equiv 1 on supp120593
Remark 7 We remark that
F119882 (119878119895119891) (120585) = (
120585
2119895)F119882 (119878119895119891) (120585)
F119882 (Δ 119895119891) (120585) = 120593(
120585
2119895)F119882 (Δ 119895119891) (120585)
(39)
We put
120601 = F
minus1
119882(120593) 120594 = F
minus1
119882() (40)
Definition 8 One denotes by S1015840
ℎ120573lowast(R119889+1
) the space oftempered distribution such that
lim119895rarrminusinfin
119878119895119906 = 0 in S1015840
lowast(R
119889+1) (41)
Proposition 9 (Bernstein inequalities) For all 120583 isin N119889+1 and120590 isin R for all 119895 isin Z for all 1 le 119901 119902 le infin and for all119891 isin S1015840
lowast(R119889+1
) one has the following
(i) 10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119902
120573(R119889+1+
)
le
10038171003817100381710038171003817
120601
10038171003817100381710038171003817119871119903120573(R119889+1+
)
10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119901
120573(R119889+1+
)2119895(119889+2120573+2)(1119901minus1119902)
with 1
119902
=
1
119901
+
1
119903
minus 1
(ii) 10038171003817100381710038171003817119878119895119891
10038171003817100381710038171003817119871119902
120573(R119889+1+
)
le10038171003817100381710038171205941003817100381710038171003817119871119903120573(R119889+1+
)
10038171003817100381710038171003817119878119895119891
10038171003817100381710038171003817119871119901
120573(R119889+1+
)2119895(119889+2120573+2)(1119901minus1119902)
with 1
119902
=
1
119901
+
1
119903
minus 1
(iii)1003817100381710038171003817100381710038171003817
(radicminusΔ 120573)
120590
Δ 119895119891
1003817100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)
le
10038171003817100381710038171003817F
minus1
119882(10038171003817100381710038171205851003817100381710038171003817
120590120593)
100381710038171003817100381710038171198711120573(R119889+1+
)
times
10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119901
120573(R119889+1+
)2119895120590
(42)
Proof Using Remark 7 we deduce from Proposition 5 that
119878119895119891 = 2119895(119889+2120573+2)
120594 (2119895sdot) lowast119882119878119895119891
Δ 119895119891 = 2119895(119889+2120573+2)
120601 (2119895sdot) lowast119882Δ 119895119891
(43)
Thus from the relation (29) we prove (i) (ii) and (iii)
32 Definitions In the following we define analogues of thehomogeneous Besov Triebel-Lizorkin and Riesz potentialspaces associated with the Weinstein operators on R119889+1
+and
obtain their basic propertiesFrom now we make the convention that for all non-
negative sequence 119886119902119902isinZ the notation (sum119902119886119903
119902)1119903 stands for
sup119902119886119902 in the case 119903 = infin
Journal of Function Spaces and Applications 5
Definition 10 Let 119904 isin R and 119901 119902 isin [1infin]The homogeneousWeinstein-Besov spaces B
119904120573
119901119902(R119889+1
+) are the spaces of distri-
bution in S1015840
ℎ120573lowast(R119889+1
) such that
10038171003817100381710038171198911003817100381710038171003817B119904120573
119901119902(R119889+1+
)= (sum
119895isinZ
(211990411989510038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119902
)
1119902
lt infin (44)
Proposition 11 (see [6]) Let 119904 isin R and 119901 and 119902 two elementsof [1infin] the space B
119904120573
119901119902(R119889+1
+) is the set of 119891 isin S1015840
ℎ120573lowast(R119889+1
)
verifying
10038171003817100381710038171003817
119891
10038171003817100381710038171003817B119904120573
119901119902(R119889+1+
)= (int
infin
0
(119905minus1199041003817100381710038171003817119891lowast119882120601119905
1003817100381710038171003817119871119901
120573(R119889+1+
))
119902119889119905
119905
)
1119902
lt infin
(45)
where 120601119905(119909) = (11199052120573+2+119889
)120601(119909119905) for all 119905 isin (0infin) and 119909 isin
R119889+1
+
Definition 12 For 119904 isin R and 119901 119902 isin [1infin] one writes10038171003817100381710038171198911003817100381710038171003817119861119904120573
119901119902(R119889+1+
)=10038171003817100381710038171198780119891
1003817100381710038171003817119871119901
120573(R119889+1+
)
+ (sum
119895ge1
(211990411989510038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119902
)
1119902
(46)
The nonhomogeneous Besov space 119861119904120573119901119902(R119889+1
+) associated
with the Weinstein operators is defined by
119861119904120573
119901119902(R
119889+1
+) = 119891 isin S
1015840(R
119889)
10038171003817100381710038171198911003817100381710038171003817119861119904120573
119901119902(R119889+1+
)lt infin (47)
We give now another definition equivalent to the nonho-mogeneous Besov space 119861119904120573119901119902(R119889+1
+)
Proposition 13 Let 119904 isin R and119901 and 119902 two elements of [1infin]the space 119861119904120573119901119902(R119889+1
+) is the set of 119891 isin S1015840
(R119889) verifying
10038171003817100381710038171003817
119891
10038171003817100381710038171003817119861119904120573
119901119902(R119889+1+
)=1003817100381710038171003817119891lowast119882120595
1003817100381710038171003817119871119901
120573(R119889+1+
)
+ (int
1
0
(119905minus1199041003817100381710038171003817119891lowast119882120601119905
1003817100381710038171003817119871119901
120573(R119889+1+
))
119902119889119905
119905
)
1119902
lt infin
(48)
Definition 14 Let 119904 isin R and 1 le 119901 119902 le infin the homogeneousWeinstein-Triebel-Lizorkin space F
119904120573
119901119902(R119889+1
+) is the space of
distribution in S1015840
ℎ120573lowast(R119889+1
) such that
10038171003817100381710038171198911003817100381710038171003817F119904120573
119901119902(R119889+1+
)=
100381710038171003817100381710038171003817100381710038171003817100381710038171003817
(sum
119895isinZ
211990411989511990210038161003816100381610038161003816Δ 119895119891
10038161003816100381610038161003816
119902
)
1119902100381710038171003817100381710038171003817100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)
lt infin (49)
Definition 15 For 119904 isin R the operatorR119904
120573from S1015840
ℎ120573lowast(R119889+1
)
to S1015840
ℎ120573lowast(R119889+1
) is defined by
R119904
120573(119891) = F
minus1
119882(sdot
119904F119882119891) (50)
The operatorRminus119904
120573is called Weinstein-Riesz potential space
Definition 16 For 119904 isin R and 1 le 119901 le infin the homogeneousWeinstein-Riesz potential space H119904
119901120573(R119889+1
+) is defined
as the space Rminus119904
120573(119871
119901
120573(R119889+1
+)) equipped with the norm
119891H119904119901120573(R119889+1+
)= R119904
120573(119891)
119871119901
120573(R119889+1+
)
Proposition 17 Let 119904 isin R and 1 le 119901 119902 le infinThe operator Δ 120573 is a linear continuous operator from
B119904120573
119901119902(R119889+1
+) into B
119904minus2120573
119901119902 (R119889+1
+) and from H119904
119901120573(R119889+1
+) into
H119904minus2
119901120573(R119889+1
+)
Proof We obtain these results by the similar ideas used in thenonhomogeneous case (cf [6])
Proposition 18 Let 119904 119905 isin R and 1 le 119901 119902 le infin The operatorR119905
120573is a linear continuous injective operator from B
119904120573
119901119902(R119889+1
+)
onto B119904minus119905120573
119901119902 (R119889+1
+) and from H119904
119901120573(R119889+1
+) onto H119904minus119905
119901120573(R119889+1
+)
Proof We obtain these results by the similar ideas used in thenonhomogeneous case (cf [6])
33 Embeddings As in the Euclidean case (cf [11]) themono-tone character of 119897119902-spaces and the Minkowskis inequalityyield the following
Proposition 19 If 1 le 1199021 lt 1199022 le infin one has
B119904120573
1199011199021
(R119889+1
+) 997893rarr
B119904120573
1199011199022
(R119889+1
+) (1 le 119901 le infin 119904 isin R)
(51)
MoreoverB119904120573
1199011(R
119889+1
+) 997893rarr
H119904
119901120573(R
119889+1
+) 997893rarr
B119904120573
119901infin(R
119889+1
+)
(1 le 119901 le infin 119904 isin R)
(52)
If 1199040 = 1199041 one also has
(H1199040
119901120573(R
119889+1
+)
H1199041
119901120573(R
119889+1
+))
120579119902=
B119904120573
119901119902(R
119889+1
+)
(1 le 119901 119902 le infin 120579 isin (0 1))
(53)
where 119904 = (1 minus 120579)1199040 + 1205791199041
Proposition 20 One assumes that 119904 minus (119889 + 2120573 + 2)119901 = 1199041 minus
(119889 + 2120573 + 2)1199011 Then the following inclusion holds
B119904120573
119901119902(R
119889+1
+) 997893rarr
B1199041120573
11990111199021
(R119889+1
+)
(1 le 119901 le 1199011 le infin 1 le 119902 le 1199021 le infin 119904 1199041 isin R)
(54)
Proof In order to prove the inclusion we use the estimate
Δ 119895119891 = 2119895(119889+2120573+2)
120601 (2119895sdot) lowast119882Δ 119895119891 (55)
Proposition 9(i) gives that10038171003817100381710038171003817Δ 119895119891
100381710038171003817100381710038171198711199011
120573(R119889+1+
)=
100381710038171003817100381710038172119895(119889+2120573+2)
120601 (2119895sdot) lowast119882Δ 119895119891
100381710038171003817100381710038171198711199011
120573(R119889+1+
)
le 1198622119895(119889+2120573+2)(1119901minus1119901
1)10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
(56)
6 Journal of Function Spaces and Applications
By definition of the homogeneous Weinstein-Besov spaceswe therefore infer10038171003817100381710038171198911003817100381710038171003817B1199041120573
11990111199021(R119889+1+
)
= (
infin
sum
119895=minusinfin
(2119895119904110038171003817100381710038171003817Δ 119895119891
100381710038171003817100381710038171198711199011
120573(R119889+1+
))
1199021
)
11199021
le 119862(sum
119895isinZ
(211989511990412119895(119889+2120573+2)(1119901minus1119901
1)10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
1199021
)
11199021
le 119862(sum
119895isinZ
(211989511990410038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
1199021
)
11199021
le 11986210038171003817100381710038171198911003817100381710038171003817B119904120573
119901119902(R119889+1+
)
(57)
since 119902 le 1199021 This gives the inclusion
Proposition 21 (1) If 119906 belongs to B119904120573
119901119902(R119889+1
+) cap
B119905120573
119901119902(R119889+1
+)
then 119906 belongs to B120579119904+(1minus120579)119905120573
119901119902 (R119889+1
+) for all 120579 isin [0 1] and
119906B120579119904+(1minus120579)119905120573
119901119902(R119889+1+
)le 119906
120579
B119904120573
119901119902(R119889+1+
)119906
1minus120579
B119905120573
119901119902(R119889+1+
) (58)
(2) If 119906 belongs to B119904120573
119901infin(R119889+1
+) cap
B119905120573
119901infin(R119889+1
+) and 119904 lt 119905
then 119906 belongs to B120579119904+(1minus120579)119905120573
1199011(R119889+1
+) for all 120579 isin (0 1) and there
exists a positive constant 119862(119905 119904) such that
119906B120579119904+(1minus120579)119905120573
1199011(R119889+1+
)le 119862 (119905 119904) 119906
120579
B119904120573
119901infin(R119889+1+
)119906
1minus120579
B119905120573
119901infin(R119889+1+
) (59)
(3) If 119906 belongs to B119904120573
119901infin(R119889+1
+) cap
B119904+120576120573
119901infin (R119889+1
+) and 120576 gt
0 then 119906 belongs to B119904120573
1199011(R119889+1
+) and there exists a positive
constant 119862 such that
119906B119904120573
1199011(R119889+1+
)le
119862
120576
119906B119904120573
119901infin(R119889+1+
)log
2(119890 +
119906B119904+120576120573
119901infin(R119889+1+
)
119906B119904120573
119901infin(R119889+1+
)
)
(60)
Proof (1) is obvious from the Holderrsquos inequality As for (2)we write 119906
B120579119904+(1minus120579)119905120573
1199011(R119889+1+
)as
sum
119895le119873
2119895(120579119904+(1minus120579)119905)10038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)+ sum
119895gt119873
2119895(120579119904+(1minus120579)119905)10038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
(61)
where 119873 is chosen here after By the definition of thehomogeneous Weinstein-Besov norms we see that
2119895(120579119904+(1minus120579)119905)10038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 2
119895(1minus120579)(119905minus119904)119906
B119904120573
119901infin(R119889+1+
)
2119895(120579119904+(1minus120579)119905)10038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 2
minus119895120579(119905minus119904)119906
B119905120573
119901infin(R119889+1+
)
(62)
and thus 119906B120579119904+(1minus120579)119905120573
1199011(R119889+1+
)is dominated by
119906B119904120573
119901infin(R119889+1+
)sum
119895le119873
2119895(1minus120579)(119905minus119904)
+ 119906B119905120573
119901infin(R119889+1+
)sum
119895gt119873
2minus119895120579(119905minus119904)
le 119862119906B119904120573
119901infin(R119889+1+
)
2(119873+1)(1minus120579)(119905minus119904)
2(1minus120579)(119905minus119904)
minus 1
+ 119906B119905120573
119901infin(R119889+1+
)
2minus119873120579(119905minus119904)
1 minus 2minus120579(119905minus119904)
(63)
Hence in order to complete the proof of (2) it suffices tochoose119873 such that
119906B119905120573
119901infin(R119889)
119906B119904120573
119901infin(R119889)
le 2119873(119905minus119904)
lt 2
119906B119905120573
119901infin(R119889)
119906B119904120573
119901infin(R119889)
(64)
As for (3) it is easy to see that 119906B119904120573
1199011(R119889+1+
)is dominated as
sum
119895le119873minus1
211989511990410038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)+ sum
119895ge119873
211989511990410038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
le (119873 + 1) 119906B119904120573
119901infin(R119889+1+
)+
2minus(119873minus1)120576
2120576minus 1
119906B119904+120576120573
119901infin(R119889+1+
)
(65)
Hence letting
119873 = 1 + [
[
1
120576
log2
119906B119904+120576120573
119901infin(R119889+1+
)
119906B119904120573
119901infin(R119889+1+
)
]
]
(66)
we can obtain the desired estimate
Proposition 22 Let 119902 isin (1infin) and let 119904 isin R such that0 lt 119904 lt (119889 + 2120573 + 2)119902 then one has
B119904120573
119902119902(R
119889+1
+) =
F119904120573
119902119902(R
119889+1
+) 997893rarr
F119904120573
119902infin(R
119889+1
+)
997893rarrF119904minus((119889+2120573+2)119902)120573
infininfin(R
119889+1
+)
(67)
H119904
119902120573(R
119889+1
+) =
F119904120573
1199022(R
119889+1
+) 997893rarr
F119904120573
119902infin(R
119889+1
+)
997893rarrF119904minus((119889+2120573+2)119902)120573
infininfin(R
119889+1
+)
(68)
Proof We obtain these results by the similar ideas used in thenonhomogeneous case (cf [6])
Theorem 23 Let 119886 119887 gt 0 and let 1199021 1199022 isin [1infin] Let120579 = 119886(119886 + 119887) isin (0 1) and let 1119901 = (1 minus 120579)1199021 +
1205791199022 Then there exists a constant 119862 such that for every119891 isin
F119886120573
1199021infin(R119889+1
+) cap
Fminus119887120573
1199022infin(R119889+1
+) then one has
1003816100381610038161003816119891 (119909)
1003816100381610038161003816le 119862(sup
119895isinZ
2119886119895 10038161003816100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
1minus120579
(sup119895isinZ
2minus119887119895 10038161003816
100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
120579
(69)
In particular one gets
10038171003817100381710038171198911003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
10038171003817100381710038171198911003817100381710038171003817
1minus120579
F119886120573
1199021infin(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
120579
Fminus119887120573
1199022infin(R119889+1+
) (70)
Journal of Function Spaces and Applications 7
Proof Let 119891 be a Schwartz class we have
1003816100381610038161003816119891 (119909)
1003816100381610038161003816le sum
119895isinZ
10038161003816100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816
le sum
119895isinZ
min(2minus119886119895sup119895isinZ
(2119886119895 10038161003816100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
2119895119887sup119895isinZ
(2minus119895119887 10038161003816
100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816))
(71)
We define119873(119909) as the largest index such that
2119895119887sup119895isinZ
(2minus119895119887 10038161003816
100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816) le 2
minus119886119895sup119895isinZ
(2119886119895 10038161003816100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816) (72)
and we write1003816100381610038161003816119891 (119909)
1003816100381610038161003816le sum
119895le119873(119909)
2119895119887sup119895isinZ
(2minus119895119887 10038161003816
100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
+ sum
119895gt119873(119909)
2minus119886119895sup
119895
(2119886119895 10038161003816100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
le 119862(sup119895isinZ
2119886119895 10038161003816100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
119887(119886+119887)
times (sup119895isinZ
2minus119887119895 10038161003816
100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
119886(119886+119887)
(73)
Thus (69) is proved In order to obtain (70) it is enough toapply the Holder inequality in the expression above since wehave 120579 = 119886(119886+119887) isin (0 1) and let 1119901 = (1minus120579)1199021+1205791199022
Corollary 24 Let 119902 isin (1infin) and let 119904 isin R such that 0 lt 119904 lt
(119889 + 2120573 + 2)119902 then one has
10038171003817100381710038171198911003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
10038171003817100381710038171198911003817100381710038171003817
1minus(119902119901)
Bminus((2120573+2+119889)119902minus119904)120573
infininfin (R119889+1
+ )
10038171003817100381710038171198911003817100381710038171003817
119902119901
B119904120573
119902119902(R119889+1
+ )
(74)
10038171003817100381710038171198911003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
10038171003817100381710038171198911003817100381710038171003817
1minus(119902119901)
Bminus((2120573+2+119889)119902minus119904)120573
infininfin (R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
119902119901
H119904119902120573(R119889+1+
) (75)
where 119901 = 119902(2120573 + 2 + 119889)(2120573 + 2 + 119889 minus 119902119904)
Proof By choosing 119886 = 119904 gt 0 minus119887 = 119904 minus (119889 + 2120573 + 2)119902 lt 01199021 = 119902 and 1199022 = infin we deduce (74) from the relations (70)and (67) In the same way we deduce (75) from the relations(70) and (68)
4 Generalized Heat Equation
41 Characterization for the Weinstein-Besov Spaces TheWeinstein heat equation reads
120597119905119906 (119905 119909) minus Δ 120573119906 (119905 119909) = 119891 (119905 119909) (119905 119909) isin [0infin) timesR119889+1
+
119906|119905=0 = 119892
(76)
We introduce the Weinstein heat semigroup 119867120573(119905) for theWeinstein-Laplace operator
119867120573 (119905) 119892 (119909) =
int
R119889+1+
Γ120573 (119905 119909 119910) 119892 (119910) 119889120583120573 (119910) if 119905 gt 0
119892 (119909) if 119905 = 0(77)
where Γ120573 is the Weinstein heat kernel defined by
Γ120573 (119905 119909 119910) = 120591119909 (119864(120573)
119905) (119910) (78)
where
119864(120573)
119905(119910) =
2
1205871198892Γ (120573 + 1) (4119905)
120573+1+1198892119890minus11991024119905 (79)
Thus
119867120573 (119905) 119892 (119909) = 119892lowast119882119864(120573)
119905 (119909) (80)
In practice we use the integral formulation of (76)
119906 (119905 119909) = 119867120573 (119905) 119892 (119909) + 119866120573 (119891) (119905 119909)
= 119867120573 (119905) 119892 (119909) + int
119905
0
119867120573 (119905 minus 119904) 119891 (119904 119909) 119889119904
(81)
Remark 25 The function 119864(120573)119905
is the Gauss kernel associatedwith Weinstein operators This function satisfies
forall120585 isin R119889+1
+ F119882 (119864
(120573)
119905) (120585) = 119890
minus1199051205852
(82)
Proposition 26 Let 1 le 119901 le 119903 le infin and let 119891 isin 119871119901
120573(R119889+1
+)
Then the operator 119867120573(119905) maps 119871119901
120573(R119889+1
+) continuously to
119871119903
120573(R119889+1
+) and
10038171003817100381710038171003817119867120573 (119905) 119891
10038171003817100381710038171003817119871119903120573(R119889)
le 119862119905minus((119889+2120573+2)2)(1119901minus1119903)1003817
1003817100381710038171198911003817100381710038171003817119871119901
120573(R119889)
(83)
Moreover1003817100381710038171003817100381710038171003817
(minusΔ 120573)
1205752
119867120573 (119905) 119891
1003817100381710038171003817100381710038171003817119871119903120573(R119889)
le 119862119905minus1205752minus((119889+2120573+2)2)(1119901minus1119903)1003817
1003817100381710038171198911003817100381710038171003817119871119901
120573(R119889)
(84)
for all 120575 gt 0
Proof It follows from the relations (80) and (29) combinedwith scaling property of the kernel 119864(120573)
119905
In this section we prove estimates for the Weinstein heatsemigroupThese estimates are based on the following result
Lemma 27 Let C be an annulus Positive constants 119888 and 119862exist such that for any 119901 in [1infin] and any couple (119905 120582) ofpositive real numbers one has
suppF119882 (119906) sub 120582C 997904rArr
10038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
le 119862119890minus1198881199051205822
119906119871119901
120573(R119889+1+
)
(85)
8 Journal of Function Spaces and Applications
Proof We again consider a function Θ in 119863(R119889+1
+ 0) the
value of which is identically 1 in neighborhood of annulusCWe can also assume without loss of generality that 120582 = 1 Wethen have
119867120573 (119905) 119906 = 119892 (119905 sdot) lowast119882119906 (86)where
119892 (119905 sdot) = Fminus1
119882(Θ (120585) 119890
minus1199051205852
) (87)
The lemma is proved provided that we can find positive realnumbers 119888 and 119862 such that
forall119905 gt 01003817100381710038171003817119892 (119905 sdot)
10038171003817100381710038171198711120573(R119889+1+
)le 119862119890
minus119888119905 (88)
To begin we perform integrations by parts in (87) We get1003816100381610038161003816119892 (119905 119909)
1003816100381610038161003816=
1
119888120573
(1 + 1199092)
minus(119889+[2120573]+3)
times int
R119889+1+
Λ (119909 120585) (119868119889 minus Δ 120573)
119889+[2120573]+3
times (Θ (120585) 119890minus1199051205852
) 119889120583120573 (120585)
(89)
Using Leibnizrsquos formula we obtain1003816100381610038161003816119892 (119905 119909)
1003816100381610038161003816le 119862(1 + 119909
2)
minus(119889+[2120573]+3)
119890minus119888119905 (90)
and (88) follows
For any interval 119868 of R (bounded or unbounded) wedefine themixed space-time 119871119901(119868 119871119902
120573(R119889+1
+)) Banach space of
(classes of) measurable functions 119906 119868 rarr 119871119902
120573(R119889+1
+) such
that 119906119871119901(119868119871
119902
120573(R119889+1+
))lt infin with
119906119871119901(119868119871119902
120573(R119889+1+
))= (int
119868
119906 (119905 sdot)119901
119871119902
120573(R119889+1+
)119889119905)
1119901
if 1 le 119901 119902 lt infin
119906119871infin(119868119871119902
120573(R119889+1+
))= ess sup
119905isin119868
119906 (119905 sdot)119871119902
120573(R119889+1+
) if 1 le 119902 lt infin
(91)Corollary 28 Let C be an annulus and 120582 a positive realnumber Let 1199060 (resp 119891 = 119891(119905 119909)) satisfy suppF119882(1199060) sub 120582C(resp suppF119882(119891(119905 sdot)) sub 120582C for all 119905 in [0 119879]) Consider 119906 asolution of
120597119905119906 minus Δ 120573119906 = 0 119906|119905=0 = 1199060 (92)and V a solution of
120597119905V minus Δ 120573V = 119891 (119905 sdot) V|119905=0 = 0 (93)There exist positive constants 119888 and 119862 depending only on Csuch that for any 1 le 119886 le 119887 le infin and 1 le 119901 le 119902 le infin we have
119906119871119902([0119879]119871119887120573(R119889+1+
))le 119862120582
(119889+2120573+2)(1119886minus1119887)120582minus21199021003817
1003817100381710038171199060
1003817100381710038171003817119871119886120573(R119889+1+
)
V119871119902([0119879]119871119887120573(R119889+1+
))le 119862120582
minus2(1+1119902minus1119901)120582(119889+2120573+2)(1119886minus1119887)
times10038171003817100381710038171198911003817100381710038171003817119871119901([0119879]119871119886
120573(R119889+1+
))
(94)
Proof It suffices to use the fact that
119906 (119905 sdot) = 119867120573 (119905) 1199060 V (119905 sdot) = int119905
0
119867120573 (119905 minus 119904) 119891 (119904 sdot) 119889119904
(95)
Combining Lemma 27 and Youngrsquos inequality (29) withscaling property of the kernel 119864(120573)
119905now yields the result
Theorem 29 Let 119904 be a positive real number and (119901 119903) isin
[1infin]2 A constant 119862 exists which satisfies the following
property For 119906 isin Bminus2119904120573
119901119903 (R119889+1
+) one has
119862minus1119906
Bminus2119904120573
119901119903(R119889+1+
)le
10038171003817100381710038171003817100381710038171003817
10038171003817100381710038171003817119905119904119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
10038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
le 119862119906Bminus2119904120573
119901119903(R119889+1+
)
(96)
To prove this result we need the following lemma
Lemma 30 There exist two positive constants 120581 and 119862
depending only on 120593 such that for all 1 le 119901 le infin 120591 ge 0 and119895 isin Z one has
10038171003817100381710038171003817Δ 119895 (119867120573 (120591) 119906)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862119890
minus1205812211989512059110038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
) (97)
Proof The result follows immediately by applying Lemma 27and because Δ 119895(119867120573(120591))119906 = (119867120573(120591)Δ 119895)119906
Proof of Theorem 29 Using Lemma 30 and considering thefact that the operator Δ 119895 commutes with the operator 119867120573(119905)
and the definition of the homogeneous Weinstein-Besov(semi) norm we get
10038171003817100381710038171003817119905119904119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862119906
Bminus2119904120573
119901119903(R119889+1+
)sum
119895isinZ
11990511990422119895119904119890minus12058111990522119895
119888119903119895
(98)
where (119888119903119895)119895isinZ denotes as in all this proof a generic elementof the unit sphere of 119897119903(Z) In the case when 119903 = infin therequired inequality comes immediately from the followingeasy result For any positive 119904 we have
sup119905gt0
sum
119895isinZ
11990511990422119895119904119890minus12058111990522119895
lt infin (99)
In the case 119903 lt infin using the Holder inequality with theweight 22119895119904119890minus1205811199052
2119895
(99) and the Fubini theorem we obtain
int
infin
0
11990511990311990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)
119889119905
119905
le 119862119906119903
Bminus2119904120573
119901119903(R119889+1+
)int
infin
0
(sum
119895isinZ
11990511990422119895119904119890minus12058111990522119895
)
119903minus1
times (sum
119895isinZ
11990511990422119895119904119890minus12058111990522119895
119888119903
119903119895)
119889119905
119905
Journal of Function Spaces and Applications 9
le 119862119906119903
Bminus2119904120573
119901119903(R119889+1+
)int
infin
0
(sum
119895isinZ
11990511990422119895119904119890minus12058111990522119895
119888119903
119903119895)
119889119905
119905
le 119862119906119903
Bminus2119904120573
119901119903(R119889+1+
)sum
119895isinZ
119888119903
119903119895int
infin
0
(11990511990422119895119904119890minus12058111990522119895
)
119889119905
119905
le 119862Γ (119904) 119906119903
Bminus2119904120573
119901119903(R119889+1+
)
(100)
In order to prove the other inequality let us observe thatfor any 119904 greater than minus1 we have
Δ 119895119906 =
1
Γ (119904 + 1)
int
infin
0
119905119904(minusΔ 120573)
119904+1
119867120573 (119905) Δ 119895119906 119889119905 (101)
Then Lemma 30 Proposition 9 and the fact that the operatorΔ 119895 commutes with the operator119867120573(119905) lead to the following
10038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862int
infin
0
11990511990422119895(119904+1)
119890minus1205811199052211989510038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889119905
(102)
In the case 119903 = infin we simply write
10038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862(sup
119905gt0
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
times int
infin
0
22119895(119904+1)
119890minus12058111990522119895
119889119905
le 11986222119895119904(sup119905gt0
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
(103)
In the case 119903 lt infin Holderrsquos inequality with the weight 119890minus12058111990522119895
gives
(int
infin
0
119905119904119890minus1205811199052211989510038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889119905)
119903
le 1198622minus2119895(119903minus1)
int
infin
0
119905119903119904119890minus1205811199052211989510038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)119889119905
(104)
Thanks to (99) and Fubinirsquos theorem we infer from (102) that
sum
119895isinZ
2minus211989511990311990410038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)le 119862int
infin
0
11990511990311990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)
119889119905
119905
(105)
The theorem is proved
Second Proof ofTheorem 29We only consider the case 1 le 119903 ltinfinThe case 119903 = infin can be shown similarlyWe first prove that
119862minus1119906
Bminus2119904120573
119901119903(R119889+1+
)le
10038171003817100381710038171003817100381710038171003817
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
10038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
(106)
It is easy to see that
Δ 119895119906 = 120594119895lowast119882119864(120573)
2minus2119895lowast119882119906
(107)
where 120594119895 = Fminus1
119882(120593(2
minus119895120585)119890
2minus21198951205852
) and119864(120573)2minus2119895
is the Gauss kernelassociated with Weinstein operators By relation (29) we get
10038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le
10038171003817100381710038171003817120594119895
100381710038171003817100381710038171198711120573(R119889+1+
)
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
) (108)
As10038171003817100381710038171003817120594119895
100381710038171003817100381710038171198711120573(R119889+1+
)= int
R119889+1+
100381610038161003816100381610038161003816F
minus1
119882(120593 (120585) 119890
1205852
)
100381610038161003816100381610038161003816119889120583120573 (120585) lt infin (109)
we obtain10038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
) (110)
Moreover simple calculations give that
119864(120573)
2minus2119895lowast119882119906 = 119867120573 (2
minus4119895minus 119905
2) (119864
(120573)
1199052lowast119882119906)
(111)
Thus from Proposition 26 it follows that100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
100381710038171003817100381710038171003817119864(120573)
1199052lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1
+ )
(112)
for any 119905 isin [2minus119895minus1 2minus119895] which implies that
sum
119895isinZ
2minus211990411989511990310038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)
le 119862 sum
119895isinZ
int
2minus119895
2minus119895minus1(119905
2119904100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903119889119905
119905
le 119862int
infin
0
(1199052119904100381710038171003817100381710038171003817119864(120573)
1199052lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903119889119905
119905
le 119862int
infin
0
(11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903119889119905
119905
(113)
where we have used the fact that 119864(120573)1199052lowast119882119906 = 119867120573(119905
2)119906
We now prove that10038171003817100381710038171003817100381710038171003817
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
10038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
le 119862119906Bminus2119904120573
119901119903(R119889+1+
) (114)
Indeed one has
119864(120573)
2minus2119895lowast119882119906 = sum
119899isinZ
119864(120573)
2minus2119895lowast119882Δ 119899+119895119906 (115)
Arguing as above we have100381710038171003817100381710038171003817119864(120573)
1199052lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1
+ )
(116)
for any 119905 isin [2minus119895 21minus119895] Thus10038171003817100381710038171003817100381710038171003817
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
10038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
= 2
100381710038171003817100381710038171003817100381710038171003817
1003817100381710038171003817100381710038171199052119904119864(120573)
1199052lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)
100381710038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
le 119862 sum
119895isinZ
int
21minus119895
2minus119895(2
minus2119895119904100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903119889119905
119905
le 119862 sum
119895isinZ
(2minus2119895119904
sum
119899isinZ
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
(117)
10 Journal of Function Spaces and Applications
On the other hand it is easy to see that100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)le 1198622
minus211989911990410038171003817100381710038171003817Δ 119899+119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
) (118)
for any 119904 gt 0 For 0 lt 1199041 lt 119904 lt 1199042 and by using theMinkowskiinequality we have
sum
119895isinZ
(2minus2119895119904
sum
119899isinZ
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
le sum
119895isinZ
(2minus2119895119904
0
sum
minusinfin
2minus21198991199041
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
+ sum
119895isinZ
(2minus2119895119904
sum
119899isinN
2minus21198991199042
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
le 119862(
0
sum
minusinfin
2minus2119899(119904
1minus119904)(sum
119895isinZ
(2minus2(119899+119895)11990311990410038171003817
100381710038171003817Δ 119899+119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
)
1119903
)
119903
+ 119862(sum
N
2minus2119899(119904
2minus119904)(sum
119895isinZ
(2minus2(119899+119895)11990311990410038171003817
100381710038171003817Δ 119899+119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
)
1119903
)
119903
le 119862 sum
119895isinZ
2minus211989511990311990410038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)
(119)
The result is immediately from (117) and (119)
42 Embedding Sobolev Theorems
Theorem 31 Let 1 lt 119901 lt infin and let 0 lt 119904 lt (119889 + 2120573 +
2)119901There exists a positive constant119862 such that for all function119891 isin
H119904
119901120573(R119889+1
+) one has
10038171003817100381710038171198911003817100381710038171003817119871119902
120573(R119889+1+
)le 119862
10038171003817100381710038171198911003817100381710038171003817
1minus120579
H119904119901120573(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
120579
B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
) (120)
where 120579 = 119904119901(119889+2120573+2) and 119902 = 119901(119889+2120573+2)(119889+2120573+2minus119901119904)
Proof Bydensity we can suppose that119891belongs toSlowast(R119889+1
)It is easy to see that
119891 = int
infin
0
119867120573 (119905) Δ 120573119891119889119905(121)
and decompose the integral in two parts as follows
119891 = int
119860
0
119867120573 (119905) Δ 120573119891119889119905 + int
infin
119860
119867120573 (119905) Δ 120573119891119889119905(122)
where 119860 is a constant to be fixed laterOn the other hand byTheorem 29 we obtain10038171003817100381710038171003817119867120573 (119905) Δ 120573119891
10038171003817100381710038171003817119871infin120573(R119889+1+
)
le
119862
1199051minus(12)(119904minus(119889+2120573+2)119901)
10038171003817100381710038171198911003817100381710038171003817B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
)
(123)
Therefore after integrating we get
int
infin
119860
10038171003817100381710038171003817119867120573 (119905) Δ 120573119891
10038171003817100381710038171003817119871infin120573(R119889+1+
)119889119905
le 119860(12)(119904minus(119889+2120573+2)119901)1003817
1003817100381710038171198911003817100381710038171003817B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
)
(124)
On the other hand denoting 119892 = (minusΔ 120573)1199042119891 we have
119867120573 (119905) Δ 120573119891 =
1
(minus119905)1minus1199042
119867120573 (119905) (minus119905Δ 120573)
1minus1199042
119892 (125)
We proceed as in [8] we prove that1003816100381610038161003816100381610038161003816
119867120573 (119905) (minus119905Δ 120573)
1minus1199042
119892 (119909)
1003816100381610038161003816100381610038161003816
le 119862 (119904)119872120573 (119892) (119909) (126)
where119872120573(119892) is a maximal function of 119892 associated with theWeinstein operators (cf [12])
This leads to100381610038161003816100381610038161003816100381610038161003816
int
119860
0
119867120573 (119905) Δ 120573119891 (119909) 119889119905
100381610038161003816100381610038161003816100381610038161003816
le 1198621198601199042119872120573 (119892) (119909) (127)
In conclusion we get10038161003816100381610038161003816100381610038161003816
int
infin
0
119867120573 (119905) Δ 120573119891 (119909) 119889119905
10038161003816100381610038161003816100381610038161003816
le 119862 (1198601199042119872120573 (119892) (119909)
+119860(12)(119904minus(119889+2120573+2)119901)1003817
1003817100381710038171198911003817100381710038171003817B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
))
(128)
and the choice of 119860 such that
119860(119889+2120573+2)2119901
119872120573 (119892) (119909) =10038171003817100381710038171198911003817100381710038171003817B119904minus(119889+2120573+2)119901120573
infininfin (R119889+1+
)(129)
ensures that10038161003816100381610038161003816100381610038161003816
int
infin
0
119867120573 (119905) Δ 120573119891 (119909) 119889119905
10038161003816100381610038161003816100381610038161003816
le 119862(119872120573(119892)(119909))
1minus(119901119904(119889+2120573+2))10038171003817100381710038171198911003817100381710038171003817
119901119904(119889+2120573+2)
B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
)
(130)
Finally taking the 119871119902120573norm with 119902 = 119901(119889 + 2120573 + 2)(119889 + 2120573 +
2minus119901119904) ends the proof thanks to the fact themaximal function119872120573 is bounded of 119871119902
120573(R119889+1
+) into itself for 119902 gt 1
Theorem 32 Let 1 lt 119901 lt 119902 lt infin For all function 119891 such that119891 isin
H1199041
119901120573(R119889+1
+)⋂
Bminus120573120573
infininfin(R119889+1
+) one has
10038171003817100381710038171198911003817100381710038171003817H119904119901120573(R119889+1+
)le 119862
10038171003817100381710038171198911003817100381710038171003817
120579
H1199041
119901120573(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
1minus120579
Bminus120573120573
infininfin(R119889+1
+) (131)
where 120579 = 119901119902 119904 = 1205791199041 minus (1 minus 120579)120573 with 120573 gt 0 minus120573 lt 119904 lt 1199041
Proof It suffices to prove that1003817100381710038171003817100381710038171003817
(minusΔ 120573)
(119904minus1199041)2
119891
1003817100381710038171003817100381710038171003817119871119902
120573(R119889+1+
)
le 11986210038171003817100381710038171198911003817100381710038171003817
120579
119871119901
120573(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
1minus120579
Bminus120573minus1199041120573
infininfin (R119889+1+
)
(132)
Journal of Function Spaces and Applications 11
Indeed we use the following identity (which may be easilyproven by taking the Weinstein transform in 119909 of both sides)
(minusΔ 120573)
minus1205752
119891 (119909) =
1
Γ (1205752)
int
infin
0
1199051205752minus1
119867120573 (119905) 119891 (119909) 119889119905 (133)
with 120575 = 1199041 minus 119904 gt 0We decompose the integral in two parts as follows
(minusΔ 120573)
minus1205752
119891 (119909) =
1
Γ (1205752)
int
119879
0
1199051205752minus1
119867120573 (119905) 119891 (119909) 119889119905
+
1
Γ (1205752)
int
infin
119879
1199051205752minus1
119867120573 (119905) 119891 (119909) 119889119905
(134)
where 119879 is a constant to be fixed laterWe proceed as in [8] we obtain
10038161003816100381610038161003816119867120573 (119905) 119891 (119909)
10038161003816100381610038161003816le 119862119872120573 (119891) (119909) (135)
On the other hand we use Theorem 29 and the fact that 119891belongs to Bminus120573minus119904
1120573
infininfin(R119889+1
+) to deduce that
10038161003816100381610038161003816119867120573 (119905) 119891 (119909)
10038161003816100381610038161003816le 119862119905
(minus120573minus1199041)210038171003817100381710038171198911003817100381710038171003817Bminus120573minus1199041120573
infininfin (R119889+1+
) (136)
Thus by applying the preceding estimates on the right part of(134) we obtain
1003816100381610038161003816100381610038161003816
(minusΔ 120573)
minus1205752
119891 (119909)
1003816100381610038161003816100381610038161003816
le
1198621
Γ (1205752)
1198791205752119872120573 (119891) (119909)
+
1198622
Γ (1205752)
119879(120575minus120573minus119904
1)210038171003817100381710038171198911003817100381710038171003817Bminus120573minus1199041120573
infininfin (R119889+1+
)
(137)
We fix now
119879 = (
10038171003817100381710038171198911003817100381710038171003817Bminus120573minus1199041120573
infininfin (R119889+1+
)
119872120573 (119891) (119909)
)
2(120573+1199041)
(138)
We obtain
1003816100381610038161003816100381610038161003816
(minusΔ120573)
minus1205752
119891 (119909)
1003816100381610038161003816100381610038161003816
le
1198621 + 1198622
Γ (1205752)
(119872120573(119891)(119909))
12057910038171003817100381710038171198911003817100381710038171003817
1minus120579
Bminus120573minus1199041120573
infininfin (R119889+1+
)
(139)
Thus we deduce that1003817100381710038171003817100381710038171003817
(minusΔ120573)
minus1205752
119891
1003817100381710038171003817100381710038171003817119871119902
120573(R119889+1+
)
le
1198621 + 1198622
Γ (1205752)
10038171003817100381710038171003817119872120573 (119891)
10038171003817100381710038171003817
120579
119871119901
120573(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
1minus120579
Bminus120573minus1199041120573
infininfin (R119889+1+
)
(140)
To conclude we used the fact that the maximal function119872120573
is bounded of 119871119902120573(R119889+1
+) into itself for 119902 gt 1
43 Estimates in Generalized Besov Spaces For any interval 119868ofR (bounded or unbounded) and a normed space 119865(R119889+1
+)
we define the mixed space-time 119871119901(119868 119865(R119889+1
+)) space of
(classes of) measurable functions 119906 119868 rarr 119865(R119889+1
+) such that
||119906||119871119901(119868119865(R119889+1+
)) lt infin with
119906119871119901(119868119865(R119889+1+
)) = (int
119868
119906 (119905 sdot)119901
119865(R119889+1+
)119889119905)
1119901
if 1 le 119901 lt infin
119906119871infin(119868119865(R119889+1+
)) = ess sup119905isin119868
119906 (119905 sdot)119865(R119889+1+
)
(141)
For any interval 119868 of R (bounded or unbounded) anda Banach space 119883 we define the mixed space-time 119862(119868119883)space of continuous functions 119868 rarr 119883 When 119868 is bounded119862(119868119883) is a Banach space with the norm of 119871infin(119868 119883)
Theorem 33 Let 119904 isin R and 1 le 119901 119902 119903 le infin Let 119879 gt 0 119892 isin
B119904120573
119901119903(R119889+1
+) and119891 in 119871119902((0 119879) B
119904minus2+(2119902)120573
119901119903 (R119889+1
+)) Then (76)
has a unique solution
119906 isin 119871119902((0 119879)
B119904+(2119902)120573
119901119903(R
119889+1
+))
⋂119871infin((0 119879)
B119904120573
119901119903(R
119889+1
+))
(142)
and there exists a constant 119862 such that for all 1199021 isin [119902infin] onehas
1199061198711199021 ((0119879)B
119904+(21199021)120573
119901119903(R119889+1+
))
le 119862(10038171003817100381710038171198921003817100381710038171003817B119904120573
119901119903(R119889+1+
)+10038171003817100381710038171198911003817100381710038171003817119871119902((0119879)B
119904minus2+(2119902)120573
119901119903(R119889+1+
)))
(143)
If in addition 119903 lt infin then 119906 isin 119862([0 119879] B119904120573
119901119903(R119889+1
+))
Proof Since 119892 and 119891 are temperate distributions (76) has aunique solution 119906 in S1015840
((0 119879) timesR119889+1
+) which satisfies
F119882 (119906) (119905 120585) = 119890minus1199051205852
F119882 (119892) (120585)
+ int
119905
0
119890(120591minus119905)120585
2
F119882 (119891) (120591 120585) 119889120591
(144)
Next we notice that applying Δ 119895 to (76) and using formula(81) yield
Δ 119895119906 (119905 sdot) = 119867120573 (119905) Δ 119895119892 + int
119905
0
119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot) 119889120591(145)
Therefore
10038171003817100381710038171003817Δ 119895119906 (119905 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le
10038171003817100381710038171003817119867120573(119905)Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+ int
119905
0
10038171003817100381710038171003817119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591
(146)
12 Journal of Function Spaces and Applications
By virtue of Lemma 30 we thus have for some 120581 gt 0
10038171003817100381710038171003817Δ 119895119906(119905 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
le 119862[119890minus1205812211989511990510038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+ int
119905
0
119890minus12058122119895(119905minus120591) 10038171003817
100381710038171003817Δ 119895119891 (120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591]
(147)
Applying convolution inequalities we get
10038171003817100381710038171003817Δ 119895119906
100381710038171003817100381710038171198711199021 ((0119879)119871
119901
120573(R119889+1+
))
le 119862[
[
((
1 minus 119890minus120581119879119902122119895
120581119902122119895
)
11199021
)
10038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+((
1 minus 119890minus120581119879119902222119895
120581119902222119895
)
11199022
)
10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119902((0119879)119871
119901
120573(R119889+1+
))
]
]
(148)
with 11199022 = 1+ 11199021 minus1119902 Finally taking the 119897119903(Z) norm we
conclude that (with the usual convention if 119903 = infin)
1199061198711199021 ((0119879)B
119904+(21199021)120573
119901119903(R119889+1+
))
le 119862[
[
sum
119895isinZ
((
1 minus 119890minus120581119879119902122119895
120581119902122119895
)
1199031199021
)(211989511990410038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
]
]
1119903
+ 119862[
[
sum
119895isinZ
((
1 minus 119890minus120581119879119902222119895
120581119902222119895
)
1199031199022
)
times (2119895(119904minus2+2119902)10038171003817
100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119902(0119879119871
119901
120573(R119889+1+
))
119903
]
]
1119903
(149)
which insures that 119906 isin 119871119902((0 119879)
B119904+(2119902)120573
119901119903 (R119889+1
+))
⋂119871infin((0 119879)
B119904120573
119901119903(R119889+1
+)) and yields the desired inequality
Since 119906 belongs to 119862([0 119879]B119904120573
119901119903(R119889+1
+)) in the case where
119903 is finite may be easily deduced from the density ofSlowast(R
119889+1)⋂
B119904120573
119901119903(R119889+1
+) in B
119904120573
119901119903(R)
Theorem 34 Let 119904 isin R 119879 gt 0 and 1 le 119901 119902 119903 le infinOne supposes that 119892 isin 119861
119904120573
119901119903(R119889+1
+) and 119891 isin 119871
119902((0 119879)
119861119904minus2+(2119902)120573
119901119903 (R119889+1
+)) Then (76) has a unique solution 119906 belong-
ing to
119871119902((0 119879) 119861
119904+(2119902)120573
119901119903(R
119889+1
+))⋂119871
infin((0 119879) 119861
119904120573
119901119903(R
119889+1
+))
(150)
and there exists a constant 119862 such that for all 119902 le 1199021 le infin
1199061198711199021 ((0119879)119861
119904+(21199021)120573
119901119903(R119889+1+
))
le 119862 [ (1 + 11987911199021)10038171003817100381710038171198921003817100381710038171003817119861119904120573
119901119903(R119889+1+
)
+ (1 + 1198791+1119902
1minus1119902
)10038171003817100381710038171198911003817100381710038171003817119871119902((0119879)119861
119904minus2+(2119902)120573
119901119903(R119889+1+
))]
(151)
If in addition 119903 lt infin then 119906 isin 119862([0 119879] 119861119904120573119901119903(R119889+1
+))
Proof Since 119892 119891 are tempered (76) has a unique solution 119906in S1015840
((0 119879) timesR119889+1
+) satisfying
F119882 (119906) (119905 120585) = 119890minus1199051205852
F119882 (119892) (120585)
+ int
119905
0
119890(120591minus119905)120585
2
F119882 (119891) (120591 120585) 119889120591
(152)
Hence applying Δ 119895 119895 ge 0 to (81) we see that
Δ 119895119906 (119905 sdot) = 119867120573 (119905) Δ 119895119892 + int
119905
0
119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot) 119889120591(153)
and thus by Lemma 30 we can deduce that10038171003817100381710038171003817Δ 119895119906 (119905 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
le
10038171003817100381710038171003817119867120573(119905)Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)+ int
119905
0
10038171003817100381710038171003817119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591
le 119862[119890minus1205812211989511990510038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+int
119905
0
119890minus12058122119895(119905minus120591)10038171003817
100381710038171003817Δ 119895119891(120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591]
(154)
Then it follows from convolution inequalities thatΔ 1198951199061198711199021 ((0119879)119871
119901
120573(R119889+1+
))is dominated by
(
1 minus 119890minus120581119879119902122119895
120581119902122119895
)
11199021
10038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119861119904120573
119901119903(R119889+1+
)
+ (
1 minus 119890minus120581119879119902222119895
120581119902222119895
)
11199022
10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119902((0119879)119871
119901
120573(R119889+1+
))
(155)
with 11199022 = 1 + 11199021 minus 1119902 Moreover similarly as above wecan obtain that
1003817100381710038171003817Δminus1119906(119905 sdot)
1003817100381710038171003817119871119901
120573(R119889+1+
)le1003817100381710038171003817Δminus1119892
1003817100381710038171003817119871119901
120573(R119889+1+
)
+ int
119905
0
1003817100381710038171003817Δminus1119891 (120591 sdot)
1003817100381710038171003817119871119901
120573(R119889+1+
)119889120591
(156)
and thus if 1 le 119902 le 1199021 le infin1003817100381710038171003817Δminus1119906
10038171003817100381710038171198711199021 ((0119879)119871
119901
120573(R119889+1+
))
le 119862(119879111990211003817100381710038171003817Δminus1119892
1003817100381710038171003817119871119901
120573(R119889+1+
)+ 119879
111990221003817100381710038171003817Δminus1119891
1003817100381710038171003817119871119902((0119879)119871
119901
120573(R119889+1+
)))
(157)
Journal of Function Spaces and Applications 13
Finally taking the 119897119903-normwith respect to 119895 in (155) and (157)with the usual convention if 119903 = infin we can deduce the desiredestimate
Acknowledgment
Theauthor gratefully acknowledges theDeanship of ScientificResearch at the University of Taibah The author is deeplyindebted to the referee for providing constructive commentsand help in improving the contents of this paper
References
[1] Z Ben Nahia and N Ben Salem ldquoSpherical harmonics andapplications associated with the Weinstein operatorrdquo in Pro-ceedings of the International Conference on PotentialTheory heldin Kouty Czech Republic (ICPT rsquo94) pp 235ndash241 1996
[2] Z Ben Nahia and N Ben Salem ldquoOn a mean value propertyassociated with the Weinstein operatorrdquo in Proceedings of theInternational Conference on Potential Theory held in KoutyCzech Republic (ICPT rsquo94) pp 243ndash253 1996
[3] M Brelot ldquoEquation de Weinstein et potentiels de MarcelRieszrdquo in Seminaire de Theorie de Potentiel Paris No 3 vol 681of Lecture Notes in Mathematics pp 18ndash38 Springer BerlinGermany 1978
[4] H Mejjaoli and M Salhi ldquoUncertainty principles for theweinstein transformrdquo Czechoslovak Mathematical Journal vol61 no 4 pp 941ndash974 2011
[5] H Mejjaoli and A Ould Ahmed Salem ldquoWeinstein Gabortransform and applicationsrdquo Advanced Studies in Pure Mathe-matics vol 2 no 3 pp 203ndash210 2012
[6] H Mejjaoli ldquoBesov spaces associated withthe Weinstein opera-tor and applicationsrdquo In press
[7] T Kawazoe and H Mejjaoli ldquoGeneralized Besov spaces andtheir applicationsrdquo Tokyo Journal of Mathematics vol 35 no 2pp 297ndash320 2012
[8] H Mejjaoli ldquoLittlewood-Paley decomposition associated withthe Dunkl operators and paraproduct operatorsrdquo Journal ofInequalities in Pure and Applied Mathematics vol 9 no 4 pp1ndash25 2008
[9] H Mejjaoli and N Sraeib ldquoGeneralized sobolev spaces inquantum calculus and applicationsrdquo Journal of Inequalities andSpecial Functions vol 1 no 4 pp 43ndash64 2012
[10] H Mejjaoli ldquoGeneralized homogeneous Besov spaces and theirapplicationsrdquo Serdica Mathematical Journal vol 38 no 4 pp575ndash614 2012
[11] H Triebel Interpolation Theory Functions Spaces DifferentialOperators North-Holland AmsterdamThe Netherlands 1978
[12] V S Guliev ldquoOn maximal function and fractional integralassociated with the Bessel differential operatorrdquo MathematicalInequalities and Applications vol 6 no 2 pp 317ndash330 2003
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Stochastic AnalysisInternational Journal of
2 Journal of Function Spaces and Applications
we introduce and study the homogeneous Weinstein-Besovspaces the homogeneous Weinstein-Triebel-Lizorkin spacesand the homogeneous Weinstein-Riesz potential spaces InSection 4 we characterize the homogeneousWeinstein Besovspaces via the Weinstein heat semigroup Next we prove theSobolev embedding theorems
2 Preliminaries
In order to confirm the basic and standard notations webriefly overview the Weinstein operator and the relatedharmonic analysis Main references are [1 2]
21 Harmonic Analysis Associated with the Weinstein Opera-tor In this subsection we collect some notations and resultson theWeinstein kernel theWeinstein intertwining operatorand its dual the Weinstein transform and the Weinsteinconvolution
In the following
R119889+1
+= R
119889times [0infin[
119909 = (1199091 119909119889 119909119889+1) = (1199091015840 119909119889+1) isin R
119889+1
+
119909 = radic1199092
1+ sdot sdot sdot + 119909
2
119889+1
(5)
We denote by 119862lowast(R119889+1
) the space of continuous functionson R119889+1 even with respect to the last variable 119862119901
lowast(R119889+1
) thespace of functions of class 119862119901 on R119889+1 even with respectto the last variable Elowast(R
119889+1) the space of 119862infin-functions on
R119889+1 even with respect to the last variable Slowast(R119889+1
) theSchwartz space of rapidly decreasing functions onR119889+1 evenwith respect to the last variable 119863lowast(R
119889+1) the space of 119862infin-
functions on R119889+1 which are of compact support even withrespect to the last variable S1015840
lowast(R119889+1
) the space of temperatedistributions on R119889+1 even with respect to the last variableIt is the topological dual of Slowast(R
119889+1)
We consider the Weinstein operator Δ 120573 defined by
forall119909 = (1199091015840 119909119889+1) isin R
119889times ]0infin[
Δ 120573119891 (119909) = Δ 1199091015840119891 (1199091015840 119909119889+1) +L120573119909
119889+1
119891 (1199091015840 119909119889+1)
119891 isin 1198622
lowast(R
119889+1)
(6)
where Δ 1199091015840 is the Laplace operator on R119889 and L120573119909119889+1
is theBessel operator on ]0infin[ given by
L120573119909119889+1
=
1198892
1198891199092
119889+1
+
2120573 + 1
119909119889+1
119889
119889119909119889+1
120573 gt minus
1
2
(7)
TheWeinstein kernel Λ is given by
Λ (119909 119911) = 119890119894⟨11990910158401199111015840⟩119895120573 (119909119889+1119911119889+1)
forall (119909 119911) isin R119889+1
times C119889+1
(8)
where 119895120573(119909119889+1119911119889+1) is the normalized Bessel function TheWeinstein kernel satisfies the following properties
(i) For each 119911 isin R119889+1
+ we have
Δ 120573Λ (119909 119911) = minus1199112Λ (119909 119911) forall119909 isin R
119889+1
+ (9)
(ii) For all 119911 119905 isin C119889+1 we have
Λ (119911 119905) = Λ (119905 119911) Λ (119911 0) = 1
Λ (120582119911 119905) = Λ (119911 120582119905) forall120582 isin C(10)
(iii) For all ] isin N119889+1 119909 isin R119889+1 and 119911 isin C119889+1 we have1003816100381610038161003816119863
]119911Λ (119909 119911)
1003816100381610038161003816le 119909
|]| exp (119909 Im 119911) (11)
where 119863]119911= 120597
](120597119911
]1
1sdot sdot sdot 120597119911
]119889+1
119889+1) and |]| = ]1 + sdot sdot sdot + ]119889+1 In
particular1003816100381610038161003816Λ (119909 119910)
1003816100381610038161003816le 1 forall119909 119910 isin R
119889+1 (12)
The Weinstein intertwining operator is the operator R120573
defined on 119862lowast(R119889+1
) by
R120573119891 (1199091015840 119909119889+1)
=
2Γ (120573 + 1)
radic120587Γ (120573 + 12)
119909minus2120573
119889+1
timesint
119909119889+1
0
(1199092
119889+1minus 119905
2)
120573minus12
119891 (1199091015840 119905) 119889119905 119909119889+1 gt 0
119891 (1199091015840 0) 119909119889+1 = 0
(13)
R120573 is a topological isomorphism from Elowast(R119889+1
) ontoitself satisfying the following transmutation relation
Δ 120573 (R120573119891) = R120573 (Δ 119889+1119891) forall119891 isin Elowast (R119889+1
) (14)
where Δ 119889+1 = sum119889+1
119895=11205972
119895is the Laplacian on R119889+1
We denote by119871119901120573(R119889+1
+) the space ofmeasurable functions
on R119889+1
+such that
10038171003817100381710038171198911003817100381710038171003817119871119901
120573(R119889+1+
)= (int
R119889+1+
1003816100381610038161003816119891 (119909)
1003816100381610038161003816
119901119889120583120573 (119909))
1119901
lt infin
if 1 le 119901 lt infin
10038171003817100381710038171198911003817100381710038171003817119871infin120573(R119889+1+
)= ess sup
119909isinR119889+1+
1003816100381610038161003816119891 (119909)
1003816100381610038161003816lt infin
(15)
where 119889120583120573 is the measure on R119889+1
+given by
119889120583120573 (1199091015840 119909119889+1) = 119909
2120573+1
119889+1119889119909
1015840119889119909119889+1
(16)
TheWeinstein transform is given for 119891 in 1198711120573(R119889+1
+) by
F119882 (119891) (119910) = int
R119889+1+
119891 (119909)Λ (minus119909 119910) 119889120583120573 (119909) forall119910 isin R119889+1
+
(17)
Some basic properties of this transform are as follows
Journal of Function Spaces and Applications 3
(i) For 119891 in 1198711120573(R119889+1
+)
1003817100381710038171003817F119882 (119891)
1003817100381710038171003817119871infin120573(R119889+1+
)le100381710038171003817100381711989110038171003817100381710038171198711120573(R119889+1+
) (18)
(ii) For 119891 in Slowast(R119889+1
) we have
F119882 (Δ 120573119891) (119910) = minus10038171003817100381710038171199101003817100381710038171003817
2F119882 (119891) (119910) forall119910 isin R
119889+1
+ (19)
(iii) For all 119891 in 1198711120573(R119889+1
+) ifF119882(119891) belongs to 119871
1
120573(R119889+1
+)
then
119891 (119910) = 119862 (120573)int
R119889+1+
F119882 (119891) (119909) Λ (119909 119910) 119889120583120573 (119909) ae
(20)
where
119862 (120573) =
1
1205871198894120573+1198892
(Γ (120573 + 1))2 (21)
(iv) For 119891 isin Slowast(R119889+1
) if we define
F119882 (119891) (119910) = F119882 (119891) (minus119910) (22)
then
(F119882)minus1=
1
119862 (120573)
F119882 (23)
Proposition 1 (see [2]) (i) the Weinstein transform F119882 is atopological isomorphism fromSlowast(R
119889+1) onto itself and for all
f in Slowast(R119889+1
)
int
R119889+1+
1003816100381610038161003816119891 (119909)
1003816100381610038161003816
2119889120583120573 (119909) = 119862 (120573)int
R119889+1+
1003816100381610038161003816F119882 (119891) (120585)
1003816100381610038161003816
2119889120583120573 (120585)
(24)
(ii) In particular the renormalized Weinstein transform119891 rarr 119862(120573)
12F119882(119891) can be uniquely extended to an isometric
isomorphism from 1198712
120573(R119889+1
+) onto itself
In the Fourier analysis the translation operator is givenby 119891 997891rarr 119891(sdot + 119909)
In harmonic analysis associated for the operator Δ 120573 thegeneralized translation operator 120591119909 119909 isin R119889+1
+is defined by
forall119910 isin R119889+1
+
120591119909119891 (119910) =
Γ (120573 + 1)
radic120587Γ (120573 + 12)
times int
120587
0
119891(1199091015840+ 119910
1015840 radic119909
2
119889+1+ 119910
2
119889+1+ 2119909119889+1119910119889+1 cos 120579)
times (sin 120579)2120573119889120579(25)
where 119891 isin 119862lowast(R119889+1
)
By using the Weinstein kernel we can also define ageneralized translation For functions 119891 isin Slowast(R
119889+1) and
119910 isin R119889+1
+the generalized translation 120591119910119891 is defined by the
following relation
F119882 (120591119910119891) (119909) = Λ (119909 119910)F119882 (119891) (119909) (26)
By using the generalized translation we define the general-ized convolution product119891lowast
119882119892 of functions119891 119892 isin 1198711
120573(R119889+1
+)
as follows
119891lowast119882119892 (119909) = int
R119889+1+
120591119909119891 (minus1199101015840 119910119889+1) 119892 (119910) 119889120583120573 (119910) (27)
This convolution is commutative and associative and itsatisfies the following
(i) For all 119891 119892 isin 1198711
120573(R119889+1
+) 119891lowast119882 119892 belongs to 1198711
120573(R119889+1
+)
and
F119882 (119891lowast119882119892) = F119882 (119891)F119882 (119892) (28)
(ii) Let 1 le 119901 119902 119903 le infin such that 1119901 + 1119902 minus 1119903 = 1If 119891 isin 119871
119901
120573(R119889+1
+) and 119892 isin 119871
119902
120573(R119889+1
+) then 119891lowast119882119892 isin
119871119903
120573(R119889+1
+) and
1003817100381710038171003817119891lowast119882119892
1003817100381710038171003817119871119903120573(R119889+1+
)le10038171003817100381710038171198911003817100381710038171003817119871119901
120573(R119889+1+
)
10038171003817100381710038171198921003817100381710038171003817119871119902
120573(R119889+1+
) (29)
We define the tempered distribution T119891 associated with119891 isin 119871
119901
120573(R119889+1
+) by
⟨T119891 120601⟩ = int
R119889+1+
119891 (119909) 120601 (119909) 119889120583120573 (119909) (30)
for 120601 isin Slowast(R119889+1
) and denote by ⟨119891 120601⟩120573 the integral in therighthand side
Definition 2 The Weinstein transform F119882(120591) of a distribu-tion 120591 isin S1015840
lowast(R119889+1
) is defined by
⟨F119882 (120591) 120601⟩ = ⟨120591F119882 (120601)⟩ (31)
for 120601 isin Slowast(R119889+1
)
In particular for 119891 isin 119871119901
120573(R119889+1
+) it follows that for 120601 isin
Slowast(R119889+1
)
⟨F119882 (119891) 120601⟩ = ⟨F119882 (T119891) 120601⟩ = ⟨T119891F119882 (120601)⟩
= ⟨119891F119882 (120601)⟩120573
(32)
Proposition 3 The Weinstein transform F119882 is a topologicalisomorphism from S1015840
lowast(R119889+1
) onto itself
Definition 4 The generalized convolution product of a dis-tribution 119878 in S1015840
lowast(R119889+1
) and a function 120601 in Slowast(R119889+1
) is thefunction 119878lowast119882120601 defined by
119878lowast119882 120601 (119909) = ⟨119878119910 120591minus119910120601 (119909)⟩ (33)
4 Journal of Function Spaces and Applications
Proposition 5 Let 119891 be in 119871119901
120573(R119889+1
+) 1 le 119901 le infin and 120601
in Slowast(R119889+1
) Then the distribution T119891lowast119882120601 is given by thefunction 119891lowast119882120601 and T119891lowast119882120601 belongs to 119871119901
120573(R119889+1
+) Moreover
for all 120595 isin Slowast(R119889+1
)
⟨T119891lowast119882120601 120595⟩ = ⟨
119891 120601lowast119882 ⟩120573 (34)
where (119909) = 120595(minus119909) and
F119882 (T119891lowast119882 120601) = F119882 (T119891)F119882 (120601) (35)
For each 119906 isin S1015840
lowast(R119889+1
) we define the distribution Δ 120573119906
by ⟨Δ 120573119906 120595⟩ = ⟨119906 Δ 120573120595⟩ and this distribution satisfies thefollowing property
F119882 (Δ 120573119906) = minus10038171003817100381710038171199101003817100381710038171003817
2F119882 (119906) (36)
In the following we denote T119891 given by (30) by 119891 forsimplicity
3 B119904120573
119901119902 F119904120573
119901119902(R119889+1
+) H119904
119901120573Spaces and
Basic Properties
31 HomogeneousWeinstein-Littlewood-Paley DecompositionOne of the main tools in this paper is the homogeneousLittlewood-Paley decomposition of distribution associatedwith theWeinstein operators into dyadic blocs of frequencies
Lemma6 One defines byC the ring of center 0 of small radius12 and great radius 2 There exists two radial functions 120595 and120593 the values of which are in the interval [0 1] belonging to119863lowast(R
119889+1) such that
supp120595 sub 119861 (0 1) supp120593 sub C
forall120585 isin R119889+1
120595 (120585) + sum
119895ge0
120593 (2minus119895120585) = 1
forall120585 isin C sum
119895isinZ
120593 (2minus119895120585) = 1
|119899 minus 119898| ge 2 997904rArr supp120593 (2minus119899sdot) cap supp120593 (2minus119898sdot) = 0
119895 ge 1 997904rArr supp120595 cap supp120593 (2minus119895sdot) = 0
(37)
Notations We denote by
Δ 119895119891 = Fminus1
119882(120593(
120585
2119895)F119882 (119891))
119878119895119891 = sum
119899le119895minus1
Δ 119899119891 forall119895 isin Z(38)
The distribution Δ 119895119891 is called the 119895th dyadic block of thehomogeneous Littlewood-Paley decomposition of 119891 associ-ated with the Weinstein operators
Throughout this paper we define 120601 and 120594 by 120601 = Fminus1
119882(120593)
and 120594 = Fminus1
119882(120595)
When dealing with the Littlewood-Paley decompositionit is convenient to introduce the functions and 120593 belongingto119863lowast(R
119889+1) such that equiv 1 on supp120595 and 120593 equiv 1 on supp120593
Remark 7 We remark that
F119882 (119878119895119891) (120585) = (
120585
2119895)F119882 (119878119895119891) (120585)
F119882 (Δ 119895119891) (120585) = 120593(
120585
2119895)F119882 (Δ 119895119891) (120585)
(39)
We put
120601 = F
minus1
119882(120593) 120594 = F
minus1
119882() (40)
Definition 8 One denotes by S1015840
ℎ120573lowast(R119889+1
) the space oftempered distribution such that
lim119895rarrminusinfin
119878119895119906 = 0 in S1015840
lowast(R
119889+1) (41)
Proposition 9 (Bernstein inequalities) For all 120583 isin N119889+1 and120590 isin R for all 119895 isin Z for all 1 le 119901 119902 le infin and for all119891 isin S1015840
lowast(R119889+1
) one has the following
(i) 10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119902
120573(R119889+1+
)
le
10038171003817100381710038171003817
120601
10038171003817100381710038171003817119871119903120573(R119889+1+
)
10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119901
120573(R119889+1+
)2119895(119889+2120573+2)(1119901minus1119902)
with 1
119902
=
1
119901
+
1
119903
minus 1
(ii) 10038171003817100381710038171003817119878119895119891
10038171003817100381710038171003817119871119902
120573(R119889+1+
)
le10038171003817100381710038171205941003817100381710038171003817119871119903120573(R119889+1+
)
10038171003817100381710038171003817119878119895119891
10038171003817100381710038171003817119871119901
120573(R119889+1+
)2119895(119889+2120573+2)(1119901minus1119902)
with 1
119902
=
1
119901
+
1
119903
minus 1
(iii)1003817100381710038171003817100381710038171003817
(radicminusΔ 120573)
120590
Δ 119895119891
1003817100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)
le
10038171003817100381710038171003817F
minus1
119882(10038171003817100381710038171205851003817100381710038171003817
120590120593)
100381710038171003817100381710038171198711120573(R119889+1+
)
times
10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119901
120573(R119889+1+
)2119895120590
(42)
Proof Using Remark 7 we deduce from Proposition 5 that
119878119895119891 = 2119895(119889+2120573+2)
120594 (2119895sdot) lowast119882119878119895119891
Δ 119895119891 = 2119895(119889+2120573+2)
120601 (2119895sdot) lowast119882Δ 119895119891
(43)
Thus from the relation (29) we prove (i) (ii) and (iii)
32 Definitions In the following we define analogues of thehomogeneous Besov Triebel-Lizorkin and Riesz potentialspaces associated with the Weinstein operators on R119889+1
+and
obtain their basic propertiesFrom now we make the convention that for all non-
negative sequence 119886119902119902isinZ the notation (sum119902119886119903
119902)1119903 stands for
sup119902119886119902 in the case 119903 = infin
Journal of Function Spaces and Applications 5
Definition 10 Let 119904 isin R and 119901 119902 isin [1infin]The homogeneousWeinstein-Besov spaces B
119904120573
119901119902(R119889+1
+) are the spaces of distri-
bution in S1015840
ℎ120573lowast(R119889+1
) such that
10038171003817100381710038171198911003817100381710038171003817B119904120573
119901119902(R119889+1+
)= (sum
119895isinZ
(211990411989510038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119902
)
1119902
lt infin (44)
Proposition 11 (see [6]) Let 119904 isin R and 119901 and 119902 two elementsof [1infin] the space B
119904120573
119901119902(R119889+1
+) is the set of 119891 isin S1015840
ℎ120573lowast(R119889+1
)
verifying
10038171003817100381710038171003817
119891
10038171003817100381710038171003817B119904120573
119901119902(R119889+1+
)= (int
infin
0
(119905minus1199041003817100381710038171003817119891lowast119882120601119905
1003817100381710038171003817119871119901
120573(R119889+1+
))
119902119889119905
119905
)
1119902
lt infin
(45)
where 120601119905(119909) = (11199052120573+2+119889
)120601(119909119905) for all 119905 isin (0infin) and 119909 isin
R119889+1
+
Definition 12 For 119904 isin R and 119901 119902 isin [1infin] one writes10038171003817100381710038171198911003817100381710038171003817119861119904120573
119901119902(R119889+1+
)=10038171003817100381710038171198780119891
1003817100381710038171003817119871119901
120573(R119889+1+
)
+ (sum
119895ge1
(211990411989510038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119902
)
1119902
(46)
The nonhomogeneous Besov space 119861119904120573119901119902(R119889+1
+) associated
with the Weinstein operators is defined by
119861119904120573
119901119902(R
119889+1
+) = 119891 isin S
1015840(R
119889)
10038171003817100381710038171198911003817100381710038171003817119861119904120573
119901119902(R119889+1+
)lt infin (47)
We give now another definition equivalent to the nonho-mogeneous Besov space 119861119904120573119901119902(R119889+1
+)
Proposition 13 Let 119904 isin R and119901 and 119902 two elements of [1infin]the space 119861119904120573119901119902(R119889+1
+) is the set of 119891 isin S1015840
(R119889) verifying
10038171003817100381710038171003817
119891
10038171003817100381710038171003817119861119904120573
119901119902(R119889+1+
)=1003817100381710038171003817119891lowast119882120595
1003817100381710038171003817119871119901
120573(R119889+1+
)
+ (int
1
0
(119905minus1199041003817100381710038171003817119891lowast119882120601119905
1003817100381710038171003817119871119901
120573(R119889+1+
))
119902119889119905
119905
)
1119902
lt infin
(48)
Definition 14 Let 119904 isin R and 1 le 119901 119902 le infin the homogeneousWeinstein-Triebel-Lizorkin space F
119904120573
119901119902(R119889+1
+) is the space of
distribution in S1015840
ℎ120573lowast(R119889+1
) such that
10038171003817100381710038171198911003817100381710038171003817F119904120573
119901119902(R119889+1+
)=
100381710038171003817100381710038171003817100381710038171003817100381710038171003817
(sum
119895isinZ
211990411989511990210038161003816100381610038161003816Δ 119895119891
10038161003816100381610038161003816
119902
)
1119902100381710038171003817100381710038171003817100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)
lt infin (49)
Definition 15 For 119904 isin R the operatorR119904
120573from S1015840
ℎ120573lowast(R119889+1
)
to S1015840
ℎ120573lowast(R119889+1
) is defined by
R119904
120573(119891) = F
minus1
119882(sdot
119904F119882119891) (50)
The operatorRminus119904
120573is called Weinstein-Riesz potential space
Definition 16 For 119904 isin R and 1 le 119901 le infin the homogeneousWeinstein-Riesz potential space H119904
119901120573(R119889+1
+) is defined
as the space Rminus119904
120573(119871
119901
120573(R119889+1
+)) equipped with the norm
119891H119904119901120573(R119889+1+
)= R119904
120573(119891)
119871119901
120573(R119889+1+
)
Proposition 17 Let 119904 isin R and 1 le 119901 119902 le infinThe operator Δ 120573 is a linear continuous operator from
B119904120573
119901119902(R119889+1
+) into B
119904minus2120573
119901119902 (R119889+1
+) and from H119904
119901120573(R119889+1
+) into
H119904minus2
119901120573(R119889+1
+)
Proof We obtain these results by the similar ideas used in thenonhomogeneous case (cf [6])
Proposition 18 Let 119904 119905 isin R and 1 le 119901 119902 le infin The operatorR119905
120573is a linear continuous injective operator from B
119904120573
119901119902(R119889+1
+)
onto B119904minus119905120573
119901119902 (R119889+1
+) and from H119904
119901120573(R119889+1
+) onto H119904minus119905
119901120573(R119889+1
+)
Proof We obtain these results by the similar ideas used in thenonhomogeneous case (cf [6])
33 Embeddings As in the Euclidean case (cf [11]) themono-tone character of 119897119902-spaces and the Minkowskis inequalityyield the following
Proposition 19 If 1 le 1199021 lt 1199022 le infin one has
B119904120573
1199011199021
(R119889+1
+) 997893rarr
B119904120573
1199011199022
(R119889+1
+) (1 le 119901 le infin 119904 isin R)
(51)
MoreoverB119904120573
1199011(R
119889+1
+) 997893rarr
H119904
119901120573(R
119889+1
+) 997893rarr
B119904120573
119901infin(R
119889+1
+)
(1 le 119901 le infin 119904 isin R)
(52)
If 1199040 = 1199041 one also has
(H1199040
119901120573(R
119889+1
+)
H1199041
119901120573(R
119889+1
+))
120579119902=
B119904120573
119901119902(R
119889+1
+)
(1 le 119901 119902 le infin 120579 isin (0 1))
(53)
where 119904 = (1 minus 120579)1199040 + 1205791199041
Proposition 20 One assumes that 119904 minus (119889 + 2120573 + 2)119901 = 1199041 minus
(119889 + 2120573 + 2)1199011 Then the following inclusion holds
B119904120573
119901119902(R
119889+1
+) 997893rarr
B1199041120573
11990111199021
(R119889+1
+)
(1 le 119901 le 1199011 le infin 1 le 119902 le 1199021 le infin 119904 1199041 isin R)
(54)
Proof In order to prove the inclusion we use the estimate
Δ 119895119891 = 2119895(119889+2120573+2)
120601 (2119895sdot) lowast119882Δ 119895119891 (55)
Proposition 9(i) gives that10038171003817100381710038171003817Δ 119895119891
100381710038171003817100381710038171198711199011
120573(R119889+1+
)=
100381710038171003817100381710038172119895(119889+2120573+2)
120601 (2119895sdot) lowast119882Δ 119895119891
100381710038171003817100381710038171198711199011
120573(R119889+1+
)
le 1198622119895(119889+2120573+2)(1119901minus1119901
1)10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
(56)
6 Journal of Function Spaces and Applications
By definition of the homogeneous Weinstein-Besov spaceswe therefore infer10038171003817100381710038171198911003817100381710038171003817B1199041120573
11990111199021(R119889+1+
)
= (
infin
sum
119895=minusinfin
(2119895119904110038171003817100381710038171003817Δ 119895119891
100381710038171003817100381710038171198711199011
120573(R119889+1+
))
1199021
)
11199021
le 119862(sum
119895isinZ
(211989511990412119895(119889+2120573+2)(1119901minus1119901
1)10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
1199021
)
11199021
le 119862(sum
119895isinZ
(211989511990410038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
1199021
)
11199021
le 11986210038171003817100381710038171198911003817100381710038171003817B119904120573
119901119902(R119889+1+
)
(57)
since 119902 le 1199021 This gives the inclusion
Proposition 21 (1) If 119906 belongs to B119904120573
119901119902(R119889+1
+) cap
B119905120573
119901119902(R119889+1
+)
then 119906 belongs to B120579119904+(1minus120579)119905120573
119901119902 (R119889+1
+) for all 120579 isin [0 1] and
119906B120579119904+(1minus120579)119905120573
119901119902(R119889+1+
)le 119906
120579
B119904120573
119901119902(R119889+1+
)119906
1minus120579
B119905120573
119901119902(R119889+1+
) (58)
(2) If 119906 belongs to B119904120573
119901infin(R119889+1
+) cap
B119905120573
119901infin(R119889+1
+) and 119904 lt 119905
then 119906 belongs to B120579119904+(1minus120579)119905120573
1199011(R119889+1
+) for all 120579 isin (0 1) and there
exists a positive constant 119862(119905 119904) such that
119906B120579119904+(1minus120579)119905120573
1199011(R119889+1+
)le 119862 (119905 119904) 119906
120579
B119904120573
119901infin(R119889+1+
)119906
1minus120579
B119905120573
119901infin(R119889+1+
) (59)
(3) If 119906 belongs to B119904120573
119901infin(R119889+1
+) cap
B119904+120576120573
119901infin (R119889+1
+) and 120576 gt
0 then 119906 belongs to B119904120573
1199011(R119889+1
+) and there exists a positive
constant 119862 such that
119906B119904120573
1199011(R119889+1+
)le
119862
120576
119906B119904120573
119901infin(R119889+1+
)log
2(119890 +
119906B119904+120576120573
119901infin(R119889+1+
)
119906B119904120573
119901infin(R119889+1+
)
)
(60)
Proof (1) is obvious from the Holderrsquos inequality As for (2)we write 119906
B120579119904+(1minus120579)119905120573
1199011(R119889+1+
)as
sum
119895le119873
2119895(120579119904+(1minus120579)119905)10038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)+ sum
119895gt119873
2119895(120579119904+(1minus120579)119905)10038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
(61)
where 119873 is chosen here after By the definition of thehomogeneous Weinstein-Besov norms we see that
2119895(120579119904+(1minus120579)119905)10038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 2
119895(1minus120579)(119905minus119904)119906
B119904120573
119901infin(R119889+1+
)
2119895(120579119904+(1minus120579)119905)10038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 2
minus119895120579(119905minus119904)119906
B119905120573
119901infin(R119889+1+
)
(62)
and thus 119906B120579119904+(1minus120579)119905120573
1199011(R119889+1+
)is dominated by
119906B119904120573
119901infin(R119889+1+
)sum
119895le119873
2119895(1minus120579)(119905minus119904)
+ 119906B119905120573
119901infin(R119889+1+
)sum
119895gt119873
2minus119895120579(119905minus119904)
le 119862119906B119904120573
119901infin(R119889+1+
)
2(119873+1)(1minus120579)(119905minus119904)
2(1minus120579)(119905minus119904)
minus 1
+ 119906B119905120573
119901infin(R119889+1+
)
2minus119873120579(119905minus119904)
1 minus 2minus120579(119905minus119904)
(63)
Hence in order to complete the proof of (2) it suffices tochoose119873 such that
119906B119905120573
119901infin(R119889)
119906B119904120573
119901infin(R119889)
le 2119873(119905minus119904)
lt 2
119906B119905120573
119901infin(R119889)
119906B119904120573
119901infin(R119889)
(64)
As for (3) it is easy to see that 119906B119904120573
1199011(R119889+1+
)is dominated as
sum
119895le119873minus1
211989511990410038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)+ sum
119895ge119873
211989511990410038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
le (119873 + 1) 119906B119904120573
119901infin(R119889+1+
)+
2minus(119873minus1)120576
2120576minus 1
119906B119904+120576120573
119901infin(R119889+1+
)
(65)
Hence letting
119873 = 1 + [
[
1
120576
log2
119906B119904+120576120573
119901infin(R119889+1+
)
119906B119904120573
119901infin(R119889+1+
)
]
]
(66)
we can obtain the desired estimate
Proposition 22 Let 119902 isin (1infin) and let 119904 isin R such that0 lt 119904 lt (119889 + 2120573 + 2)119902 then one has
B119904120573
119902119902(R
119889+1
+) =
F119904120573
119902119902(R
119889+1
+) 997893rarr
F119904120573
119902infin(R
119889+1
+)
997893rarrF119904minus((119889+2120573+2)119902)120573
infininfin(R
119889+1
+)
(67)
H119904
119902120573(R
119889+1
+) =
F119904120573
1199022(R
119889+1
+) 997893rarr
F119904120573
119902infin(R
119889+1
+)
997893rarrF119904minus((119889+2120573+2)119902)120573
infininfin(R
119889+1
+)
(68)
Proof We obtain these results by the similar ideas used in thenonhomogeneous case (cf [6])
Theorem 23 Let 119886 119887 gt 0 and let 1199021 1199022 isin [1infin] Let120579 = 119886(119886 + 119887) isin (0 1) and let 1119901 = (1 minus 120579)1199021 +
1205791199022 Then there exists a constant 119862 such that for every119891 isin
F119886120573
1199021infin(R119889+1
+) cap
Fminus119887120573
1199022infin(R119889+1
+) then one has
1003816100381610038161003816119891 (119909)
1003816100381610038161003816le 119862(sup
119895isinZ
2119886119895 10038161003816100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
1minus120579
(sup119895isinZ
2minus119887119895 10038161003816
100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
120579
(69)
In particular one gets
10038171003817100381710038171198911003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
10038171003817100381710038171198911003817100381710038171003817
1minus120579
F119886120573
1199021infin(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
120579
Fminus119887120573
1199022infin(R119889+1+
) (70)
Journal of Function Spaces and Applications 7
Proof Let 119891 be a Schwartz class we have
1003816100381610038161003816119891 (119909)
1003816100381610038161003816le sum
119895isinZ
10038161003816100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816
le sum
119895isinZ
min(2minus119886119895sup119895isinZ
(2119886119895 10038161003816100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
2119895119887sup119895isinZ
(2minus119895119887 10038161003816
100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816))
(71)
We define119873(119909) as the largest index such that
2119895119887sup119895isinZ
(2minus119895119887 10038161003816
100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816) le 2
minus119886119895sup119895isinZ
(2119886119895 10038161003816100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816) (72)
and we write1003816100381610038161003816119891 (119909)
1003816100381610038161003816le sum
119895le119873(119909)
2119895119887sup119895isinZ
(2minus119895119887 10038161003816
100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
+ sum
119895gt119873(119909)
2minus119886119895sup
119895
(2119886119895 10038161003816100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
le 119862(sup119895isinZ
2119886119895 10038161003816100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
119887(119886+119887)
times (sup119895isinZ
2minus119887119895 10038161003816
100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
119886(119886+119887)
(73)
Thus (69) is proved In order to obtain (70) it is enough toapply the Holder inequality in the expression above since wehave 120579 = 119886(119886+119887) isin (0 1) and let 1119901 = (1minus120579)1199021+1205791199022
Corollary 24 Let 119902 isin (1infin) and let 119904 isin R such that 0 lt 119904 lt
(119889 + 2120573 + 2)119902 then one has
10038171003817100381710038171198911003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
10038171003817100381710038171198911003817100381710038171003817
1minus(119902119901)
Bminus((2120573+2+119889)119902minus119904)120573
infininfin (R119889+1
+ )
10038171003817100381710038171198911003817100381710038171003817
119902119901
B119904120573
119902119902(R119889+1
+ )
(74)
10038171003817100381710038171198911003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
10038171003817100381710038171198911003817100381710038171003817
1minus(119902119901)
Bminus((2120573+2+119889)119902minus119904)120573
infininfin (R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
119902119901
H119904119902120573(R119889+1+
) (75)
where 119901 = 119902(2120573 + 2 + 119889)(2120573 + 2 + 119889 minus 119902119904)
Proof By choosing 119886 = 119904 gt 0 minus119887 = 119904 minus (119889 + 2120573 + 2)119902 lt 01199021 = 119902 and 1199022 = infin we deduce (74) from the relations (70)and (67) In the same way we deduce (75) from the relations(70) and (68)
4 Generalized Heat Equation
41 Characterization for the Weinstein-Besov Spaces TheWeinstein heat equation reads
120597119905119906 (119905 119909) minus Δ 120573119906 (119905 119909) = 119891 (119905 119909) (119905 119909) isin [0infin) timesR119889+1
+
119906|119905=0 = 119892
(76)
We introduce the Weinstein heat semigroup 119867120573(119905) for theWeinstein-Laplace operator
119867120573 (119905) 119892 (119909) =
int
R119889+1+
Γ120573 (119905 119909 119910) 119892 (119910) 119889120583120573 (119910) if 119905 gt 0
119892 (119909) if 119905 = 0(77)
where Γ120573 is the Weinstein heat kernel defined by
Γ120573 (119905 119909 119910) = 120591119909 (119864(120573)
119905) (119910) (78)
where
119864(120573)
119905(119910) =
2
1205871198892Γ (120573 + 1) (4119905)
120573+1+1198892119890minus11991024119905 (79)
Thus
119867120573 (119905) 119892 (119909) = 119892lowast119882119864(120573)
119905 (119909) (80)
In practice we use the integral formulation of (76)
119906 (119905 119909) = 119867120573 (119905) 119892 (119909) + 119866120573 (119891) (119905 119909)
= 119867120573 (119905) 119892 (119909) + int
119905
0
119867120573 (119905 minus 119904) 119891 (119904 119909) 119889119904
(81)
Remark 25 The function 119864(120573)119905
is the Gauss kernel associatedwith Weinstein operators This function satisfies
forall120585 isin R119889+1
+ F119882 (119864
(120573)
119905) (120585) = 119890
minus1199051205852
(82)
Proposition 26 Let 1 le 119901 le 119903 le infin and let 119891 isin 119871119901
120573(R119889+1
+)
Then the operator 119867120573(119905) maps 119871119901
120573(R119889+1
+) continuously to
119871119903
120573(R119889+1
+) and
10038171003817100381710038171003817119867120573 (119905) 119891
10038171003817100381710038171003817119871119903120573(R119889)
le 119862119905minus((119889+2120573+2)2)(1119901minus1119903)1003817
1003817100381710038171198911003817100381710038171003817119871119901
120573(R119889)
(83)
Moreover1003817100381710038171003817100381710038171003817
(minusΔ 120573)
1205752
119867120573 (119905) 119891
1003817100381710038171003817100381710038171003817119871119903120573(R119889)
le 119862119905minus1205752minus((119889+2120573+2)2)(1119901minus1119903)1003817
1003817100381710038171198911003817100381710038171003817119871119901
120573(R119889)
(84)
for all 120575 gt 0
Proof It follows from the relations (80) and (29) combinedwith scaling property of the kernel 119864(120573)
119905
In this section we prove estimates for the Weinstein heatsemigroupThese estimates are based on the following result
Lemma 27 Let C be an annulus Positive constants 119888 and 119862exist such that for any 119901 in [1infin] and any couple (119905 120582) ofpositive real numbers one has
suppF119882 (119906) sub 120582C 997904rArr
10038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
le 119862119890minus1198881199051205822
119906119871119901
120573(R119889+1+
)
(85)
8 Journal of Function Spaces and Applications
Proof We again consider a function Θ in 119863(R119889+1
+ 0) the
value of which is identically 1 in neighborhood of annulusCWe can also assume without loss of generality that 120582 = 1 Wethen have
119867120573 (119905) 119906 = 119892 (119905 sdot) lowast119882119906 (86)where
119892 (119905 sdot) = Fminus1
119882(Θ (120585) 119890
minus1199051205852
) (87)
The lemma is proved provided that we can find positive realnumbers 119888 and 119862 such that
forall119905 gt 01003817100381710038171003817119892 (119905 sdot)
10038171003817100381710038171198711120573(R119889+1+
)le 119862119890
minus119888119905 (88)
To begin we perform integrations by parts in (87) We get1003816100381610038161003816119892 (119905 119909)
1003816100381610038161003816=
1
119888120573
(1 + 1199092)
minus(119889+[2120573]+3)
times int
R119889+1+
Λ (119909 120585) (119868119889 minus Δ 120573)
119889+[2120573]+3
times (Θ (120585) 119890minus1199051205852
) 119889120583120573 (120585)
(89)
Using Leibnizrsquos formula we obtain1003816100381610038161003816119892 (119905 119909)
1003816100381610038161003816le 119862(1 + 119909
2)
minus(119889+[2120573]+3)
119890minus119888119905 (90)
and (88) follows
For any interval 119868 of R (bounded or unbounded) wedefine themixed space-time 119871119901(119868 119871119902
120573(R119889+1
+)) Banach space of
(classes of) measurable functions 119906 119868 rarr 119871119902
120573(R119889+1
+) such
that 119906119871119901(119868119871
119902
120573(R119889+1+
))lt infin with
119906119871119901(119868119871119902
120573(R119889+1+
))= (int
119868
119906 (119905 sdot)119901
119871119902
120573(R119889+1+
)119889119905)
1119901
if 1 le 119901 119902 lt infin
119906119871infin(119868119871119902
120573(R119889+1+
))= ess sup
119905isin119868
119906 (119905 sdot)119871119902
120573(R119889+1+
) if 1 le 119902 lt infin
(91)Corollary 28 Let C be an annulus and 120582 a positive realnumber Let 1199060 (resp 119891 = 119891(119905 119909)) satisfy suppF119882(1199060) sub 120582C(resp suppF119882(119891(119905 sdot)) sub 120582C for all 119905 in [0 119879]) Consider 119906 asolution of
120597119905119906 minus Δ 120573119906 = 0 119906|119905=0 = 1199060 (92)and V a solution of
120597119905V minus Δ 120573V = 119891 (119905 sdot) V|119905=0 = 0 (93)There exist positive constants 119888 and 119862 depending only on Csuch that for any 1 le 119886 le 119887 le infin and 1 le 119901 le 119902 le infin we have
119906119871119902([0119879]119871119887120573(R119889+1+
))le 119862120582
(119889+2120573+2)(1119886minus1119887)120582minus21199021003817
1003817100381710038171199060
1003817100381710038171003817119871119886120573(R119889+1+
)
V119871119902([0119879]119871119887120573(R119889+1+
))le 119862120582
minus2(1+1119902minus1119901)120582(119889+2120573+2)(1119886minus1119887)
times10038171003817100381710038171198911003817100381710038171003817119871119901([0119879]119871119886
120573(R119889+1+
))
(94)
Proof It suffices to use the fact that
119906 (119905 sdot) = 119867120573 (119905) 1199060 V (119905 sdot) = int119905
0
119867120573 (119905 minus 119904) 119891 (119904 sdot) 119889119904
(95)
Combining Lemma 27 and Youngrsquos inequality (29) withscaling property of the kernel 119864(120573)
119905now yields the result
Theorem 29 Let 119904 be a positive real number and (119901 119903) isin
[1infin]2 A constant 119862 exists which satisfies the following
property For 119906 isin Bminus2119904120573
119901119903 (R119889+1
+) one has
119862minus1119906
Bminus2119904120573
119901119903(R119889+1+
)le
10038171003817100381710038171003817100381710038171003817
10038171003817100381710038171003817119905119904119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
10038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
le 119862119906Bminus2119904120573
119901119903(R119889+1+
)
(96)
To prove this result we need the following lemma
Lemma 30 There exist two positive constants 120581 and 119862
depending only on 120593 such that for all 1 le 119901 le infin 120591 ge 0 and119895 isin Z one has
10038171003817100381710038171003817Δ 119895 (119867120573 (120591) 119906)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862119890
minus1205812211989512059110038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
) (97)
Proof The result follows immediately by applying Lemma 27and because Δ 119895(119867120573(120591))119906 = (119867120573(120591)Δ 119895)119906
Proof of Theorem 29 Using Lemma 30 and considering thefact that the operator Δ 119895 commutes with the operator 119867120573(119905)
and the definition of the homogeneous Weinstein-Besov(semi) norm we get
10038171003817100381710038171003817119905119904119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862119906
Bminus2119904120573
119901119903(R119889+1+
)sum
119895isinZ
11990511990422119895119904119890minus12058111990522119895
119888119903119895
(98)
where (119888119903119895)119895isinZ denotes as in all this proof a generic elementof the unit sphere of 119897119903(Z) In the case when 119903 = infin therequired inequality comes immediately from the followingeasy result For any positive 119904 we have
sup119905gt0
sum
119895isinZ
11990511990422119895119904119890minus12058111990522119895
lt infin (99)
In the case 119903 lt infin using the Holder inequality with theweight 22119895119904119890minus1205811199052
2119895
(99) and the Fubini theorem we obtain
int
infin
0
11990511990311990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)
119889119905
119905
le 119862119906119903
Bminus2119904120573
119901119903(R119889+1+
)int
infin
0
(sum
119895isinZ
11990511990422119895119904119890minus12058111990522119895
)
119903minus1
times (sum
119895isinZ
11990511990422119895119904119890minus12058111990522119895
119888119903
119903119895)
119889119905
119905
Journal of Function Spaces and Applications 9
le 119862119906119903
Bminus2119904120573
119901119903(R119889+1+
)int
infin
0
(sum
119895isinZ
11990511990422119895119904119890minus12058111990522119895
119888119903
119903119895)
119889119905
119905
le 119862119906119903
Bminus2119904120573
119901119903(R119889+1+
)sum
119895isinZ
119888119903
119903119895int
infin
0
(11990511990422119895119904119890minus12058111990522119895
)
119889119905
119905
le 119862Γ (119904) 119906119903
Bminus2119904120573
119901119903(R119889+1+
)
(100)
In order to prove the other inequality let us observe thatfor any 119904 greater than minus1 we have
Δ 119895119906 =
1
Γ (119904 + 1)
int
infin
0
119905119904(minusΔ 120573)
119904+1
119867120573 (119905) Δ 119895119906 119889119905 (101)
Then Lemma 30 Proposition 9 and the fact that the operatorΔ 119895 commutes with the operator119867120573(119905) lead to the following
10038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862int
infin
0
11990511990422119895(119904+1)
119890minus1205811199052211989510038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889119905
(102)
In the case 119903 = infin we simply write
10038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862(sup
119905gt0
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
times int
infin
0
22119895(119904+1)
119890minus12058111990522119895
119889119905
le 11986222119895119904(sup119905gt0
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
(103)
In the case 119903 lt infin Holderrsquos inequality with the weight 119890minus12058111990522119895
gives
(int
infin
0
119905119904119890minus1205811199052211989510038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889119905)
119903
le 1198622minus2119895(119903minus1)
int
infin
0
119905119903119904119890minus1205811199052211989510038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)119889119905
(104)
Thanks to (99) and Fubinirsquos theorem we infer from (102) that
sum
119895isinZ
2minus211989511990311990410038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)le 119862int
infin
0
11990511990311990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)
119889119905
119905
(105)
The theorem is proved
Second Proof ofTheorem 29We only consider the case 1 le 119903 ltinfinThe case 119903 = infin can be shown similarlyWe first prove that
119862minus1119906
Bminus2119904120573
119901119903(R119889+1+
)le
10038171003817100381710038171003817100381710038171003817
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
10038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
(106)
It is easy to see that
Δ 119895119906 = 120594119895lowast119882119864(120573)
2minus2119895lowast119882119906
(107)
where 120594119895 = Fminus1
119882(120593(2
minus119895120585)119890
2minus21198951205852
) and119864(120573)2minus2119895
is the Gauss kernelassociated with Weinstein operators By relation (29) we get
10038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le
10038171003817100381710038171003817120594119895
100381710038171003817100381710038171198711120573(R119889+1+
)
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
) (108)
As10038171003817100381710038171003817120594119895
100381710038171003817100381710038171198711120573(R119889+1+
)= int
R119889+1+
100381610038161003816100381610038161003816F
minus1
119882(120593 (120585) 119890
1205852
)
100381610038161003816100381610038161003816119889120583120573 (120585) lt infin (109)
we obtain10038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
) (110)
Moreover simple calculations give that
119864(120573)
2minus2119895lowast119882119906 = 119867120573 (2
minus4119895minus 119905
2) (119864
(120573)
1199052lowast119882119906)
(111)
Thus from Proposition 26 it follows that100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
100381710038171003817100381710038171003817119864(120573)
1199052lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1
+ )
(112)
for any 119905 isin [2minus119895minus1 2minus119895] which implies that
sum
119895isinZ
2minus211990411989511990310038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)
le 119862 sum
119895isinZ
int
2minus119895
2minus119895minus1(119905
2119904100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903119889119905
119905
le 119862int
infin
0
(1199052119904100381710038171003817100381710038171003817119864(120573)
1199052lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903119889119905
119905
le 119862int
infin
0
(11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903119889119905
119905
(113)
where we have used the fact that 119864(120573)1199052lowast119882119906 = 119867120573(119905
2)119906
We now prove that10038171003817100381710038171003817100381710038171003817
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
10038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
le 119862119906Bminus2119904120573
119901119903(R119889+1+
) (114)
Indeed one has
119864(120573)
2minus2119895lowast119882119906 = sum
119899isinZ
119864(120573)
2minus2119895lowast119882Δ 119899+119895119906 (115)
Arguing as above we have100381710038171003817100381710038171003817119864(120573)
1199052lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1
+ )
(116)
for any 119905 isin [2minus119895 21minus119895] Thus10038171003817100381710038171003817100381710038171003817
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
10038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
= 2
100381710038171003817100381710038171003817100381710038171003817
1003817100381710038171003817100381710038171199052119904119864(120573)
1199052lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)
100381710038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
le 119862 sum
119895isinZ
int
21minus119895
2minus119895(2
minus2119895119904100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903119889119905
119905
le 119862 sum
119895isinZ
(2minus2119895119904
sum
119899isinZ
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
(117)
10 Journal of Function Spaces and Applications
On the other hand it is easy to see that100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)le 1198622
minus211989911990410038171003817100381710038171003817Δ 119899+119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
) (118)
for any 119904 gt 0 For 0 lt 1199041 lt 119904 lt 1199042 and by using theMinkowskiinequality we have
sum
119895isinZ
(2minus2119895119904
sum
119899isinZ
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
le sum
119895isinZ
(2minus2119895119904
0
sum
minusinfin
2minus21198991199041
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
+ sum
119895isinZ
(2minus2119895119904
sum
119899isinN
2minus21198991199042
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
le 119862(
0
sum
minusinfin
2minus2119899(119904
1minus119904)(sum
119895isinZ
(2minus2(119899+119895)11990311990410038171003817
100381710038171003817Δ 119899+119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
)
1119903
)
119903
+ 119862(sum
N
2minus2119899(119904
2minus119904)(sum
119895isinZ
(2minus2(119899+119895)11990311990410038171003817
100381710038171003817Δ 119899+119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
)
1119903
)
119903
le 119862 sum
119895isinZ
2minus211989511990311990410038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)
(119)
The result is immediately from (117) and (119)
42 Embedding Sobolev Theorems
Theorem 31 Let 1 lt 119901 lt infin and let 0 lt 119904 lt (119889 + 2120573 +
2)119901There exists a positive constant119862 such that for all function119891 isin
H119904
119901120573(R119889+1
+) one has
10038171003817100381710038171198911003817100381710038171003817119871119902
120573(R119889+1+
)le 119862
10038171003817100381710038171198911003817100381710038171003817
1minus120579
H119904119901120573(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
120579
B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
) (120)
where 120579 = 119904119901(119889+2120573+2) and 119902 = 119901(119889+2120573+2)(119889+2120573+2minus119901119904)
Proof Bydensity we can suppose that119891belongs toSlowast(R119889+1
)It is easy to see that
119891 = int
infin
0
119867120573 (119905) Δ 120573119891119889119905(121)
and decompose the integral in two parts as follows
119891 = int
119860
0
119867120573 (119905) Δ 120573119891119889119905 + int
infin
119860
119867120573 (119905) Δ 120573119891119889119905(122)
where 119860 is a constant to be fixed laterOn the other hand byTheorem 29 we obtain10038171003817100381710038171003817119867120573 (119905) Δ 120573119891
10038171003817100381710038171003817119871infin120573(R119889+1+
)
le
119862
1199051minus(12)(119904minus(119889+2120573+2)119901)
10038171003817100381710038171198911003817100381710038171003817B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
)
(123)
Therefore after integrating we get
int
infin
119860
10038171003817100381710038171003817119867120573 (119905) Δ 120573119891
10038171003817100381710038171003817119871infin120573(R119889+1+
)119889119905
le 119860(12)(119904minus(119889+2120573+2)119901)1003817
1003817100381710038171198911003817100381710038171003817B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
)
(124)
On the other hand denoting 119892 = (minusΔ 120573)1199042119891 we have
119867120573 (119905) Δ 120573119891 =
1
(minus119905)1minus1199042
119867120573 (119905) (minus119905Δ 120573)
1minus1199042
119892 (125)
We proceed as in [8] we prove that1003816100381610038161003816100381610038161003816
119867120573 (119905) (minus119905Δ 120573)
1minus1199042
119892 (119909)
1003816100381610038161003816100381610038161003816
le 119862 (119904)119872120573 (119892) (119909) (126)
where119872120573(119892) is a maximal function of 119892 associated with theWeinstein operators (cf [12])
This leads to100381610038161003816100381610038161003816100381610038161003816
int
119860
0
119867120573 (119905) Δ 120573119891 (119909) 119889119905
100381610038161003816100381610038161003816100381610038161003816
le 1198621198601199042119872120573 (119892) (119909) (127)
In conclusion we get10038161003816100381610038161003816100381610038161003816
int
infin
0
119867120573 (119905) Δ 120573119891 (119909) 119889119905
10038161003816100381610038161003816100381610038161003816
le 119862 (1198601199042119872120573 (119892) (119909)
+119860(12)(119904minus(119889+2120573+2)119901)1003817
1003817100381710038171198911003817100381710038171003817B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
))
(128)
and the choice of 119860 such that
119860(119889+2120573+2)2119901
119872120573 (119892) (119909) =10038171003817100381710038171198911003817100381710038171003817B119904minus(119889+2120573+2)119901120573
infininfin (R119889+1+
)(129)
ensures that10038161003816100381610038161003816100381610038161003816
int
infin
0
119867120573 (119905) Δ 120573119891 (119909) 119889119905
10038161003816100381610038161003816100381610038161003816
le 119862(119872120573(119892)(119909))
1minus(119901119904(119889+2120573+2))10038171003817100381710038171198911003817100381710038171003817
119901119904(119889+2120573+2)
B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
)
(130)
Finally taking the 119871119902120573norm with 119902 = 119901(119889 + 2120573 + 2)(119889 + 2120573 +
2minus119901119904) ends the proof thanks to the fact themaximal function119872120573 is bounded of 119871119902
120573(R119889+1
+) into itself for 119902 gt 1
Theorem 32 Let 1 lt 119901 lt 119902 lt infin For all function 119891 such that119891 isin
H1199041
119901120573(R119889+1
+)⋂
Bminus120573120573
infininfin(R119889+1
+) one has
10038171003817100381710038171198911003817100381710038171003817H119904119901120573(R119889+1+
)le 119862
10038171003817100381710038171198911003817100381710038171003817
120579
H1199041
119901120573(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
1minus120579
Bminus120573120573
infininfin(R119889+1
+) (131)
where 120579 = 119901119902 119904 = 1205791199041 minus (1 minus 120579)120573 with 120573 gt 0 minus120573 lt 119904 lt 1199041
Proof It suffices to prove that1003817100381710038171003817100381710038171003817
(minusΔ 120573)
(119904minus1199041)2
119891
1003817100381710038171003817100381710038171003817119871119902
120573(R119889+1+
)
le 11986210038171003817100381710038171198911003817100381710038171003817
120579
119871119901
120573(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
1minus120579
Bminus120573minus1199041120573
infininfin (R119889+1+
)
(132)
Journal of Function Spaces and Applications 11
Indeed we use the following identity (which may be easilyproven by taking the Weinstein transform in 119909 of both sides)
(minusΔ 120573)
minus1205752
119891 (119909) =
1
Γ (1205752)
int
infin
0
1199051205752minus1
119867120573 (119905) 119891 (119909) 119889119905 (133)
with 120575 = 1199041 minus 119904 gt 0We decompose the integral in two parts as follows
(minusΔ 120573)
minus1205752
119891 (119909) =
1
Γ (1205752)
int
119879
0
1199051205752minus1
119867120573 (119905) 119891 (119909) 119889119905
+
1
Γ (1205752)
int
infin
119879
1199051205752minus1
119867120573 (119905) 119891 (119909) 119889119905
(134)
where 119879 is a constant to be fixed laterWe proceed as in [8] we obtain
10038161003816100381610038161003816119867120573 (119905) 119891 (119909)
10038161003816100381610038161003816le 119862119872120573 (119891) (119909) (135)
On the other hand we use Theorem 29 and the fact that 119891belongs to Bminus120573minus119904
1120573
infininfin(R119889+1
+) to deduce that
10038161003816100381610038161003816119867120573 (119905) 119891 (119909)
10038161003816100381610038161003816le 119862119905
(minus120573minus1199041)210038171003817100381710038171198911003817100381710038171003817Bminus120573minus1199041120573
infininfin (R119889+1+
) (136)
Thus by applying the preceding estimates on the right part of(134) we obtain
1003816100381610038161003816100381610038161003816
(minusΔ 120573)
minus1205752
119891 (119909)
1003816100381610038161003816100381610038161003816
le
1198621
Γ (1205752)
1198791205752119872120573 (119891) (119909)
+
1198622
Γ (1205752)
119879(120575minus120573minus119904
1)210038171003817100381710038171198911003817100381710038171003817Bminus120573minus1199041120573
infininfin (R119889+1+
)
(137)
We fix now
119879 = (
10038171003817100381710038171198911003817100381710038171003817Bminus120573minus1199041120573
infininfin (R119889+1+
)
119872120573 (119891) (119909)
)
2(120573+1199041)
(138)
We obtain
1003816100381610038161003816100381610038161003816
(minusΔ120573)
minus1205752
119891 (119909)
1003816100381610038161003816100381610038161003816
le
1198621 + 1198622
Γ (1205752)
(119872120573(119891)(119909))
12057910038171003817100381710038171198911003817100381710038171003817
1minus120579
Bminus120573minus1199041120573
infininfin (R119889+1+
)
(139)
Thus we deduce that1003817100381710038171003817100381710038171003817
(minusΔ120573)
minus1205752
119891
1003817100381710038171003817100381710038171003817119871119902
120573(R119889+1+
)
le
1198621 + 1198622
Γ (1205752)
10038171003817100381710038171003817119872120573 (119891)
10038171003817100381710038171003817
120579
119871119901
120573(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
1minus120579
Bminus120573minus1199041120573
infininfin (R119889+1+
)
(140)
To conclude we used the fact that the maximal function119872120573
is bounded of 119871119902120573(R119889+1
+) into itself for 119902 gt 1
43 Estimates in Generalized Besov Spaces For any interval 119868ofR (bounded or unbounded) and a normed space 119865(R119889+1
+)
we define the mixed space-time 119871119901(119868 119865(R119889+1
+)) space of
(classes of) measurable functions 119906 119868 rarr 119865(R119889+1
+) such that
||119906||119871119901(119868119865(R119889+1+
)) lt infin with
119906119871119901(119868119865(R119889+1+
)) = (int
119868
119906 (119905 sdot)119901
119865(R119889+1+
)119889119905)
1119901
if 1 le 119901 lt infin
119906119871infin(119868119865(R119889+1+
)) = ess sup119905isin119868
119906 (119905 sdot)119865(R119889+1+
)
(141)
For any interval 119868 of R (bounded or unbounded) anda Banach space 119883 we define the mixed space-time 119862(119868119883)space of continuous functions 119868 rarr 119883 When 119868 is bounded119862(119868119883) is a Banach space with the norm of 119871infin(119868 119883)
Theorem 33 Let 119904 isin R and 1 le 119901 119902 119903 le infin Let 119879 gt 0 119892 isin
B119904120573
119901119903(R119889+1
+) and119891 in 119871119902((0 119879) B
119904minus2+(2119902)120573
119901119903 (R119889+1
+)) Then (76)
has a unique solution
119906 isin 119871119902((0 119879)
B119904+(2119902)120573
119901119903(R
119889+1
+))
⋂119871infin((0 119879)
B119904120573
119901119903(R
119889+1
+))
(142)
and there exists a constant 119862 such that for all 1199021 isin [119902infin] onehas
1199061198711199021 ((0119879)B
119904+(21199021)120573
119901119903(R119889+1+
))
le 119862(10038171003817100381710038171198921003817100381710038171003817B119904120573
119901119903(R119889+1+
)+10038171003817100381710038171198911003817100381710038171003817119871119902((0119879)B
119904minus2+(2119902)120573
119901119903(R119889+1+
)))
(143)
If in addition 119903 lt infin then 119906 isin 119862([0 119879] B119904120573
119901119903(R119889+1
+))
Proof Since 119892 and 119891 are temperate distributions (76) has aunique solution 119906 in S1015840
((0 119879) timesR119889+1
+) which satisfies
F119882 (119906) (119905 120585) = 119890minus1199051205852
F119882 (119892) (120585)
+ int
119905
0
119890(120591minus119905)120585
2
F119882 (119891) (120591 120585) 119889120591
(144)
Next we notice that applying Δ 119895 to (76) and using formula(81) yield
Δ 119895119906 (119905 sdot) = 119867120573 (119905) Δ 119895119892 + int
119905
0
119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot) 119889120591(145)
Therefore
10038171003817100381710038171003817Δ 119895119906 (119905 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le
10038171003817100381710038171003817119867120573(119905)Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+ int
119905
0
10038171003817100381710038171003817119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591
(146)
12 Journal of Function Spaces and Applications
By virtue of Lemma 30 we thus have for some 120581 gt 0
10038171003817100381710038171003817Δ 119895119906(119905 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
le 119862[119890minus1205812211989511990510038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+ int
119905
0
119890minus12058122119895(119905minus120591) 10038171003817
100381710038171003817Δ 119895119891 (120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591]
(147)
Applying convolution inequalities we get
10038171003817100381710038171003817Δ 119895119906
100381710038171003817100381710038171198711199021 ((0119879)119871
119901
120573(R119889+1+
))
le 119862[
[
((
1 minus 119890minus120581119879119902122119895
120581119902122119895
)
11199021
)
10038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+((
1 minus 119890minus120581119879119902222119895
120581119902222119895
)
11199022
)
10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119902((0119879)119871
119901
120573(R119889+1+
))
]
]
(148)
with 11199022 = 1+ 11199021 minus1119902 Finally taking the 119897119903(Z) norm we
conclude that (with the usual convention if 119903 = infin)
1199061198711199021 ((0119879)B
119904+(21199021)120573
119901119903(R119889+1+
))
le 119862[
[
sum
119895isinZ
((
1 minus 119890minus120581119879119902122119895
120581119902122119895
)
1199031199021
)(211989511990410038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
]
]
1119903
+ 119862[
[
sum
119895isinZ
((
1 minus 119890minus120581119879119902222119895
120581119902222119895
)
1199031199022
)
times (2119895(119904minus2+2119902)10038171003817
100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119902(0119879119871
119901
120573(R119889+1+
))
119903
]
]
1119903
(149)
which insures that 119906 isin 119871119902((0 119879)
B119904+(2119902)120573
119901119903 (R119889+1
+))
⋂119871infin((0 119879)
B119904120573
119901119903(R119889+1
+)) and yields the desired inequality
Since 119906 belongs to 119862([0 119879]B119904120573
119901119903(R119889+1
+)) in the case where
119903 is finite may be easily deduced from the density ofSlowast(R
119889+1)⋂
B119904120573
119901119903(R119889+1
+) in B
119904120573
119901119903(R)
Theorem 34 Let 119904 isin R 119879 gt 0 and 1 le 119901 119902 119903 le infinOne supposes that 119892 isin 119861
119904120573
119901119903(R119889+1
+) and 119891 isin 119871
119902((0 119879)
119861119904minus2+(2119902)120573
119901119903 (R119889+1
+)) Then (76) has a unique solution 119906 belong-
ing to
119871119902((0 119879) 119861
119904+(2119902)120573
119901119903(R
119889+1
+))⋂119871
infin((0 119879) 119861
119904120573
119901119903(R
119889+1
+))
(150)
and there exists a constant 119862 such that for all 119902 le 1199021 le infin
1199061198711199021 ((0119879)119861
119904+(21199021)120573
119901119903(R119889+1+
))
le 119862 [ (1 + 11987911199021)10038171003817100381710038171198921003817100381710038171003817119861119904120573
119901119903(R119889+1+
)
+ (1 + 1198791+1119902
1minus1119902
)10038171003817100381710038171198911003817100381710038171003817119871119902((0119879)119861
119904minus2+(2119902)120573
119901119903(R119889+1+
))]
(151)
If in addition 119903 lt infin then 119906 isin 119862([0 119879] 119861119904120573119901119903(R119889+1
+))
Proof Since 119892 119891 are tempered (76) has a unique solution 119906in S1015840
((0 119879) timesR119889+1
+) satisfying
F119882 (119906) (119905 120585) = 119890minus1199051205852
F119882 (119892) (120585)
+ int
119905
0
119890(120591minus119905)120585
2
F119882 (119891) (120591 120585) 119889120591
(152)
Hence applying Δ 119895 119895 ge 0 to (81) we see that
Δ 119895119906 (119905 sdot) = 119867120573 (119905) Δ 119895119892 + int
119905
0
119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot) 119889120591(153)
and thus by Lemma 30 we can deduce that10038171003817100381710038171003817Δ 119895119906 (119905 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
le
10038171003817100381710038171003817119867120573(119905)Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)+ int
119905
0
10038171003817100381710038171003817119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591
le 119862[119890minus1205812211989511990510038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+int
119905
0
119890minus12058122119895(119905minus120591)10038171003817
100381710038171003817Δ 119895119891(120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591]
(154)
Then it follows from convolution inequalities thatΔ 1198951199061198711199021 ((0119879)119871
119901
120573(R119889+1+
))is dominated by
(
1 minus 119890minus120581119879119902122119895
120581119902122119895
)
11199021
10038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119861119904120573
119901119903(R119889+1+
)
+ (
1 minus 119890minus120581119879119902222119895
120581119902222119895
)
11199022
10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119902((0119879)119871
119901
120573(R119889+1+
))
(155)
with 11199022 = 1 + 11199021 minus 1119902 Moreover similarly as above wecan obtain that
1003817100381710038171003817Δminus1119906(119905 sdot)
1003817100381710038171003817119871119901
120573(R119889+1+
)le1003817100381710038171003817Δminus1119892
1003817100381710038171003817119871119901
120573(R119889+1+
)
+ int
119905
0
1003817100381710038171003817Δminus1119891 (120591 sdot)
1003817100381710038171003817119871119901
120573(R119889+1+
)119889120591
(156)
and thus if 1 le 119902 le 1199021 le infin1003817100381710038171003817Δminus1119906
10038171003817100381710038171198711199021 ((0119879)119871
119901
120573(R119889+1+
))
le 119862(119879111990211003817100381710038171003817Δminus1119892
1003817100381710038171003817119871119901
120573(R119889+1+
)+ 119879
111990221003817100381710038171003817Δminus1119891
1003817100381710038171003817119871119902((0119879)119871
119901
120573(R119889+1+
)))
(157)
Journal of Function Spaces and Applications 13
Finally taking the 119897119903-normwith respect to 119895 in (155) and (157)with the usual convention if 119903 = infin we can deduce the desiredestimate
Acknowledgment
Theauthor gratefully acknowledges theDeanship of ScientificResearch at the University of Taibah The author is deeplyindebted to the referee for providing constructive commentsand help in improving the contents of this paper
References
[1] Z Ben Nahia and N Ben Salem ldquoSpherical harmonics andapplications associated with the Weinstein operatorrdquo in Pro-ceedings of the International Conference on PotentialTheory heldin Kouty Czech Republic (ICPT rsquo94) pp 235ndash241 1996
[2] Z Ben Nahia and N Ben Salem ldquoOn a mean value propertyassociated with the Weinstein operatorrdquo in Proceedings of theInternational Conference on Potential Theory held in KoutyCzech Republic (ICPT rsquo94) pp 243ndash253 1996
[3] M Brelot ldquoEquation de Weinstein et potentiels de MarcelRieszrdquo in Seminaire de Theorie de Potentiel Paris No 3 vol 681of Lecture Notes in Mathematics pp 18ndash38 Springer BerlinGermany 1978
[4] H Mejjaoli and M Salhi ldquoUncertainty principles for theweinstein transformrdquo Czechoslovak Mathematical Journal vol61 no 4 pp 941ndash974 2011
[5] H Mejjaoli and A Ould Ahmed Salem ldquoWeinstein Gabortransform and applicationsrdquo Advanced Studies in Pure Mathe-matics vol 2 no 3 pp 203ndash210 2012
[6] H Mejjaoli ldquoBesov spaces associated withthe Weinstein opera-tor and applicationsrdquo In press
[7] T Kawazoe and H Mejjaoli ldquoGeneralized Besov spaces andtheir applicationsrdquo Tokyo Journal of Mathematics vol 35 no 2pp 297ndash320 2012
[8] H Mejjaoli ldquoLittlewood-Paley decomposition associated withthe Dunkl operators and paraproduct operatorsrdquo Journal ofInequalities in Pure and Applied Mathematics vol 9 no 4 pp1ndash25 2008
[9] H Mejjaoli and N Sraeib ldquoGeneralized sobolev spaces inquantum calculus and applicationsrdquo Journal of Inequalities andSpecial Functions vol 1 no 4 pp 43ndash64 2012
[10] H Mejjaoli ldquoGeneralized homogeneous Besov spaces and theirapplicationsrdquo Serdica Mathematical Journal vol 38 no 4 pp575ndash614 2012
[11] H Triebel Interpolation Theory Functions Spaces DifferentialOperators North-Holland AmsterdamThe Netherlands 1978
[12] V S Guliev ldquoOn maximal function and fractional integralassociated with the Bessel differential operatorrdquo MathematicalInequalities and Applications vol 6 no 2 pp 317ndash330 2003
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Journal of Function Spaces and Applications 3
(i) For 119891 in 1198711120573(R119889+1
+)
1003817100381710038171003817F119882 (119891)
1003817100381710038171003817119871infin120573(R119889+1+
)le100381710038171003817100381711989110038171003817100381710038171198711120573(R119889+1+
) (18)
(ii) For 119891 in Slowast(R119889+1
) we have
F119882 (Δ 120573119891) (119910) = minus10038171003817100381710038171199101003817100381710038171003817
2F119882 (119891) (119910) forall119910 isin R
119889+1
+ (19)
(iii) For all 119891 in 1198711120573(R119889+1
+) ifF119882(119891) belongs to 119871
1
120573(R119889+1
+)
then
119891 (119910) = 119862 (120573)int
R119889+1+
F119882 (119891) (119909) Λ (119909 119910) 119889120583120573 (119909) ae
(20)
where
119862 (120573) =
1
1205871198894120573+1198892
(Γ (120573 + 1))2 (21)
(iv) For 119891 isin Slowast(R119889+1
) if we define
F119882 (119891) (119910) = F119882 (119891) (minus119910) (22)
then
(F119882)minus1=
1
119862 (120573)
F119882 (23)
Proposition 1 (see [2]) (i) the Weinstein transform F119882 is atopological isomorphism fromSlowast(R
119889+1) onto itself and for all
f in Slowast(R119889+1
)
int
R119889+1+
1003816100381610038161003816119891 (119909)
1003816100381610038161003816
2119889120583120573 (119909) = 119862 (120573)int
R119889+1+
1003816100381610038161003816F119882 (119891) (120585)
1003816100381610038161003816
2119889120583120573 (120585)
(24)
(ii) In particular the renormalized Weinstein transform119891 rarr 119862(120573)
12F119882(119891) can be uniquely extended to an isometric
isomorphism from 1198712
120573(R119889+1
+) onto itself
In the Fourier analysis the translation operator is givenby 119891 997891rarr 119891(sdot + 119909)
In harmonic analysis associated for the operator Δ 120573 thegeneralized translation operator 120591119909 119909 isin R119889+1
+is defined by
forall119910 isin R119889+1
+
120591119909119891 (119910) =
Γ (120573 + 1)
radic120587Γ (120573 + 12)
times int
120587
0
119891(1199091015840+ 119910
1015840 radic119909
2
119889+1+ 119910
2
119889+1+ 2119909119889+1119910119889+1 cos 120579)
times (sin 120579)2120573119889120579(25)
where 119891 isin 119862lowast(R119889+1
)
By using the Weinstein kernel we can also define ageneralized translation For functions 119891 isin Slowast(R
119889+1) and
119910 isin R119889+1
+the generalized translation 120591119910119891 is defined by the
following relation
F119882 (120591119910119891) (119909) = Λ (119909 119910)F119882 (119891) (119909) (26)
By using the generalized translation we define the general-ized convolution product119891lowast
119882119892 of functions119891 119892 isin 1198711
120573(R119889+1
+)
as follows
119891lowast119882119892 (119909) = int
R119889+1+
120591119909119891 (minus1199101015840 119910119889+1) 119892 (119910) 119889120583120573 (119910) (27)
This convolution is commutative and associative and itsatisfies the following
(i) For all 119891 119892 isin 1198711
120573(R119889+1
+) 119891lowast119882 119892 belongs to 1198711
120573(R119889+1
+)
and
F119882 (119891lowast119882119892) = F119882 (119891)F119882 (119892) (28)
(ii) Let 1 le 119901 119902 119903 le infin such that 1119901 + 1119902 minus 1119903 = 1If 119891 isin 119871
119901
120573(R119889+1
+) and 119892 isin 119871
119902
120573(R119889+1
+) then 119891lowast119882119892 isin
119871119903
120573(R119889+1
+) and
1003817100381710038171003817119891lowast119882119892
1003817100381710038171003817119871119903120573(R119889+1+
)le10038171003817100381710038171198911003817100381710038171003817119871119901
120573(R119889+1+
)
10038171003817100381710038171198921003817100381710038171003817119871119902
120573(R119889+1+
) (29)
We define the tempered distribution T119891 associated with119891 isin 119871
119901
120573(R119889+1
+) by
⟨T119891 120601⟩ = int
R119889+1+
119891 (119909) 120601 (119909) 119889120583120573 (119909) (30)
for 120601 isin Slowast(R119889+1
) and denote by ⟨119891 120601⟩120573 the integral in therighthand side
Definition 2 The Weinstein transform F119882(120591) of a distribu-tion 120591 isin S1015840
lowast(R119889+1
) is defined by
⟨F119882 (120591) 120601⟩ = ⟨120591F119882 (120601)⟩ (31)
for 120601 isin Slowast(R119889+1
)
In particular for 119891 isin 119871119901
120573(R119889+1
+) it follows that for 120601 isin
Slowast(R119889+1
)
⟨F119882 (119891) 120601⟩ = ⟨F119882 (T119891) 120601⟩ = ⟨T119891F119882 (120601)⟩
= ⟨119891F119882 (120601)⟩120573
(32)
Proposition 3 The Weinstein transform F119882 is a topologicalisomorphism from S1015840
lowast(R119889+1
) onto itself
Definition 4 The generalized convolution product of a dis-tribution 119878 in S1015840
lowast(R119889+1
) and a function 120601 in Slowast(R119889+1
) is thefunction 119878lowast119882120601 defined by
119878lowast119882 120601 (119909) = ⟨119878119910 120591minus119910120601 (119909)⟩ (33)
4 Journal of Function Spaces and Applications
Proposition 5 Let 119891 be in 119871119901
120573(R119889+1
+) 1 le 119901 le infin and 120601
in Slowast(R119889+1
) Then the distribution T119891lowast119882120601 is given by thefunction 119891lowast119882120601 and T119891lowast119882120601 belongs to 119871119901
120573(R119889+1
+) Moreover
for all 120595 isin Slowast(R119889+1
)
⟨T119891lowast119882120601 120595⟩ = ⟨
119891 120601lowast119882 ⟩120573 (34)
where (119909) = 120595(minus119909) and
F119882 (T119891lowast119882 120601) = F119882 (T119891)F119882 (120601) (35)
For each 119906 isin S1015840
lowast(R119889+1
) we define the distribution Δ 120573119906
by ⟨Δ 120573119906 120595⟩ = ⟨119906 Δ 120573120595⟩ and this distribution satisfies thefollowing property
F119882 (Δ 120573119906) = minus10038171003817100381710038171199101003817100381710038171003817
2F119882 (119906) (36)
In the following we denote T119891 given by (30) by 119891 forsimplicity
3 B119904120573
119901119902 F119904120573
119901119902(R119889+1
+) H119904
119901120573Spaces and
Basic Properties
31 HomogeneousWeinstein-Littlewood-Paley DecompositionOne of the main tools in this paper is the homogeneousLittlewood-Paley decomposition of distribution associatedwith theWeinstein operators into dyadic blocs of frequencies
Lemma6 One defines byC the ring of center 0 of small radius12 and great radius 2 There exists two radial functions 120595 and120593 the values of which are in the interval [0 1] belonging to119863lowast(R
119889+1) such that
supp120595 sub 119861 (0 1) supp120593 sub C
forall120585 isin R119889+1
120595 (120585) + sum
119895ge0
120593 (2minus119895120585) = 1
forall120585 isin C sum
119895isinZ
120593 (2minus119895120585) = 1
|119899 minus 119898| ge 2 997904rArr supp120593 (2minus119899sdot) cap supp120593 (2minus119898sdot) = 0
119895 ge 1 997904rArr supp120595 cap supp120593 (2minus119895sdot) = 0
(37)
Notations We denote by
Δ 119895119891 = Fminus1
119882(120593(
120585
2119895)F119882 (119891))
119878119895119891 = sum
119899le119895minus1
Δ 119899119891 forall119895 isin Z(38)
The distribution Δ 119895119891 is called the 119895th dyadic block of thehomogeneous Littlewood-Paley decomposition of 119891 associ-ated with the Weinstein operators
Throughout this paper we define 120601 and 120594 by 120601 = Fminus1
119882(120593)
and 120594 = Fminus1
119882(120595)
When dealing with the Littlewood-Paley decompositionit is convenient to introduce the functions and 120593 belongingto119863lowast(R
119889+1) such that equiv 1 on supp120595 and 120593 equiv 1 on supp120593
Remark 7 We remark that
F119882 (119878119895119891) (120585) = (
120585
2119895)F119882 (119878119895119891) (120585)
F119882 (Δ 119895119891) (120585) = 120593(
120585
2119895)F119882 (Δ 119895119891) (120585)
(39)
We put
120601 = F
minus1
119882(120593) 120594 = F
minus1
119882() (40)
Definition 8 One denotes by S1015840
ℎ120573lowast(R119889+1
) the space oftempered distribution such that
lim119895rarrminusinfin
119878119895119906 = 0 in S1015840
lowast(R
119889+1) (41)
Proposition 9 (Bernstein inequalities) For all 120583 isin N119889+1 and120590 isin R for all 119895 isin Z for all 1 le 119901 119902 le infin and for all119891 isin S1015840
lowast(R119889+1
) one has the following
(i) 10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119902
120573(R119889+1+
)
le
10038171003817100381710038171003817
120601
10038171003817100381710038171003817119871119903120573(R119889+1+
)
10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119901
120573(R119889+1+
)2119895(119889+2120573+2)(1119901minus1119902)
with 1
119902
=
1
119901
+
1
119903
minus 1
(ii) 10038171003817100381710038171003817119878119895119891
10038171003817100381710038171003817119871119902
120573(R119889+1+
)
le10038171003817100381710038171205941003817100381710038171003817119871119903120573(R119889+1+
)
10038171003817100381710038171003817119878119895119891
10038171003817100381710038171003817119871119901
120573(R119889+1+
)2119895(119889+2120573+2)(1119901minus1119902)
with 1
119902
=
1
119901
+
1
119903
minus 1
(iii)1003817100381710038171003817100381710038171003817
(radicminusΔ 120573)
120590
Δ 119895119891
1003817100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)
le
10038171003817100381710038171003817F
minus1
119882(10038171003817100381710038171205851003817100381710038171003817
120590120593)
100381710038171003817100381710038171198711120573(R119889+1+
)
times
10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119901
120573(R119889+1+
)2119895120590
(42)
Proof Using Remark 7 we deduce from Proposition 5 that
119878119895119891 = 2119895(119889+2120573+2)
120594 (2119895sdot) lowast119882119878119895119891
Δ 119895119891 = 2119895(119889+2120573+2)
120601 (2119895sdot) lowast119882Δ 119895119891
(43)
Thus from the relation (29) we prove (i) (ii) and (iii)
32 Definitions In the following we define analogues of thehomogeneous Besov Triebel-Lizorkin and Riesz potentialspaces associated with the Weinstein operators on R119889+1
+and
obtain their basic propertiesFrom now we make the convention that for all non-
negative sequence 119886119902119902isinZ the notation (sum119902119886119903
119902)1119903 stands for
sup119902119886119902 in the case 119903 = infin
Journal of Function Spaces and Applications 5
Definition 10 Let 119904 isin R and 119901 119902 isin [1infin]The homogeneousWeinstein-Besov spaces B
119904120573
119901119902(R119889+1
+) are the spaces of distri-
bution in S1015840
ℎ120573lowast(R119889+1
) such that
10038171003817100381710038171198911003817100381710038171003817B119904120573
119901119902(R119889+1+
)= (sum
119895isinZ
(211990411989510038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119902
)
1119902
lt infin (44)
Proposition 11 (see [6]) Let 119904 isin R and 119901 and 119902 two elementsof [1infin] the space B
119904120573
119901119902(R119889+1
+) is the set of 119891 isin S1015840
ℎ120573lowast(R119889+1
)
verifying
10038171003817100381710038171003817
119891
10038171003817100381710038171003817B119904120573
119901119902(R119889+1+
)= (int
infin
0
(119905minus1199041003817100381710038171003817119891lowast119882120601119905
1003817100381710038171003817119871119901
120573(R119889+1+
))
119902119889119905
119905
)
1119902
lt infin
(45)
where 120601119905(119909) = (11199052120573+2+119889
)120601(119909119905) for all 119905 isin (0infin) and 119909 isin
R119889+1
+
Definition 12 For 119904 isin R and 119901 119902 isin [1infin] one writes10038171003817100381710038171198911003817100381710038171003817119861119904120573
119901119902(R119889+1+
)=10038171003817100381710038171198780119891
1003817100381710038171003817119871119901
120573(R119889+1+
)
+ (sum
119895ge1
(211990411989510038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119902
)
1119902
(46)
The nonhomogeneous Besov space 119861119904120573119901119902(R119889+1
+) associated
with the Weinstein operators is defined by
119861119904120573
119901119902(R
119889+1
+) = 119891 isin S
1015840(R
119889)
10038171003817100381710038171198911003817100381710038171003817119861119904120573
119901119902(R119889+1+
)lt infin (47)
We give now another definition equivalent to the nonho-mogeneous Besov space 119861119904120573119901119902(R119889+1
+)
Proposition 13 Let 119904 isin R and119901 and 119902 two elements of [1infin]the space 119861119904120573119901119902(R119889+1
+) is the set of 119891 isin S1015840
(R119889) verifying
10038171003817100381710038171003817
119891
10038171003817100381710038171003817119861119904120573
119901119902(R119889+1+
)=1003817100381710038171003817119891lowast119882120595
1003817100381710038171003817119871119901
120573(R119889+1+
)
+ (int
1
0
(119905minus1199041003817100381710038171003817119891lowast119882120601119905
1003817100381710038171003817119871119901
120573(R119889+1+
))
119902119889119905
119905
)
1119902
lt infin
(48)
Definition 14 Let 119904 isin R and 1 le 119901 119902 le infin the homogeneousWeinstein-Triebel-Lizorkin space F
119904120573
119901119902(R119889+1
+) is the space of
distribution in S1015840
ℎ120573lowast(R119889+1
) such that
10038171003817100381710038171198911003817100381710038171003817F119904120573
119901119902(R119889+1+
)=
100381710038171003817100381710038171003817100381710038171003817100381710038171003817
(sum
119895isinZ
211990411989511990210038161003816100381610038161003816Δ 119895119891
10038161003816100381610038161003816
119902
)
1119902100381710038171003817100381710038171003817100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)
lt infin (49)
Definition 15 For 119904 isin R the operatorR119904
120573from S1015840
ℎ120573lowast(R119889+1
)
to S1015840
ℎ120573lowast(R119889+1
) is defined by
R119904
120573(119891) = F
minus1
119882(sdot
119904F119882119891) (50)
The operatorRminus119904
120573is called Weinstein-Riesz potential space
Definition 16 For 119904 isin R and 1 le 119901 le infin the homogeneousWeinstein-Riesz potential space H119904
119901120573(R119889+1
+) is defined
as the space Rminus119904
120573(119871
119901
120573(R119889+1
+)) equipped with the norm
119891H119904119901120573(R119889+1+
)= R119904
120573(119891)
119871119901
120573(R119889+1+
)
Proposition 17 Let 119904 isin R and 1 le 119901 119902 le infinThe operator Δ 120573 is a linear continuous operator from
B119904120573
119901119902(R119889+1
+) into B
119904minus2120573
119901119902 (R119889+1
+) and from H119904
119901120573(R119889+1
+) into
H119904minus2
119901120573(R119889+1
+)
Proof We obtain these results by the similar ideas used in thenonhomogeneous case (cf [6])
Proposition 18 Let 119904 119905 isin R and 1 le 119901 119902 le infin The operatorR119905
120573is a linear continuous injective operator from B
119904120573
119901119902(R119889+1
+)
onto B119904minus119905120573
119901119902 (R119889+1
+) and from H119904
119901120573(R119889+1
+) onto H119904minus119905
119901120573(R119889+1
+)
Proof We obtain these results by the similar ideas used in thenonhomogeneous case (cf [6])
33 Embeddings As in the Euclidean case (cf [11]) themono-tone character of 119897119902-spaces and the Minkowskis inequalityyield the following
Proposition 19 If 1 le 1199021 lt 1199022 le infin one has
B119904120573
1199011199021
(R119889+1
+) 997893rarr
B119904120573
1199011199022
(R119889+1
+) (1 le 119901 le infin 119904 isin R)
(51)
MoreoverB119904120573
1199011(R
119889+1
+) 997893rarr
H119904
119901120573(R
119889+1
+) 997893rarr
B119904120573
119901infin(R
119889+1
+)
(1 le 119901 le infin 119904 isin R)
(52)
If 1199040 = 1199041 one also has
(H1199040
119901120573(R
119889+1
+)
H1199041
119901120573(R
119889+1
+))
120579119902=
B119904120573
119901119902(R
119889+1
+)
(1 le 119901 119902 le infin 120579 isin (0 1))
(53)
where 119904 = (1 minus 120579)1199040 + 1205791199041
Proposition 20 One assumes that 119904 minus (119889 + 2120573 + 2)119901 = 1199041 minus
(119889 + 2120573 + 2)1199011 Then the following inclusion holds
B119904120573
119901119902(R
119889+1
+) 997893rarr
B1199041120573
11990111199021
(R119889+1
+)
(1 le 119901 le 1199011 le infin 1 le 119902 le 1199021 le infin 119904 1199041 isin R)
(54)
Proof In order to prove the inclusion we use the estimate
Δ 119895119891 = 2119895(119889+2120573+2)
120601 (2119895sdot) lowast119882Δ 119895119891 (55)
Proposition 9(i) gives that10038171003817100381710038171003817Δ 119895119891
100381710038171003817100381710038171198711199011
120573(R119889+1+
)=
100381710038171003817100381710038172119895(119889+2120573+2)
120601 (2119895sdot) lowast119882Δ 119895119891
100381710038171003817100381710038171198711199011
120573(R119889+1+
)
le 1198622119895(119889+2120573+2)(1119901minus1119901
1)10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
(56)
6 Journal of Function Spaces and Applications
By definition of the homogeneous Weinstein-Besov spaceswe therefore infer10038171003817100381710038171198911003817100381710038171003817B1199041120573
11990111199021(R119889+1+
)
= (
infin
sum
119895=minusinfin
(2119895119904110038171003817100381710038171003817Δ 119895119891
100381710038171003817100381710038171198711199011
120573(R119889+1+
))
1199021
)
11199021
le 119862(sum
119895isinZ
(211989511990412119895(119889+2120573+2)(1119901minus1119901
1)10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
1199021
)
11199021
le 119862(sum
119895isinZ
(211989511990410038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
1199021
)
11199021
le 11986210038171003817100381710038171198911003817100381710038171003817B119904120573
119901119902(R119889+1+
)
(57)
since 119902 le 1199021 This gives the inclusion
Proposition 21 (1) If 119906 belongs to B119904120573
119901119902(R119889+1
+) cap
B119905120573
119901119902(R119889+1
+)
then 119906 belongs to B120579119904+(1minus120579)119905120573
119901119902 (R119889+1
+) for all 120579 isin [0 1] and
119906B120579119904+(1minus120579)119905120573
119901119902(R119889+1+
)le 119906
120579
B119904120573
119901119902(R119889+1+
)119906
1minus120579
B119905120573
119901119902(R119889+1+
) (58)
(2) If 119906 belongs to B119904120573
119901infin(R119889+1
+) cap
B119905120573
119901infin(R119889+1
+) and 119904 lt 119905
then 119906 belongs to B120579119904+(1minus120579)119905120573
1199011(R119889+1
+) for all 120579 isin (0 1) and there
exists a positive constant 119862(119905 119904) such that
119906B120579119904+(1minus120579)119905120573
1199011(R119889+1+
)le 119862 (119905 119904) 119906
120579
B119904120573
119901infin(R119889+1+
)119906
1minus120579
B119905120573
119901infin(R119889+1+
) (59)
(3) If 119906 belongs to B119904120573
119901infin(R119889+1
+) cap
B119904+120576120573
119901infin (R119889+1
+) and 120576 gt
0 then 119906 belongs to B119904120573
1199011(R119889+1
+) and there exists a positive
constant 119862 such that
119906B119904120573
1199011(R119889+1+
)le
119862
120576
119906B119904120573
119901infin(R119889+1+
)log
2(119890 +
119906B119904+120576120573
119901infin(R119889+1+
)
119906B119904120573
119901infin(R119889+1+
)
)
(60)
Proof (1) is obvious from the Holderrsquos inequality As for (2)we write 119906
B120579119904+(1minus120579)119905120573
1199011(R119889+1+
)as
sum
119895le119873
2119895(120579119904+(1minus120579)119905)10038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)+ sum
119895gt119873
2119895(120579119904+(1minus120579)119905)10038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
(61)
where 119873 is chosen here after By the definition of thehomogeneous Weinstein-Besov norms we see that
2119895(120579119904+(1minus120579)119905)10038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 2
119895(1minus120579)(119905minus119904)119906
B119904120573
119901infin(R119889+1+
)
2119895(120579119904+(1minus120579)119905)10038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 2
minus119895120579(119905minus119904)119906
B119905120573
119901infin(R119889+1+
)
(62)
and thus 119906B120579119904+(1minus120579)119905120573
1199011(R119889+1+
)is dominated by
119906B119904120573
119901infin(R119889+1+
)sum
119895le119873
2119895(1minus120579)(119905minus119904)
+ 119906B119905120573
119901infin(R119889+1+
)sum
119895gt119873
2minus119895120579(119905minus119904)
le 119862119906B119904120573
119901infin(R119889+1+
)
2(119873+1)(1minus120579)(119905minus119904)
2(1minus120579)(119905minus119904)
minus 1
+ 119906B119905120573
119901infin(R119889+1+
)
2minus119873120579(119905minus119904)
1 minus 2minus120579(119905minus119904)
(63)
Hence in order to complete the proof of (2) it suffices tochoose119873 such that
119906B119905120573
119901infin(R119889)
119906B119904120573
119901infin(R119889)
le 2119873(119905minus119904)
lt 2
119906B119905120573
119901infin(R119889)
119906B119904120573
119901infin(R119889)
(64)
As for (3) it is easy to see that 119906B119904120573
1199011(R119889+1+
)is dominated as
sum
119895le119873minus1
211989511990410038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)+ sum
119895ge119873
211989511990410038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
le (119873 + 1) 119906B119904120573
119901infin(R119889+1+
)+
2minus(119873minus1)120576
2120576minus 1
119906B119904+120576120573
119901infin(R119889+1+
)
(65)
Hence letting
119873 = 1 + [
[
1
120576
log2
119906B119904+120576120573
119901infin(R119889+1+
)
119906B119904120573
119901infin(R119889+1+
)
]
]
(66)
we can obtain the desired estimate
Proposition 22 Let 119902 isin (1infin) and let 119904 isin R such that0 lt 119904 lt (119889 + 2120573 + 2)119902 then one has
B119904120573
119902119902(R
119889+1
+) =
F119904120573
119902119902(R
119889+1
+) 997893rarr
F119904120573
119902infin(R
119889+1
+)
997893rarrF119904minus((119889+2120573+2)119902)120573
infininfin(R
119889+1
+)
(67)
H119904
119902120573(R
119889+1
+) =
F119904120573
1199022(R
119889+1
+) 997893rarr
F119904120573
119902infin(R
119889+1
+)
997893rarrF119904minus((119889+2120573+2)119902)120573
infininfin(R
119889+1
+)
(68)
Proof We obtain these results by the similar ideas used in thenonhomogeneous case (cf [6])
Theorem 23 Let 119886 119887 gt 0 and let 1199021 1199022 isin [1infin] Let120579 = 119886(119886 + 119887) isin (0 1) and let 1119901 = (1 minus 120579)1199021 +
1205791199022 Then there exists a constant 119862 such that for every119891 isin
F119886120573
1199021infin(R119889+1
+) cap
Fminus119887120573
1199022infin(R119889+1
+) then one has
1003816100381610038161003816119891 (119909)
1003816100381610038161003816le 119862(sup
119895isinZ
2119886119895 10038161003816100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
1minus120579
(sup119895isinZ
2minus119887119895 10038161003816
100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
120579
(69)
In particular one gets
10038171003817100381710038171198911003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
10038171003817100381710038171198911003817100381710038171003817
1minus120579
F119886120573
1199021infin(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
120579
Fminus119887120573
1199022infin(R119889+1+
) (70)
Journal of Function Spaces and Applications 7
Proof Let 119891 be a Schwartz class we have
1003816100381610038161003816119891 (119909)
1003816100381610038161003816le sum
119895isinZ
10038161003816100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816
le sum
119895isinZ
min(2minus119886119895sup119895isinZ
(2119886119895 10038161003816100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
2119895119887sup119895isinZ
(2minus119895119887 10038161003816
100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816))
(71)
We define119873(119909) as the largest index such that
2119895119887sup119895isinZ
(2minus119895119887 10038161003816
100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816) le 2
minus119886119895sup119895isinZ
(2119886119895 10038161003816100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816) (72)
and we write1003816100381610038161003816119891 (119909)
1003816100381610038161003816le sum
119895le119873(119909)
2119895119887sup119895isinZ
(2minus119895119887 10038161003816
100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
+ sum
119895gt119873(119909)
2minus119886119895sup
119895
(2119886119895 10038161003816100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
le 119862(sup119895isinZ
2119886119895 10038161003816100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
119887(119886+119887)
times (sup119895isinZ
2minus119887119895 10038161003816
100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
119886(119886+119887)
(73)
Thus (69) is proved In order to obtain (70) it is enough toapply the Holder inequality in the expression above since wehave 120579 = 119886(119886+119887) isin (0 1) and let 1119901 = (1minus120579)1199021+1205791199022
Corollary 24 Let 119902 isin (1infin) and let 119904 isin R such that 0 lt 119904 lt
(119889 + 2120573 + 2)119902 then one has
10038171003817100381710038171198911003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
10038171003817100381710038171198911003817100381710038171003817
1minus(119902119901)
Bminus((2120573+2+119889)119902minus119904)120573
infininfin (R119889+1
+ )
10038171003817100381710038171198911003817100381710038171003817
119902119901
B119904120573
119902119902(R119889+1
+ )
(74)
10038171003817100381710038171198911003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
10038171003817100381710038171198911003817100381710038171003817
1minus(119902119901)
Bminus((2120573+2+119889)119902minus119904)120573
infininfin (R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
119902119901
H119904119902120573(R119889+1+
) (75)
where 119901 = 119902(2120573 + 2 + 119889)(2120573 + 2 + 119889 minus 119902119904)
Proof By choosing 119886 = 119904 gt 0 minus119887 = 119904 minus (119889 + 2120573 + 2)119902 lt 01199021 = 119902 and 1199022 = infin we deduce (74) from the relations (70)and (67) In the same way we deduce (75) from the relations(70) and (68)
4 Generalized Heat Equation
41 Characterization for the Weinstein-Besov Spaces TheWeinstein heat equation reads
120597119905119906 (119905 119909) minus Δ 120573119906 (119905 119909) = 119891 (119905 119909) (119905 119909) isin [0infin) timesR119889+1
+
119906|119905=0 = 119892
(76)
We introduce the Weinstein heat semigroup 119867120573(119905) for theWeinstein-Laplace operator
119867120573 (119905) 119892 (119909) =
int
R119889+1+
Γ120573 (119905 119909 119910) 119892 (119910) 119889120583120573 (119910) if 119905 gt 0
119892 (119909) if 119905 = 0(77)
where Γ120573 is the Weinstein heat kernel defined by
Γ120573 (119905 119909 119910) = 120591119909 (119864(120573)
119905) (119910) (78)
where
119864(120573)
119905(119910) =
2
1205871198892Γ (120573 + 1) (4119905)
120573+1+1198892119890minus11991024119905 (79)
Thus
119867120573 (119905) 119892 (119909) = 119892lowast119882119864(120573)
119905 (119909) (80)
In practice we use the integral formulation of (76)
119906 (119905 119909) = 119867120573 (119905) 119892 (119909) + 119866120573 (119891) (119905 119909)
= 119867120573 (119905) 119892 (119909) + int
119905
0
119867120573 (119905 minus 119904) 119891 (119904 119909) 119889119904
(81)
Remark 25 The function 119864(120573)119905
is the Gauss kernel associatedwith Weinstein operators This function satisfies
forall120585 isin R119889+1
+ F119882 (119864
(120573)
119905) (120585) = 119890
minus1199051205852
(82)
Proposition 26 Let 1 le 119901 le 119903 le infin and let 119891 isin 119871119901
120573(R119889+1
+)
Then the operator 119867120573(119905) maps 119871119901
120573(R119889+1
+) continuously to
119871119903
120573(R119889+1
+) and
10038171003817100381710038171003817119867120573 (119905) 119891
10038171003817100381710038171003817119871119903120573(R119889)
le 119862119905minus((119889+2120573+2)2)(1119901minus1119903)1003817
1003817100381710038171198911003817100381710038171003817119871119901
120573(R119889)
(83)
Moreover1003817100381710038171003817100381710038171003817
(minusΔ 120573)
1205752
119867120573 (119905) 119891
1003817100381710038171003817100381710038171003817119871119903120573(R119889)
le 119862119905minus1205752minus((119889+2120573+2)2)(1119901minus1119903)1003817
1003817100381710038171198911003817100381710038171003817119871119901
120573(R119889)
(84)
for all 120575 gt 0
Proof It follows from the relations (80) and (29) combinedwith scaling property of the kernel 119864(120573)
119905
In this section we prove estimates for the Weinstein heatsemigroupThese estimates are based on the following result
Lemma 27 Let C be an annulus Positive constants 119888 and 119862exist such that for any 119901 in [1infin] and any couple (119905 120582) ofpositive real numbers one has
suppF119882 (119906) sub 120582C 997904rArr
10038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
le 119862119890minus1198881199051205822
119906119871119901
120573(R119889+1+
)
(85)
8 Journal of Function Spaces and Applications
Proof We again consider a function Θ in 119863(R119889+1
+ 0) the
value of which is identically 1 in neighborhood of annulusCWe can also assume without loss of generality that 120582 = 1 Wethen have
119867120573 (119905) 119906 = 119892 (119905 sdot) lowast119882119906 (86)where
119892 (119905 sdot) = Fminus1
119882(Θ (120585) 119890
minus1199051205852
) (87)
The lemma is proved provided that we can find positive realnumbers 119888 and 119862 such that
forall119905 gt 01003817100381710038171003817119892 (119905 sdot)
10038171003817100381710038171198711120573(R119889+1+
)le 119862119890
minus119888119905 (88)
To begin we perform integrations by parts in (87) We get1003816100381610038161003816119892 (119905 119909)
1003816100381610038161003816=
1
119888120573
(1 + 1199092)
minus(119889+[2120573]+3)
times int
R119889+1+
Λ (119909 120585) (119868119889 minus Δ 120573)
119889+[2120573]+3
times (Θ (120585) 119890minus1199051205852
) 119889120583120573 (120585)
(89)
Using Leibnizrsquos formula we obtain1003816100381610038161003816119892 (119905 119909)
1003816100381610038161003816le 119862(1 + 119909
2)
minus(119889+[2120573]+3)
119890minus119888119905 (90)
and (88) follows
For any interval 119868 of R (bounded or unbounded) wedefine themixed space-time 119871119901(119868 119871119902
120573(R119889+1
+)) Banach space of
(classes of) measurable functions 119906 119868 rarr 119871119902
120573(R119889+1
+) such
that 119906119871119901(119868119871
119902
120573(R119889+1+
))lt infin with
119906119871119901(119868119871119902
120573(R119889+1+
))= (int
119868
119906 (119905 sdot)119901
119871119902
120573(R119889+1+
)119889119905)
1119901
if 1 le 119901 119902 lt infin
119906119871infin(119868119871119902
120573(R119889+1+
))= ess sup
119905isin119868
119906 (119905 sdot)119871119902
120573(R119889+1+
) if 1 le 119902 lt infin
(91)Corollary 28 Let C be an annulus and 120582 a positive realnumber Let 1199060 (resp 119891 = 119891(119905 119909)) satisfy suppF119882(1199060) sub 120582C(resp suppF119882(119891(119905 sdot)) sub 120582C for all 119905 in [0 119879]) Consider 119906 asolution of
120597119905119906 minus Δ 120573119906 = 0 119906|119905=0 = 1199060 (92)and V a solution of
120597119905V minus Δ 120573V = 119891 (119905 sdot) V|119905=0 = 0 (93)There exist positive constants 119888 and 119862 depending only on Csuch that for any 1 le 119886 le 119887 le infin and 1 le 119901 le 119902 le infin we have
119906119871119902([0119879]119871119887120573(R119889+1+
))le 119862120582
(119889+2120573+2)(1119886minus1119887)120582minus21199021003817
1003817100381710038171199060
1003817100381710038171003817119871119886120573(R119889+1+
)
V119871119902([0119879]119871119887120573(R119889+1+
))le 119862120582
minus2(1+1119902minus1119901)120582(119889+2120573+2)(1119886minus1119887)
times10038171003817100381710038171198911003817100381710038171003817119871119901([0119879]119871119886
120573(R119889+1+
))
(94)
Proof It suffices to use the fact that
119906 (119905 sdot) = 119867120573 (119905) 1199060 V (119905 sdot) = int119905
0
119867120573 (119905 minus 119904) 119891 (119904 sdot) 119889119904
(95)
Combining Lemma 27 and Youngrsquos inequality (29) withscaling property of the kernel 119864(120573)
119905now yields the result
Theorem 29 Let 119904 be a positive real number and (119901 119903) isin
[1infin]2 A constant 119862 exists which satisfies the following
property For 119906 isin Bminus2119904120573
119901119903 (R119889+1
+) one has
119862minus1119906
Bminus2119904120573
119901119903(R119889+1+
)le
10038171003817100381710038171003817100381710038171003817
10038171003817100381710038171003817119905119904119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
10038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
le 119862119906Bminus2119904120573
119901119903(R119889+1+
)
(96)
To prove this result we need the following lemma
Lemma 30 There exist two positive constants 120581 and 119862
depending only on 120593 such that for all 1 le 119901 le infin 120591 ge 0 and119895 isin Z one has
10038171003817100381710038171003817Δ 119895 (119867120573 (120591) 119906)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862119890
minus1205812211989512059110038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
) (97)
Proof The result follows immediately by applying Lemma 27and because Δ 119895(119867120573(120591))119906 = (119867120573(120591)Δ 119895)119906
Proof of Theorem 29 Using Lemma 30 and considering thefact that the operator Δ 119895 commutes with the operator 119867120573(119905)
and the definition of the homogeneous Weinstein-Besov(semi) norm we get
10038171003817100381710038171003817119905119904119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862119906
Bminus2119904120573
119901119903(R119889+1+
)sum
119895isinZ
11990511990422119895119904119890minus12058111990522119895
119888119903119895
(98)
where (119888119903119895)119895isinZ denotes as in all this proof a generic elementof the unit sphere of 119897119903(Z) In the case when 119903 = infin therequired inequality comes immediately from the followingeasy result For any positive 119904 we have
sup119905gt0
sum
119895isinZ
11990511990422119895119904119890minus12058111990522119895
lt infin (99)
In the case 119903 lt infin using the Holder inequality with theweight 22119895119904119890minus1205811199052
2119895
(99) and the Fubini theorem we obtain
int
infin
0
11990511990311990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)
119889119905
119905
le 119862119906119903
Bminus2119904120573
119901119903(R119889+1+
)int
infin
0
(sum
119895isinZ
11990511990422119895119904119890minus12058111990522119895
)
119903minus1
times (sum
119895isinZ
11990511990422119895119904119890minus12058111990522119895
119888119903
119903119895)
119889119905
119905
Journal of Function Spaces and Applications 9
le 119862119906119903
Bminus2119904120573
119901119903(R119889+1+
)int
infin
0
(sum
119895isinZ
11990511990422119895119904119890minus12058111990522119895
119888119903
119903119895)
119889119905
119905
le 119862119906119903
Bminus2119904120573
119901119903(R119889+1+
)sum
119895isinZ
119888119903
119903119895int
infin
0
(11990511990422119895119904119890minus12058111990522119895
)
119889119905
119905
le 119862Γ (119904) 119906119903
Bminus2119904120573
119901119903(R119889+1+
)
(100)
In order to prove the other inequality let us observe thatfor any 119904 greater than minus1 we have
Δ 119895119906 =
1
Γ (119904 + 1)
int
infin
0
119905119904(minusΔ 120573)
119904+1
119867120573 (119905) Δ 119895119906 119889119905 (101)
Then Lemma 30 Proposition 9 and the fact that the operatorΔ 119895 commutes with the operator119867120573(119905) lead to the following
10038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862int
infin
0
11990511990422119895(119904+1)
119890minus1205811199052211989510038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889119905
(102)
In the case 119903 = infin we simply write
10038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862(sup
119905gt0
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
times int
infin
0
22119895(119904+1)
119890minus12058111990522119895
119889119905
le 11986222119895119904(sup119905gt0
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
(103)
In the case 119903 lt infin Holderrsquos inequality with the weight 119890minus12058111990522119895
gives
(int
infin
0
119905119904119890minus1205811199052211989510038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889119905)
119903
le 1198622minus2119895(119903minus1)
int
infin
0
119905119903119904119890minus1205811199052211989510038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)119889119905
(104)
Thanks to (99) and Fubinirsquos theorem we infer from (102) that
sum
119895isinZ
2minus211989511990311990410038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)le 119862int
infin
0
11990511990311990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)
119889119905
119905
(105)
The theorem is proved
Second Proof ofTheorem 29We only consider the case 1 le 119903 ltinfinThe case 119903 = infin can be shown similarlyWe first prove that
119862minus1119906
Bminus2119904120573
119901119903(R119889+1+
)le
10038171003817100381710038171003817100381710038171003817
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
10038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
(106)
It is easy to see that
Δ 119895119906 = 120594119895lowast119882119864(120573)
2minus2119895lowast119882119906
(107)
where 120594119895 = Fminus1
119882(120593(2
minus119895120585)119890
2minus21198951205852
) and119864(120573)2minus2119895
is the Gauss kernelassociated with Weinstein operators By relation (29) we get
10038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le
10038171003817100381710038171003817120594119895
100381710038171003817100381710038171198711120573(R119889+1+
)
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
) (108)
As10038171003817100381710038171003817120594119895
100381710038171003817100381710038171198711120573(R119889+1+
)= int
R119889+1+
100381610038161003816100381610038161003816F
minus1
119882(120593 (120585) 119890
1205852
)
100381610038161003816100381610038161003816119889120583120573 (120585) lt infin (109)
we obtain10038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
) (110)
Moreover simple calculations give that
119864(120573)
2minus2119895lowast119882119906 = 119867120573 (2
minus4119895minus 119905
2) (119864
(120573)
1199052lowast119882119906)
(111)
Thus from Proposition 26 it follows that100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
100381710038171003817100381710038171003817119864(120573)
1199052lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1
+ )
(112)
for any 119905 isin [2minus119895minus1 2minus119895] which implies that
sum
119895isinZ
2minus211990411989511990310038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)
le 119862 sum
119895isinZ
int
2minus119895
2minus119895minus1(119905
2119904100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903119889119905
119905
le 119862int
infin
0
(1199052119904100381710038171003817100381710038171003817119864(120573)
1199052lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903119889119905
119905
le 119862int
infin
0
(11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903119889119905
119905
(113)
where we have used the fact that 119864(120573)1199052lowast119882119906 = 119867120573(119905
2)119906
We now prove that10038171003817100381710038171003817100381710038171003817
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
10038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
le 119862119906Bminus2119904120573
119901119903(R119889+1+
) (114)
Indeed one has
119864(120573)
2minus2119895lowast119882119906 = sum
119899isinZ
119864(120573)
2minus2119895lowast119882Δ 119899+119895119906 (115)
Arguing as above we have100381710038171003817100381710038171003817119864(120573)
1199052lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1
+ )
(116)
for any 119905 isin [2minus119895 21minus119895] Thus10038171003817100381710038171003817100381710038171003817
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
10038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
= 2
100381710038171003817100381710038171003817100381710038171003817
1003817100381710038171003817100381710038171199052119904119864(120573)
1199052lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)
100381710038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
le 119862 sum
119895isinZ
int
21minus119895
2minus119895(2
minus2119895119904100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903119889119905
119905
le 119862 sum
119895isinZ
(2minus2119895119904
sum
119899isinZ
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
(117)
10 Journal of Function Spaces and Applications
On the other hand it is easy to see that100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)le 1198622
minus211989911990410038171003817100381710038171003817Δ 119899+119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
) (118)
for any 119904 gt 0 For 0 lt 1199041 lt 119904 lt 1199042 and by using theMinkowskiinequality we have
sum
119895isinZ
(2minus2119895119904
sum
119899isinZ
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
le sum
119895isinZ
(2minus2119895119904
0
sum
minusinfin
2minus21198991199041
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
+ sum
119895isinZ
(2minus2119895119904
sum
119899isinN
2minus21198991199042
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
le 119862(
0
sum
minusinfin
2minus2119899(119904
1minus119904)(sum
119895isinZ
(2minus2(119899+119895)11990311990410038171003817
100381710038171003817Δ 119899+119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
)
1119903
)
119903
+ 119862(sum
N
2minus2119899(119904
2minus119904)(sum
119895isinZ
(2minus2(119899+119895)11990311990410038171003817
100381710038171003817Δ 119899+119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
)
1119903
)
119903
le 119862 sum
119895isinZ
2minus211989511990311990410038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)
(119)
The result is immediately from (117) and (119)
42 Embedding Sobolev Theorems
Theorem 31 Let 1 lt 119901 lt infin and let 0 lt 119904 lt (119889 + 2120573 +
2)119901There exists a positive constant119862 such that for all function119891 isin
H119904
119901120573(R119889+1
+) one has
10038171003817100381710038171198911003817100381710038171003817119871119902
120573(R119889+1+
)le 119862
10038171003817100381710038171198911003817100381710038171003817
1minus120579
H119904119901120573(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
120579
B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
) (120)
where 120579 = 119904119901(119889+2120573+2) and 119902 = 119901(119889+2120573+2)(119889+2120573+2minus119901119904)
Proof Bydensity we can suppose that119891belongs toSlowast(R119889+1
)It is easy to see that
119891 = int
infin
0
119867120573 (119905) Δ 120573119891119889119905(121)
and decompose the integral in two parts as follows
119891 = int
119860
0
119867120573 (119905) Δ 120573119891119889119905 + int
infin
119860
119867120573 (119905) Δ 120573119891119889119905(122)
where 119860 is a constant to be fixed laterOn the other hand byTheorem 29 we obtain10038171003817100381710038171003817119867120573 (119905) Δ 120573119891
10038171003817100381710038171003817119871infin120573(R119889+1+
)
le
119862
1199051minus(12)(119904minus(119889+2120573+2)119901)
10038171003817100381710038171198911003817100381710038171003817B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
)
(123)
Therefore after integrating we get
int
infin
119860
10038171003817100381710038171003817119867120573 (119905) Δ 120573119891
10038171003817100381710038171003817119871infin120573(R119889+1+
)119889119905
le 119860(12)(119904minus(119889+2120573+2)119901)1003817
1003817100381710038171198911003817100381710038171003817B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
)
(124)
On the other hand denoting 119892 = (minusΔ 120573)1199042119891 we have
119867120573 (119905) Δ 120573119891 =
1
(minus119905)1minus1199042
119867120573 (119905) (minus119905Δ 120573)
1minus1199042
119892 (125)
We proceed as in [8] we prove that1003816100381610038161003816100381610038161003816
119867120573 (119905) (minus119905Δ 120573)
1minus1199042
119892 (119909)
1003816100381610038161003816100381610038161003816
le 119862 (119904)119872120573 (119892) (119909) (126)
where119872120573(119892) is a maximal function of 119892 associated with theWeinstein operators (cf [12])
This leads to100381610038161003816100381610038161003816100381610038161003816
int
119860
0
119867120573 (119905) Δ 120573119891 (119909) 119889119905
100381610038161003816100381610038161003816100381610038161003816
le 1198621198601199042119872120573 (119892) (119909) (127)
In conclusion we get10038161003816100381610038161003816100381610038161003816
int
infin
0
119867120573 (119905) Δ 120573119891 (119909) 119889119905
10038161003816100381610038161003816100381610038161003816
le 119862 (1198601199042119872120573 (119892) (119909)
+119860(12)(119904minus(119889+2120573+2)119901)1003817
1003817100381710038171198911003817100381710038171003817B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
))
(128)
and the choice of 119860 such that
119860(119889+2120573+2)2119901
119872120573 (119892) (119909) =10038171003817100381710038171198911003817100381710038171003817B119904minus(119889+2120573+2)119901120573
infininfin (R119889+1+
)(129)
ensures that10038161003816100381610038161003816100381610038161003816
int
infin
0
119867120573 (119905) Δ 120573119891 (119909) 119889119905
10038161003816100381610038161003816100381610038161003816
le 119862(119872120573(119892)(119909))
1minus(119901119904(119889+2120573+2))10038171003817100381710038171198911003817100381710038171003817
119901119904(119889+2120573+2)
B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
)
(130)
Finally taking the 119871119902120573norm with 119902 = 119901(119889 + 2120573 + 2)(119889 + 2120573 +
2minus119901119904) ends the proof thanks to the fact themaximal function119872120573 is bounded of 119871119902
120573(R119889+1
+) into itself for 119902 gt 1
Theorem 32 Let 1 lt 119901 lt 119902 lt infin For all function 119891 such that119891 isin
H1199041
119901120573(R119889+1
+)⋂
Bminus120573120573
infininfin(R119889+1
+) one has
10038171003817100381710038171198911003817100381710038171003817H119904119901120573(R119889+1+
)le 119862
10038171003817100381710038171198911003817100381710038171003817
120579
H1199041
119901120573(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
1minus120579
Bminus120573120573
infininfin(R119889+1
+) (131)
where 120579 = 119901119902 119904 = 1205791199041 minus (1 minus 120579)120573 with 120573 gt 0 minus120573 lt 119904 lt 1199041
Proof It suffices to prove that1003817100381710038171003817100381710038171003817
(minusΔ 120573)
(119904minus1199041)2
119891
1003817100381710038171003817100381710038171003817119871119902
120573(R119889+1+
)
le 11986210038171003817100381710038171198911003817100381710038171003817
120579
119871119901
120573(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
1minus120579
Bminus120573minus1199041120573
infininfin (R119889+1+
)
(132)
Journal of Function Spaces and Applications 11
Indeed we use the following identity (which may be easilyproven by taking the Weinstein transform in 119909 of both sides)
(minusΔ 120573)
minus1205752
119891 (119909) =
1
Γ (1205752)
int
infin
0
1199051205752minus1
119867120573 (119905) 119891 (119909) 119889119905 (133)
with 120575 = 1199041 minus 119904 gt 0We decompose the integral in two parts as follows
(minusΔ 120573)
minus1205752
119891 (119909) =
1
Γ (1205752)
int
119879
0
1199051205752minus1
119867120573 (119905) 119891 (119909) 119889119905
+
1
Γ (1205752)
int
infin
119879
1199051205752minus1
119867120573 (119905) 119891 (119909) 119889119905
(134)
where 119879 is a constant to be fixed laterWe proceed as in [8] we obtain
10038161003816100381610038161003816119867120573 (119905) 119891 (119909)
10038161003816100381610038161003816le 119862119872120573 (119891) (119909) (135)
On the other hand we use Theorem 29 and the fact that 119891belongs to Bminus120573minus119904
1120573
infininfin(R119889+1
+) to deduce that
10038161003816100381610038161003816119867120573 (119905) 119891 (119909)
10038161003816100381610038161003816le 119862119905
(minus120573minus1199041)210038171003817100381710038171198911003817100381710038171003817Bminus120573minus1199041120573
infininfin (R119889+1+
) (136)
Thus by applying the preceding estimates on the right part of(134) we obtain
1003816100381610038161003816100381610038161003816
(minusΔ 120573)
minus1205752
119891 (119909)
1003816100381610038161003816100381610038161003816
le
1198621
Γ (1205752)
1198791205752119872120573 (119891) (119909)
+
1198622
Γ (1205752)
119879(120575minus120573minus119904
1)210038171003817100381710038171198911003817100381710038171003817Bminus120573minus1199041120573
infininfin (R119889+1+
)
(137)
We fix now
119879 = (
10038171003817100381710038171198911003817100381710038171003817Bminus120573minus1199041120573
infininfin (R119889+1+
)
119872120573 (119891) (119909)
)
2(120573+1199041)
(138)
We obtain
1003816100381610038161003816100381610038161003816
(minusΔ120573)
minus1205752
119891 (119909)
1003816100381610038161003816100381610038161003816
le
1198621 + 1198622
Γ (1205752)
(119872120573(119891)(119909))
12057910038171003817100381710038171198911003817100381710038171003817
1minus120579
Bminus120573minus1199041120573
infininfin (R119889+1+
)
(139)
Thus we deduce that1003817100381710038171003817100381710038171003817
(minusΔ120573)
minus1205752
119891
1003817100381710038171003817100381710038171003817119871119902
120573(R119889+1+
)
le
1198621 + 1198622
Γ (1205752)
10038171003817100381710038171003817119872120573 (119891)
10038171003817100381710038171003817
120579
119871119901
120573(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
1minus120579
Bminus120573minus1199041120573
infininfin (R119889+1+
)
(140)
To conclude we used the fact that the maximal function119872120573
is bounded of 119871119902120573(R119889+1
+) into itself for 119902 gt 1
43 Estimates in Generalized Besov Spaces For any interval 119868ofR (bounded or unbounded) and a normed space 119865(R119889+1
+)
we define the mixed space-time 119871119901(119868 119865(R119889+1
+)) space of
(classes of) measurable functions 119906 119868 rarr 119865(R119889+1
+) such that
||119906||119871119901(119868119865(R119889+1+
)) lt infin with
119906119871119901(119868119865(R119889+1+
)) = (int
119868
119906 (119905 sdot)119901
119865(R119889+1+
)119889119905)
1119901
if 1 le 119901 lt infin
119906119871infin(119868119865(R119889+1+
)) = ess sup119905isin119868
119906 (119905 sdot)119865(R119889+1+
)
(141)
For any interval 119868 of R (bounded or unbounded) anda Banach space 119883 we define the mixed space-time 119862(119868119883)space of continuous functions 119868 rarr 119883 When 119868 is bounded119862(119868119883) is a Banach space with the norm of 119871infin(119868 119883)
Theorem 33 Let 119904 isin R and 1 le 119901 119902 119903 le infin Let 119879 gt 0 119892 isin
B119904120573
119901119903(R119889+1
+) and119891 in 119871119902((0 119879) B
119904minus2+(2119902)120573
119901119903 (R119889+1
+)) Then (76)
has a unique solution
119906 isin 119871119902((0 119879)
B119904+(2119902)120573
119901119903(R
119889+1
+))
⋂119871infin((0 119879)
B119904120573
119901119903(R
119889+1
+))
(142)
and there exists a constant 119862 such that for all 1199021 isin [119902infin] onehas
1199061198711199021 ((0119879)B
119904+(21199021)120573
119901119903(R119889+1+
))
le 119862(10038171003817100381710038171198921003817100381710038171003817B119904120573
119901119903(R119889+1+
)+10038171003817100381710038171198911003817100381710038171003817119871119902((0119879)B
119904minus2+(2119902)120573
119901119903(R119889+1+
)))
(143)
If in addition 119903 lt infin then 119906 isin 119862([0 119879] B119904120573
119901119903(R119889+1
+))
Proof Since 119892 and 119891 are temperate distributions (76) has aunique solution 119906 in S1015840
((0 119879) timesR119889+1
+) which satisfies
F119882 (119906) (119905 120585) = 119890minus1199051205852
F119882 (119892) (120585)
+ int
119905
0
119890(120591minus119905)120585
2
F119882 (119891) (120591 120585) 119889120591
(144)
Next we notice that applying Δ 119895 to (76) and using formula(81) yield
Δ 119895119906 (119905 sdot) = 119867120573 (119905) Δ 119895119892 + int
119905
0
119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot) 119889120591(145)
Therefore
10038171003817100381710038171003817Δ 119895119906 (119905 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le
10038171003817100381710038171003817119867120573(119905)Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+ int
119905
0
10038171003817100381710038171003817119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591
(146)
12 Journal of Function Spaces and Applications
By virtue of Lemma 30 we thus have for some 120581 gt 0
10038171003817100381710038171003817Δ 119895119906(119905 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
le 119862[119890minus1205812211989511990510038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+ int
119905
0
119890minus12058122119895(119905minus120591) 10038171003817
100381710038171003817Δ 119895119891 (120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591]
(147)
Applying convolution inequalities we get
10038171003817100381710038171003817Δ 119895119906
100381710038171003817100381710038171198711199021 ((0119879)119871
119901
120573(R119889+1+
))
le 119862[
[
((
1 minus 119890minus120581119879119902122119895
120581119902122119895
)
11199021
)
10038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+((
1 minus 119890minus120581119879119902222119895
120581119902222119895
)
11199022
)
10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119902((0119879)119871
119901
120573(R119889+1+
))
]
]
(148)
with 11199022 = 1+ 11199021 minus1119902 Finally taking the 119897119903(Z) norm we
conclude that (with the usual convention if 119903 = infin)
1199061198711199021 ((0119879)B
119904+(21199021)120573
119901119903(R119889+1+
))
le 119862[
[
sum
119895isinZ
((
1 minus 119890minus120581119879119902122119895
120581119902122119895
)
1199031199021
)(211989511990410038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
]
]
1119903
+ 119862[
[
sum
119895isinZ
((
1 minus 119890minus120581119879119902222119895
120581119902222119895
)
1199031199022
)
times (2119895(119904minus2+2119902)10038171003817
100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119902(0119879119871
119901
120573(R119889+1+
))
119903
]
]
1119903
(149)
which insures that 119906 isin 119871119902((0 119879)
B119904+(2119902)120573
119901119903 (R119889+1
+))
⋂119871infin((0 119879)
B119904120573
119901119903(R119889+1
+)) and yields the desired inequality
Since 119906 belongs to 119862([0 119879]B119904120573
119901119903(R119889+1
+)) in the case where
119903 is finite may be easily deduced from the density ofSlowast(R
119889+1)⋂
B119904120573
119901119903(R119889+1
+) in B
119904120573
119901119903(R)
Theorem 34 Let 119904 isin R 119879 gt 0 and 1 le 119901 119902 119903 le infinOne supposes that 119892 isin 119861
119904120573
119901119903(R119889+1
+) and 119891 isin 119871
119902((0 119879)
119861119904minus2+(2119902)120573
119901119903 (R119889+1
+)) Then (76) has a unique solution 119906 belong-
ing to
119871119902((0 119879) 119861
119904+(2119902)120573
119901119903(R
119889+1
+))⋂119871
infin((0 119879) 119861
119904120573
119901119903(R
119889+1
+))
(150)
and there exists a constant 119862 such that for all 119902 le 1199021 le infin
1199061198711199021 ((0119879)119861
119904+(21199021)120573
119901119903(R119889+1+
))
le 119862 [ (1 + 11987911199021)10038171003817100381710038171198921003817100381710038171003817119861119904120573
119901119903(R119889+1+
)
+ (1 + 1198791+1119902
1minus1119902
)10038171003817100381710038171198911003817100381710038171003817119871119902((0119879)119861
119904minus2+(2119902)120573
119901119903(R119889+1+
))]
(151)
If in addition 119903 lt infin then 119906 isin 119862([0 119879] 119861119904120573119901119903(R119889+1
+))
Proof Since 119892 119891 are tempered (76) has a unique solution 119906in S1015840
((0 119879) timesR119889+1
+) satisfying
F119882 (119906) (119905 120585) = 119890minus1199051205852
F119882 (119892) (120585)
+ int
119905
0
119890(120591minus119905)120585
2
F119882 (119891) (120591 120585) 119889120591
(152)
Hence applying Δ 119895 119895 ge 0 to (81) we see that
Δ 119895119906 (119905 sdot) = 119867120573 (119905) Δ 119895119892 + int
119905
0
119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot) 119889120591(153)
and thus by Lemma 30 we can deduce that10038171003817100381710038171003817Δ 119895119906 (119905 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
le
10038171003817100381710038171003817119867120573(119905)Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)+ int
119905
0
10038171003817100381710038171003817119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591
le 119862[119890minus1205812211989511990510038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+int
119905
0
119890minus12058122119895(119905minus120591)10038171003817
100381710038171003817Δ 119895119891(120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591]
(154)
Then it follows from convolution inequalities thatΔ 1198951199061198711199021 ((0119879)119871
119901
120573(R119889+1+
))is dominated by
(
1 minus 119890minus120581119879119902122119895
120581119902122119895
)
11199021
10038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119861119904120573
119901119903(R119889+1+
)
+ (
1 minus 119890minus120581119879119902222119895
120581119902222119895
)
11199022
10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119902((0119879)119871
119901
120573(R119889+1+
))
(155)
with 11199022 = 1 + 11199021 minus 1119902 Moreover similarly as above wecan obtain that
1003817100381710038171003817Δminus1119906(119905 sdot)
1003817100381710038171003817119871119901
120573(R119889+1+
)le1003817100381710038171003817Δminus1119892
1003817100381710038171003817119871119901
120573(R119889+1+
)
+ int
119905
0
1003817100381710038171003817Δminus1119891 (120591 sdot)
1003817100381710038171003817119871119901
120573(R119889+1+
)119889120591
(156)
and thus if 1 le 119902 le 1199021 le infin1003817100381710038171003817Δminus1119906
10038171003817100381710038171198711199021 ((0119879)119871
119901
120573(R119889+1+
))
le 119862(119879111990211003817100381710038171003817Δminus1119892
1003817100381710038171003817119871119901
120573(R119889+1+
)+ 119879
111990221003817100381710038171003817Δminus1119891
1003817100381710038171003817119871119902((0119879)119871
119901
120573(R119889+1+
)))
(157)
Journal of Function Spaces and Applications 13
Finally taking the 119897119903-normwith respect to 119895 in (155) and (157)with the usual convention if 119903 = infin we can deduce the desiredestimate
Acknowledgment
Theauthor gratefully acknowledges theDeanship of ScientificResearch at the University of Taibah The author is deeplyindebted to the referee for providing constructive commentsand help in improving the contents of this paper
References
[1] Z Ben Nahia and N Ben Salem ldquoSpherical harmonics andapplications associated with the Weinstein operatorrdquo in Pro-ceedings of the International Conference on PotentialTheory heldin Kouty Czech Republic (ICPT rsquo94) pp 235ndash241 1996
[2] Z Ben Nahia and N Ben Salem ldquoOn a mean value propertyassociated with the Weinstein operatorrdquo in Proceedings of theInternational Conference on Potential Theory held in KoutyCzech Republic (ICPT rsquo94) pp 243ndash253 1996
[3] M Brelot ldquoEquation de Weinstein et potentiels de MarcelRieszrdquo in Seminaire de Theorie de Potentiel Paris No 3 vol 681of Lecture Notes in Mathematics pp 18ndash38 Springer BerlinGermany 1978
[4] H Mejjaoli and M Salhi ldquoUncertainty principles for theweinstein transformrdquo Czechoslovak Mathematical Journal vol61 no 4 pp 941ndash974 2011
[5] H Mejjaoli and A Ould Ahmed Salem ldquoWeinstein Gabortransform and applicationsrdquo Advanced Studies in Pure Mathe-matics vol 2 no 3 pp 203ndash210 2012
[6] H Mejjaoli ldquoBesov spaces associated withthe Weinstein opera-tor and applicationsrdquo In press
[7] T Kawazoe and H Mejjaoli ldquoGeneralized Besov spaces andtheir applicationsrdquo Tokyo Journal of Mathematics vol 35 no 2pp 297ndash320 2012
[8] H Mejjaoli ldquoLittlewood-Paley decomposition associated withthe Dunkl operators and paraproduct operatorsrdquo Journal ofInequalities in Pure and Applied Mathematics vol 9 no 4 pp1ndash25 2008
[9] H Mejjaoli and N Sraeib ldquoGeneralized sobolev spaces inquantum calculus and applicationsrdquo Journal of Inequalities andSpecial Functions vol 1 no 4 pp 43ndash64 2012
[10] H Mejjaoli ldquoGeneralized homogeneous Besov spaces and theirapplicationsrdquo Serdica Mathematical Journal vol 38 no 4 pp575ndash614 2012
[11] H Triebel Interpolation Theory Functions Spaces DifferentialOperators North-Holland AmsterdamThe Netherlands 1978
[12] V S Guliev ldquoOn maximal function and fractional integralassociated with the Bessel differential operatorrdquo MathematicalInequalities and Applications vol 6 no 2 pp 317ndash330 2003
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Function Spaces
Abstract and Applied AnalysisHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
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Algebra
Discrete Dynamics in Nature and Society
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Decision SciencesAdvances in
Discrete MathematicsJournal of
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Volume 2014 Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Stochastic AnalysisInternational Journal of
4 Journal of Function Spaces and Applications
Proposition 5 Let 119891 be in 119871119901
120573(R119889+1
+) 1 le 119901 le infin and 120601
in Slowast(R119889+1
) Then the distribution T119891lowast119882120601 is given by thefunction 119891lowast119882120601 and T119891lowast119882120601 belongs to 119871119901
120573(R119889+1
+) Moreover
for all 120595 isin Slowast(R119889+1
)
⟨T119891lowast119882120601 120595⟩ = ⟨
119891 120601lowast119882 ⟩120573 (34)
where (119909) = 120595(minus119909) and
F119882 (T119891lowast119882 120601) = F119882 (T119891)F119882 (120601) (35)
For each 119906 isin S1015840
lowast(R119889+1
) we define the distribution Δ 120573119906
by ⟨Δ 120573119906 120595⟩ = ⟨119906 Δ 120573120595⟩ and this distribution satisfies thefollowing property
F119882 (Δ 120573119906) = minus10038171003817100381710038171199101003817100381710038171003817
2F119882 (119906) (36)
In the following we denote T119891 given by (30) by 119891 forsimplicity
3 B119904120573
119901119902 F119904120573
119901119902(R119889+1
+) H119904
119901120573Spaces and
Basic Properties
31 HomogeneousWeinstein-Littlewood-Paley DecompositionOne of the main tools in this paper is the homogeneousLittlewood-Paley decomposition of distribution associatedwith theWeinstein operators into dyadic blocs of frequencies
Lemma6 One defines byC the ring of center 0 of small radius12 and great radius 2 There exists two radial functions 120595 and120593 the values of which are in the interval [0 1] belonging to119863lowast(R
119889+1) such that
supp120595 sub 119861 (0 1) supp120593 sub C
forall120585 isin R119889+1
120595 (120585) + sum
119895ge0
120593 (2minus119895120585) = 1
forall120585 isin C sum
119895isinZ
120593 (2minus119895120585) = 1
|119899 minus 119898| ge 2 997904rArr supp120593 (2minus119899sdot) cap supp120593 (2minus119898sdot) = 0
119895 ge 1 997904rArr supp120595 cap supp120593 (2minus119895sdot) = 0
(37)
Notations We denote by
Δ 119895119891 = Fminus1
119882(120593(
120585
2119895)F119882 (119891))
119878119895119891 = sum
119899le119895minus1
Δ 119899119891 forall119895 isin Z(38)
The distribution Δ 119895119891 is called the 119895th dyadic block of thehomogeneous Littlewood-Paley decomposition of 119891 associ-ated with the Weinstein operators
Throughout this paper we define 120601 and 120594 by 120601 = Fminus1
119882(120593)
and 120594 = Fminus1
119882(120595)
When dealing with the Littlewood-Paley decompositionit is convenient to introduce the functions and 120593 belongingto119863lowast(R
119889+1) such that equiv 1 on supp120595 and 120593 equiv 1 on supp120593
Remark 7 We remark that
F119882 (119878119895119891) (120585) = (
120585
2119895)F119882 (119878119895119891) (120585)
F119882 (Δ 119895119891) (120585) = 120593(
120585
2119895)F119882 (Δ 119895119891) (120585)
(39)
We put
120601 = F
minus1
119882(120593) 120594 = F
minus1
119882() (40)
Definition 8 One denotes by S1015840
ℎ120573lowast(R119889+1
) the space oftempered distribution such that
lim119895rarrminusinfin
119878119895119906 = 0 in S1015840
lowast(R
119889+1) (41)
Proposition 9 (Bernstein inequalities) For all 120583 isin N119889+1 and120590 isin R for all 119895 isin Z for all 1 le 119901 119902 le infin and for all119891 isin S1015840
lowast(R119889+1
) one has the following
(i) 10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119902
120573(R119889+1+
)
le
10038171003817100381710038171003817
120601
10038171003817100381710038171003817119871119903120573(R119889+1+
)
10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119901
120573(R119889+1+
)2119895(119889+2120573+2)(1119901minus1119902)
with 1
119902
=
1
119901
+
1
119903
minus 1
(ii) 10038171003817100381710038171003817119878119895119891
10038171003817100381710038171003817119871119902
120573(R119889+1+
)
le10038171003817100381710038171205941003817100381710038171003817119871119903120573(R119889+1+
)
10038171003817100381710038171003817119878119895119891
10038171003817100381710038171003817119871119901
120573(R119889+1+
)2119895(119889+2120573+2)(1119901minus1119902)
with 1
119902
=
1
119901
+
1
119903
minus 1
(iii)1003817100381710038171003817100381710038171003817
(radicminusΔ 120573)
120590
Δ 119895119891
1003817100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)
le
10038171003817100381710038171003817F
minus1
119882(10038171003817100381710038171205851003817100381710038171003817
120590120593)
100381710038171003817100381710038171198711120573(R119889+1+
)
times
10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119901
120573(R119889+1+
)2119895120590
(42)
Proof Using Remark 7 we deduce from Proposition 5 that
119878119895119891 = 2119895(119889+2120573+2)
120594 (2119895sdot) lowast119882119878119895119891
Δ 119895119891 = 2119895(119889+2120573+2)
120601 (2119895sdot) lowast119882Δ 119895119891
(43)
Thus from the relation (29) we prove (i) (ii) and (iii)
32 Definitions In the following we define analogues of thehomogeneous Besov Triebel-Lizorkin and Riesz potentialspaces associated with the Weinstein operators on R119889+1
+and
obtain their basic propertiesFrom now we make the convention that for all non-
negative sequence 119886119902119902isinZ the notation (sum119902119886119903
119902)1119903 stands for
sup119902119886119902 in the case 119903 = infin
Journal of Function Spaces and Applications 5
Definition 10 Let 119904 isin R and 119901 119902 isin [1infin]The homogeneousWeinstein-Besov spaces B
119904120573
119901119902(R119889+1
+) are the spaces of distri-
bution in S1015840
ℎ120573lowast(R119889+1
) such that
10038171003817100381710038171198911003817100381710038171003817B119904120573
119901119902(R119889+1+
)= (sum
119895isinZ
(211990411989510038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119902
)
1119902
lt infin (44)
Proposition 11 (see [6]) Let 119904 isin R and 119901 and 119902 two elementsof [1infin] the space B
119904120573
119901119902(R119889+1
+) is the set of 119891 isin S1015840
ℎ120573lowast(R119889+1
)
verifying
10038171003817100381710038171003817
119891
10038171003817100381710038171003817B119904120573
119901119902(R119889+1+
)= (int
infin
0
(119905minus1199041003817100381710038171003817119891lowast119882120601119905
1003817100381710038171003817119871119901
120573(R119889+1+
))
119902119889119905
119905
)
1119902
lt infin
(45)
where 120601119905(119909) = (11199052120573+2+119889
)120601(119909119905) for all 119905 isin (0infin) and 119909 isin
R119889+1
+
Definition 12 For 119904 isin R and 119901 119902 isin [1infin] one writes10038171003817100381710038171198911003817100381710038171003817119861119904120573
119901119902(R119889+1+
)=10038171003817100381710038171198780119891
1003817100381710038171003817119871119901
120573(R119889+1+
)
+ (sum
119895ge1
(211990411989510038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119902
)
1119902
(46)
The nonhomogeneous Besov space 119861119904120573119901119902(R119889+1
+) associated
with the Weinstein operators is defined by
119861119904120573
119901119902(R
119889+1
+) = 119891 isin S
1015840(R
119889)
10038171003817100381710038171198911003817100381710038171003817119861119904120573
119901119902(R119889+1+
)lt infin (47)
We give now another definition equivalent to the nonho-mogeneous Besov space 119861119904120573119901119902(R119889+1
+)
Proposition 13 Let 119904 isin R and119901 and 119902 two elements of [1infin]the space 119861119904120573119901119902(R119889+1
+) is the set of 119891 isin S1015840
(R119889) verifying
10038171003817100381710038171003817
119891
10038171003817100381710038171003817119861119904120573
119901119902(R119889+1+
)=1003817100381710038171003817119891lowast119882120595
1003817100381710038171003817119871119901
120573(R119889+1+
)
+ (int
1
0
(119905minus1199041003817100381710038171003817119891lowast119882120601119905
1003817100381710038171003817119871119901
120573(R119889+1+
))
119902119889119905
119905
)
1119902
lt infin
(48)
Definition 14 Let 119904 isin R and 1 le 119901 119902 le infin the homogeneousWeinstein-Triebel-Lizorkin space F
119904120573
119901119902(R119889+1
+) is the space of
distribution in S1015840
ℎ120573lowast(R119889+1
) such that
10038171003817100381710038171198911003817100381710038171003817F119904120573
119901119902(R119889+1+
)=
100381710038171003817100381710038171003817100381710038171003817100381710038171003817
(sum
119895isinZ
211990411989511990210038161003816100381610038161003816Δ 119895119891
10038161003816100381610038161003816
119902
)
1119902100381710038171003817100381710038171003817100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)
lt infin (49)
Definition 15 For 119904 isin R the operatorR119904
120573from S1015840
ℎ120573lowast(R119889+1
)
to S1015840
ℎ120573lowast(R119889+1
) is defined by
R119904
120573(119891) = F
minus1
119882(sdot
119904F119882119891) (50)
The operatorRminus119904
120573is called Weinstein-Riesz potential space
Definition 16 For 119904 isin R and 1 le 119901 le infin the homogeneousWeinstein-Riesz potential space H119904
119901120573(R119889+1
+) is defined
as the space Rminus119904
120573(119871
119901
120573(R119889+1
+)) equipped with the norm
119891H119904119901120573(R119889+1+
)= R119904
120573(119891)
119871119901
120573(R119889+1+
)
Proposition 17 Let 119904 isin R and 1 le 119901 119902 le infinThe operator Δ 120573 is a linear continuous operator from
B119904120573
119901119902(R119889+1
+) into B
119904minus2120573
119901119902 (R119889+1
+) and from H119904
119901120573(R119889+1
+) into
H119904minus2
119901120573(R119889+1
+)
Proof We obtain these results by the similar ideas used in thenonhomogeneous case (cf [6])
Proposition 18 Let 119904 119905 isin R and 1 le 119901 119902 le infin The operatorR119905
120573is a linear continuous injective operator from B
119904120573
119901119902(R119889+1
+)
onto B119904minus119905120573
119901119902 (R119889+1
+) and from H119904
119901120573(R119889+1
+) onto H119904minus119905
119901120573(R119889+1
+)
Proof We obtain these results by the similar ideas used in thenonhomogeneous case (cf [6])
33 Embeddings As in the Euclidean case (cf [11]) themono-tone character of 119897119902-spaces and the Minkowskis inequalityyield the following
Proposition 19 If 1 le 1199021 lt 1199022 le infin one has
B119904120573
1199011199021
(R119889+1
+) 997893rarr
B119904120573
1199011199022
(R119889+1
+) (1 le 119901 le infin 119904 isin R)
(51)
MoreoverB119904120573
1199011(R
119889+1
+) 997893rarr
H119904
119901120573(R
119889+1
+) 997893rarr
B119904120573
119901infin(R
119889+1
+)
(1 le 119901 le infin 119904 isin R)
(52)
If 1199040 = 1199041 one also has
(H1199040
119901120573(R
119889+1
+)
H1199041
119901120573(R
119889+1
+))
120579119902=
B119904120573
119901119902(R
119889+1
+)
(1 le 119901 119902 le infin 120579 isin (0 1))
(53)
where 119904 = (1 minus 120579)1199040 + 1205791199041
Proposition 20 One assumes that 119904 minus (119889 + 2120573 + 2)119901 = 1199041 minus
(119889 + 2120573 + 2)1199011 Then the following inclusion holds
B119904120573
119901119902(R
119889+1
+) 997893rarr
B1199041120573
11990111199021
(R119889+1
+)
(1 le 119901 le 1199011 le infin 1 le 119902 le 1199021 le infin 119904 1199041 isin R)
(54)
Proof In order to prove the inclusion we use the estimate
Δ 119895119891 = 2119895(119889+2120573+2)
120601 (2119895sdot) lowast119882Δ 119895119891 (55)
Proposition 9(i) gives that10038171003817100381710038171003817Δ 119895119891
100381710038171003817100381710038171198711199011
120573(R119889+1+
)=
100381710038171003817100381710038172119895(119889+2120573+2)
120601 (2119895sdot) lowast119882Δ 119895119891
100381710038171003817100381710038171198711199011
120573(R119889+1+
)
le 1198622119895(119889+2120573+2)(1119901minus1119901
1)10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
(56)
6 Journal of Function Spaces and Applications
By definition of the homogeneous Weinstein-Besov spaceswe therefore infer10038171003817100381710038171198911003817100381710038171003817B1199041120573
11990111199021(R119889+1+
)
= (
infin
sum
119895=minusinfin
(2119895119904110038171003817100381710038171003817Δ 119895119891
100381710038171003817100381710038171198711199011
120573(R119889+1+
))
1199021
)
11199021
le 119862(sum
119895isinZ
(211989511990412119895(119889+2120573+2)(1119901minus1119901
1)10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
1199021
)
11199021
le 119862(sum
119895isinZ
(211989511990410038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
1199021
)
11199021
le 11986210038171003817100381710038171198911003817100381710038171003817B119904120573
119901119902(R119889+1+
)
(57)
since 119902 le 1199021 This gives the inclusion
Proposition 21 (1) If 119906 belongs to B119904120573
119901119902(R119889+1
+) cap
B119905120573
119901119902(R119889+1
+)
then 119906 belongs to B120579119904+(1minus120579)119905120573
119901119902 (R119889+1
+) for all 120579 isin [0 1] and
119906B120579119904+(1minus120579)119905120573
119901119902(R119889+1+
)le 119906
120579
B119904120573
119901119902(R119889+1+
)119906
1minus120579
B119905120573
119901119902(R119889+1+
) (58)
(2) If 119906 belongs to B119904120573
119901infin(R119889+1
+) cap
B119905120573
119901infin(R119889+1
+) and 119904 lt 119905
then 119906 belongs to B120579119904+(1minus120579)119905120573
1199011(R119889+1
+) for all 120579 isin (0 1) and there
exists a positive constant 119862(119905 119904) such that
119906B120579119904+(1minus120579)119905120573
1199011(R119889+1+
)le 119862 (119905 119904) 119906
120579
B119904120573
119901infin(R119889+1+
)119906
1minus120579
B119905120573
119901infin(R119889+1+
) (59)
(3) If 119906 belongs to B119904120573
119901infin(R119889+1
+) cap
B119904+120576120573
119901infin (R119889+1
+) and 120576 gt
0 then 119906 belongs to B119904120573
1199011(R119889+1
+) and there exists a positive
constant 119862 such that
119906B119904120573
1199011(R119889+1+
)le
119862
120576
119906B119904120573
119901infin(R119889+1+
)log
2(119890 +
119906B119904+120576120573
119901infin(R119889+1+
)
119906B119904120573
119901infin(R119889+1+
)
)
(60)
Proof (1) is obvious from the Holderrsquos inequality As for (2)we write 119906
B120579119904+(1minus120579)119905120573
1199011(R119889+1+
)as
sum
119895le119873
2119895(120579119904+(1minus120579)119905)10038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)+ sum
119895gt119873
2119895(120579119904+(1minus120579)119905)10038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
(61)
where 119873 is chosen here after By the definition of thehomogeneous Weinstein-Besov norms we see that
2119895(120579119904+(1minus120579)119905)10038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 2
119895(1minus120579)(119905minus119904)119906
B119904120573
119901infin(R119889+1+
)
2119895(120579119904+(1minus120579)119905)10038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 2
minus119895120579(119905minus119904)119906
B119905120573
119901infin(R119889+1+
)
(62)
and thus 119906B120579119904+(1minus120579)119905120573
1199011(R119889+1+
)is dominated by
119906B119904120573
119901infin(R119889+1+
)sum
119895le119873
2119895(1minus120579)(119905minus119904)
+ 119906B119905120573
119901infin(R119889+1+
)sum
119895gt119873
2minus119895120579(119905minus119904)
le 119862119906B119904120573
119901infin(R119889+1+
)
2(119873+1)(1minus120579)(119905minus119904)
2(1minus120579)(119905minus119904)
minus 1
+ 119906B119905120573
119901infin(R119889+1+
)
2minus119873120579(119905minus119904)
1 minus 2minus120579(119905minus119904)
(63)
Hence in order to complete the proof of (2) it suffices tochoose119873 such that
119906B119905120573
119901infin(R119889)
119906B119904120573
119901infin(R119889)
le 2119873(119905minus119904)
lt 2
119906B119905120573
119901infin(R119889)
119906B119904120573
119901infin(R119889)
(64)
As for (3) it is easy to see that 119906B119904120573
1199011(R119889+1+
)is dominated as
sum
119895le119873minus1
211989511990410038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)+ sum
119895ge119873
211989511990410038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
le (119873 + 1) 119906B119904120573
119901infin(R119889+1+
)+
2minus(119873minus1)120576
2120576minus 1
119906B119904+120576120573
119901infin(R119889+1+
)
(65)
Hence letting
119873 = 1 + [
[
1
120576
log2
119906B119904+120576120573
119901infin(R119889+1+
)
119906B119904120573
119901infin(R119889+1+
)
]
]
(66)
we can obtain the desired estimate
Proposition 22 Let 119902 isin (1infin) and let 119904 isin R such that0 lt 119904 lt (119889 + 2120573 + 2)119902 then one has
B119904120573
119902119902(R
119889+1
+) =
F119904120573
119902119902(R
119889+1
+) 997893rarr
F119904120573
119902infin(R
119889+1
+)
997893rarrF119904minus((119889+2120573+2)119902)120573
infininfin(R
119889+1
+)
(67)
H119904
119902120573(R
119889+1
+) =
F119904120573
1199022(R
119889+1
+) 997893rarr
F119904120573
119902infin(R
119889+1
+)
997893rarrF119904minus((119889+2120573+2)119902)120573
infininfin(R
119889+1
+)
(68)
Proof We obtain these results by the similar ideas used in thenonhomogeneous case (cf [6])
Theorem 23 Let 119886 119887 gt 0 and let 1199021 1199022 isin [1infin] Let120579 = 119886(119886 + 119887) isin (0 1) and let 1119901 = (1 minus 120579)1199021 +
1205791199022 Then there exists a constant 119862 such that for every119891 isin
F119886120573
1199021infin(R119889+1
+) cap
Fminus119887120573
1199022infin(R119889+1
+) then one has
1003816100381610038161003816119891 (119909)
1003816100381610038161003816le 119862(sup
119895isinZ
2119886119895 10038161003816100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
1minus120579
(sup119895isinZ
2minus119887119895 10038161003816
100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
120579
(69)
In particular one gets
10038171003817100381710038171198911003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
10038171003817100381710038171198911003817100381710038171003817
1minus120579
F119886120573
1199021infin(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
120579
Fminus119887120573
1199022infin(R119889+1+
) (70)
Journal of Function Spaces and Applications 7
Proof Let 119891 be a Schwartz class we have
1003816100381610038161003816119891 (119909)
1003816100381610038161003816le sum
119895isinZ
10038161003816100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816
le sum
119895isinZ
min(2minus119886119895sup119895isinZ
(2119886119895 10038161003816100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
2119895119887sup119895isinZ
(2minus119895119887 10038161003816
100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816))
(71)
We define119873(119909) as the largest index such that
2119895119887sup119895isinZ
(2minus119895119887 10038161003816
100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816) le 2
minus119886119895sup119895isinZ
(2119886119895 10038161003816100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816) (72)
and we write1003816100381610038161003816119891 (119909)
1003816100381610038161003816le sum
119895le119873(119909)
2119895119887sup119895isinZ
(2minus119895119887 10038161003816
100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
+ sum
119895gt119873(119909)
2minus119886119895sup
119895
(2119886119895 10038161003816100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
le 119862(sup119895isinZ
2119886119895 10038161003816100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
119887(119886+119887)
times (sup119895isinZ
2minus119887119895 10038161003816
100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
119886(119886+119887)
(73)
Thus (69) is proved In order to obtain (70) it is enough toapply the Holder inequality in the expression above since wehave 120579 = 119886(119886+119887) isin (0 1) and let 1119901 = (1minus120579)1199021+1205791199022
Corollary 24 Let 119902 isin (1infin) and let 119904 isin R such that 0 lt 119904 lt
(119889 + 2120573 + 2)119902 then one has
10038171003817100381710038171198911003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
10038171003817100381710038171198911003817100381710038171003817
1minus(119902119901)
Bminus((2120573+2+119889)119902minus119904)120573
infininfin (R119889+1
+ )
10038171003817100381710038171198911003817100381710038171003817
119902119901
B119904120573
119902119902(R119889+1
+ )
(74)
10038171003817100381710038171198911003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
10038171003817100381710038171198911003817100381710038171003817
1minus(119902119901)
Bminus((2120573+2+119889)119902minus119904)120573
infininfin (R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
119902119901
H119904119902120573(R119889+1+
) (75)
where 119901 = 119902(2120573 + 2 + 119889)(2120573 + 2 + 119889 minus 119902119904)
Proof By choosing 119886 = 119904 gt 0 minus119887 = 119904 minus (119889 + 2120573 + 2)119902 lt 01199021 = 119902 and 1199022 = infin we deduce (74) from the relations (70)and (67) In the same way we deduce (75) from the relations(70) and (68)
4 Generalized Heat Equation
41 Characterization for the Weinstein-Besov Spaces TheWeinstein heat equation reads
120597119905119906 (119905 119909) minus Δ 120573119906 (119905 119909) = 119891 (119905 119909) (119905 119909) isin [0infin) timesR119889+1
+
119906|119905=0 = 119892
(76)
We introduce the Weinstein heat semigroup 119867120573(119905) for theWeinstein-Laplace operator
119867120573 (119905) 119892 (119909) =
int
R119889+1+
Γ120573 (119905 119909 119910) 119892 (119910) 119889120583120573 (119910) if 119905 gt 0
119892 (119909) if 119905 = 0(77)
where Γ120573 is the Weinstein heat kernel defined by
Γ120573 (119905 119909 119910) = 120591119909 (119864(120573)
119905) (119910) (78)
where
119864(120573)
119905(119910) =
2
1205871198892Γ (120573 + 1) (4119905)
120573+1+1198892119890minus11991024119905 (79)
Thus
119867120573 (119905) 119892 (119909) = 119892lowast119882119864(120573)
119905 (119909) (80)
In practice we use the integral formulation of (76)
119906 (119905 119909) = 119867120573 (119905) 119892 (119909) + 119866120573 (119891) (119905 119909)
= 119867120573 (119905) 119892 (119909) + int
119905
0
119867120573 (119905 minus 119904) 119891 (119904 119909) 119889119904
(81)
Remark 25 The function 119864(120573)119905
is the Gauss kernel associatedwith Weinstein operators This function satisfies
forall120585 isin R119889+1
+ F119882 (119864
(120573)
119905) (120585) = 119890
minus1199051205852
(82)
Proposition 26 Let 1 le 119901 le 119903 le infin and let 119891 isin 119871119901
120573(R119889+1
+)
Then the operator 119867120573(119905) maps 119871119901
120573(R119889+1
+) continuously to
119871119903
120573(R119889+1
+) and
10038171003817100381710038171003817119867120573 (119905) 119891
10038171003817100381710038171003817119871119903120573(R119889)
le 119862119905minus((119889+2120573+2)2)(1119901minus1119903)1003817
1003817100381710038171198911003817100381710038171003817119871119901
120573(R119889)
(83)
Moreover1003817100381710038171003817100381710038171003817
(minusΔ 120573)
1205752
119867120573 (119905) 119891
1003817100381710038171003817100381710038171003817119871119903120573(R119889)
le 119862119905minus1205752minus((119889+2120573+2)2)(1119901minus1119903)1003817
1003817100381710038171198911003817100381710038171003817119871119901
120573(R119889)
(84)
for all 120575 gt 0
Proof It follows from the relations (80) and (29) combinedwith scaling property of the kernel 119864(120573)
119905
In this section we prove estimates for the Weinstein heatsemigroupThese estimates are based on the following result
Lemma 27 Let C be an annulus Positive constants 119888 and 119862exist such that for any 119901 in [1infin] and any couple (119905 120582) ofpositive real numbers one has
suppF119882 (119906) sub 120582C 997904rArr
10038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
le 119862119890minus1198881199051205822
119906119871119901
120573(R119889+1+
)
(85)
8 Journal of Function Spaces and Applications
Proof We again consider a function Θ in 119863(R119889+1
+ 0) the
value of which is identically 1 in neighborhood of annulusCWe can also assume without loss of generality that 120582 = 1 Wethen have
119867120573 (119905) 119906 = 119892 (119905 sdot) lowast119882119906 (86)where
119892 (119905 sdot) = Fminus1
119882(Θ (120585) 119890
minus1199051205852
) (87)
The lemma is proved provided that we can find positive realnumbers 119888 and 119862 such that
forall119905 gt 01003817100381710038171003817119892 (119905 sdot)
10038171003817100381710038171198711120573(R119889+1+
)le 119862119890
minus119888119905 (88)
To begin we perform integrations by parts in (87) We get1003816100381610038161003816119892 (119905 119909)
1003816100381610038161003816=
1
119888120573
(1 + 1199092)
minus(119889+[2120573]+3)
times int
R119889+1+
Λ (119909 120585) (119868119889 minus Δ 120573)
119889+[2120573]+3
times (Θ (120585) 119890minus1199051205852
) 119889120583120573 (120585)
(89)
Using Leibnizrsquos formula we obtain1003816100381610038161003816119892 (119905 119909)
1003816100381610038161003816le 119862(1 + 119909
2)
minus(119889+[2120573]+3)
119890minus119888119905 (90)
and (88) follows
For any interval 119868 of R (bounded or unbounded) wedefine themixed space-time 119871119901(119868 119871119902
120573(R119889+1
+)) Banach space of
(classes of) measurable functions 119906 119868 rarr 119871119902
120573(R119889+1
+) such
that 119906119871119901(119868119871
119902
120573(R119889+1+
))lt infin with
119906119871119901(119868119871119902
120573(R119889+1+
))= (int
119868
119906 (119905 sdot)119901
119871119902
120573(R119889+1+
)119889119905)
1119901
if 1 le 119901 119902 lt infin
119906119871infin(119868119871119902
120573(R119889+1+
))= ess sup
119905isin119868
119906 (119905 sdot)119871119902
120573(R119889+1+
) if 1 le 119902 lt infin
(91)Corollary 28 Let C be an annulus and 120582 a positive realnumber Let 1199060 (resp 119891 = 119891(119905 119909)) satisfy suppF119882(1199060) sub 120582C(resp suppF119882(119891(119905 sdot)) sub 120582C for all 119905 in [0 119879]) Consider 119906 asolution of
120597119905119906 minus Δ 120573119906 = 0 119906|119905=0 = 1199060 (92)and V a solution of
120597119905V minus Δ 120573V = 119891 (119905 sdot) V|119905=0 = 0 (93)There exist positive constants 119888 and 119862 depending only on Csuch that for any 1 le 119886 le 119887 le infin and 1 le 119901 le 119902 le infin we have
119906119871119902([0119879]119871119887120573(R119889+1+
))le 119862120582
(119889+2120573+2)(1119886minus1119887)120582minus21199021003817
1003817100381710038171199060
1003817100381710038171003817119871119886120573(R119889+1+
)
V119871119902([0119879]119871119887120573(R119889+1+
))le 119862120582
minus2(1+1119902minus1119901)120582(119889+2120573+2)(1119886minus1119887)
times10038171003817100381710038171198911003817100381710038171003817119871119901([0119879]119871119886
120573(R119889+1+
))
(94)
Proof It suffices to use the fact that
119906 (119905 sdot) = 119867120573 (119905) 1199060 V (119905 sdot) = int119905
0
119867120573 (119905 minus 119904) 119891 (119904 sdot) 119889119904
(95)
Combining Lemma 27 and Youngrsquos inequality (29) withscaling property of the kernel 119864(120573)
119905now yields the result
Theorem 29 Let 119904 be a positive real number and (119901 119903) isin
[1infin]2 A constant 119862 exists which satisfies the following
property For 119906 isin Bminus2119904120573
119901119903 (R119889+1
+) one has
119862minus1119906
Bminus2119904120573
119901119903(R119889+1+
)le
10038171003817100381710038171003817100381710038171003817
10038171003817100381710038171003817119905119904119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
10038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
le 119862119906Bminus2119904120573
119901119903(R119889+1+
)
(96)
To prove this result we need the following lemma
Lemma 30 There exist two positive constants 120581 and 119862
depending only on 120593 such that for all 1 le 119901 le infin 120591 ge 0 and119895 isin Z one has
10038171003817100381710038171003817Δ 119895 (119867120573 (120591) 119906)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862119890
minus1205812211989512059110038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
) (97)
Proof The result follows immediately by applying Lemma 27and because Δ 119895(119867120573(120591))119906 = (119867120573(120591)Δ 119895)119906
Proof of Theorem 29 Using Lemma 30 and considering thefact that the operator Δ 119895 commutes with the operator 119867120573(119905)
and the definition of the homogeneous Weinstein-Besov(semi) norm we get
10038171003817100381710038171003817119905119904119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862119906
Bminus2119904120573
119901119903(R119889+1+
)sum
119895isinZ
11990511990422119895119904119890minus12058111990522119895
119888119903119895
(98)
where (119888119903119895)119895isinZ denotes as in all this proof a generic elementof the unit sphere of 119897119903(Z) In the case when 119903 = infin therequired inequality comes immediately from the followingeasy result For any positive 119904 we have
sup119905gt0
sum
119895isinZ
11990511990422119895119904119890minus12058111990522119895
lt infin (99)
In the case 119903 lt infin using the Holder inequality with theweight 22119895119904119890minus1205811199052
2119895
(99) and the Fubini theorem we obtain
int
infin
0
11990511990311990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)
119889119905
119905
le 119862119906119903
Bminus2119904120573
119901119903(R119889+1+
)int
infin
0
(sum
119895isinZ
11990511990422119895119904119890minus12058111990522119895
)
119903minus1
times (sum
119895isinZ
11990511990422119895119904119890minus12058111990522119895
119888119903
119903119895)
119889119905
119905
Journal of Function Spaces and Applications 9
le 119862119906119903
Bminus2119904120573
119901119903(R119889+1+
)int
infin
0
(sum
119895isinZ
11990511990422119895119904119890minus12058111990522119895
119888119903
119903119895)
119889119905
119905
le 119862119906119903
Bminus2119904120573
119901119903(R119889+1+
)sum
119895isinZ
119888119903
119903119895int
infin
0
(11990511990422119895119904119890minus12058111990522119895
)
119889119905
119905
le 119862Γ (119904) 119906119903
Bminus2119904120573
119901119903(R119889+1+
)
(100)
In order to prove the other inequality let us observe thatfor any 119904 greater than minus1 we have
Δ 119895119906 =
1
Γ (119904 + 1)
int
infin
0
119905119904(minusΔ 120573)
119904+1
119867120573 (119905) Δ 119895119906 119889119905 (101)
Then Lemma 30 Proposition 9 and the fact that the operatorΔ 119895 commutes with the operator119867120573(119905) lead to the following
10038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862int
infin
0
11990511990422119895(119904+1)
119890minus1205811199052211989510038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889119905
(102)
In the case 119903 = infin we simply write
10038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862(sup
119905gt0
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
times int
infin
0
22119895(119904+1)
119890minus12058111990522119895
119889119905
le 11986222119895119904(sup119905gt0
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
(103)
In the case 119903 lt infin Holderrsquos inequality with the weight 119890minus12058111990522119895
gives
(int
infin
0
119905119904119890minus1205811199052211989510038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889119905)
119903
le 1198622minus2119895(119903minus1)
int
infin
0
119905119903119904119890minus1205811199052211989510038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)119889119905
(104)
Thanks to (99) and Fubinirsquos theorem we infer from (102) that
sum
119895isinZ
2minus211989511990311990410038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)le 119862int
infin
0
11990511990311990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)
119889119905
119905
(105)
The theorem is proved
Second Proof ofTheorem 29We only consider the case 1 le 119903 ltinfinThe case 119903 = infin can be shown similarlyWe first prove that
119862minus1119906
Bminus2119904120573
119901119903(R119889+1+
)le
10038171003817100381710038171003817100381710038171003817
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
10038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
(106)
It is easy to see that
Δ 119895119906 = 120594119895lowast119882119864(120573)
2minus2119895lowast119882119906
(107)
where 120594119895 = Fminus1
119882(120593(2
minus119895120585)119890
2minus21198951205852
) and119864(120573)2minus2119895
is the Gauss kernelassociated with Weinstein operators By relation (29) we get
10038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le
10038171003817100381710038171003817120594119895
100381710038171003817100381710038171198711120573(R119889+1+
)
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
) (108)
As10038171003817100381710038171003817120594119895
100381710038171003817100381710038171198711120573(R119889+1+
)= int
R119889+1+
100381610038161003816100381610038161003816F
minus1
119882(120593 (120585) 119890
1205852
)
100381610038161003816100381610038161003816119889120583120573 (120585) lt infin (109)
we obtain10038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
) (110)
Moreover simple calculations give that
119864(120573)
2minus2119895lowast119882119906 = 119867120573 (2
minus4119895minus 119905
2) (119864
(120573)
1199052lowast119882119906)
(111)
Thus from Proposition 26 it follows that100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
100381710038171003817100381710038171003817119864(120573)
1199052lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1
+ )
(112)
for any 119905 isin [2minus119895minus1 2minus119895] which implies that
sum
119895isinZ
2minus211990411989511990310038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)
le 119862 sum
119895isinZ
int
2minus119895
2minus119895minus1(119905
2119904100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903119889119905
119905
le 119862int
infin
0
(1199052119904100381710038171003817100381710038171003817119864(120573)
1199052lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903119889119905
119905
le 119862int
infin
0
(11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903119889119905
119905
(113)
where we have used the fact that 119864(120573)1199052lowast119882119906 = 119867120573(119905
2)119906
We now prove that10038171003817100381710038171003817100381710038171003817
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
10038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
le 119862119906Bminus2119904120573
119901119903(R119889+1+
) (114)
Indeed one has
119864(120573)
2minus2119895lowast119882119906 = sum
119899isinZ
119864(120573)
2minus2119895lowast119882Δ 119899+119895119906 (115)
Arguing as above we have100381710038171003817100381710038171003817119864(120573)
1199052lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1
+ )
(116)
for any 119905 isin [2minus119895 21minus119895] Thus10038171003817100381710038171003817100381710038171003817
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
10038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
= 2
100381710038171003817100381710038171003817100381710038171003817
1003817100381710038171003817100381710038171199052119904119864(120573)
1199052lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)
100381710038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
le 119862 sum
119895isinZ
int
21minus119895
2minus119895(2
minus2119895119904100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903119889119905
119905
le 119862 sum
119895isinZ
(2minus2119895119904
sum
119899isinZ
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
(117)
10 Journal of Function Spaces and Applications
On the other hand it is easy to see that100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)le 1198622
minus211989911990410038171003817100381710038171003817Δ 119899+119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
) (118)
for any 119904 gt 0 For 0 lt 1199041 lt 119904 lt 1199042 and by using theMinkowskiinequality we have
sum
119895isinZ
(2minus2119895119904
sum
119899isinZ
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
le sum
119895isinZ
(2minus2119895119904
0
sum
minusinfin
2minus21198991199041
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
+ sum
119895isinZ
(2minus2119895119904
sum
119899isinN
2minus21198991199042
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
le 119862(
0
sum
minusinfin
2minus2119899(119904
1minus119904)(sum
119895isinZ
(2minus2(119899+119895)11990311990410038171003817
100381710038171003817Δ 119899+119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
)
1119903
)
119903
+ 119862(sum
N
2minus2119899(119904
2minus119904)(sum
119895isinZ
(2minus2(119899+119895)11990311990410038171003817
100381710038171003817Δ 119899+119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
)
1119903
)
119903
le 119862 sum
119895isinZ
2minus211989511990311990410038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)
(119)
The result is immediately from (117) and (119)
42 Embedding Sobolev Theorems
Theorem 31 Let 1 lt 119901 lt infin and let 0 lt 119904 lt (119889 + 2120573 +
2)119901There exists a positive constant119862 such that for all function119891 isin
H119904
119901120573(R119889+1
+) one has
10038171003817100381710038171198911003817100381710038171003817119871119902
120573(R119889+1+
)le 119862
10038171003817100381710038171198911003817100381710038171003817
1minus120579
H119904119901120573(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
120579
B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
) (120)
where 120579 = 119904119901(119889+2120573+2) and 119902 = 119901(119889+2120573+2)(119889+2120573+2minus119901119904)
Proof Bydensity we can suppose that119891belongs toSlowast(R119889+1
)It is easy to see that
119891 = int
infin
0
119867120573 (119905) Δ 120573119891119889119905(121)
and decompose the integral in two parts as follows
119891 = int
119860
0
119867120573 (119905) Δ 120573119891119889119905 + int
infin
119860
119867120573 (119905) Δ 120573119891119889119905(122)
where 119860 is a constant to be fixed laterOn the other hand byTheorem 29 we obtain10038171003817100381710038171003817119867120573 (119905) Δ 120573119891
10038171003817100381710038171003817119871infin120573(R119889+1+
)
le
119862
1199051minus(12)(119904minus(119889+2120573+2)119901)
10038171003817100381710038171198911003817100381710038171003817B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
)
(123)
Therefore after integrating we get
int
infin
119860
10038171003817100381710038171003817119867120573 (119905) Δ 120573119891
10038171003817100381710038171003817119871infin120573(R119889+1+
)119889119905
le 119860(12)(119904minus(119889+2120573+2)119901)1003817
1003817100381710038171198911003817100381710038171003817B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
)
(124)
On the other hand denoting 119892 = (minusΔ 120573)1199042119891 we have
119867120573 (119905) Δ 120573119891 =
1
(minus119905)1minus1199042
119867120573 (119905) (minus119905Δ 120573)
1minus1199042
119892 (125)
We proceed as in [8] we prove that1003816100381610038161003816100381610038161003816
119867120573 (119905) (minus119905Δ 120573)
1minus1199042
119892 (119909)
1003816100381610038161003816100381610038161003816
le 119862 (119904)119872120573 (119892) (119909) (126)
where119872120573(119892) is a maximal function of 119892 associated with theWeinstein operators (cf [12])
This leads to100381610038161003816100381610038161003816100381610038161003816
int
119860
0
119867120573 (119905) Δ 120573119891 (119909) 119889119905
100381610038161003816100381610038161003816100381610038161003816
le 1198621198601199042119872120573 (119892) (119909) (127)
In conclusion we get10038161003816100381610038161003816100381610038161003816
int
infin
0
119867120573 (119905) Δ 120573119891 (119909) 119889119905
10038161003816100381610038161003816100381610038161003816
le 119862 (1198601199042119872120573 (119892) (119909)
+119860(12)(119904minus(119889+2120573+2)119901)1003817
1003817100381710038171198911003817100381710038171003817B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
))
(128)
and the choice of 119860 such that
119860(119889+2120573+2)2119901
119872120573 (119892) (119909) =10038171003817100381710038171198911003817100381710038171003817B119904minus(119889+2120573+2)119901120573
infininfin (R119889+1+
)(129)
ensures that10038161003816100381610038161003816100381610038161003816
int
infin
0
119867120573 (119905) Δ 120573119891 (119909) 119889119905
10038161003816100381610038161003816100381610038161003816
le 119862(119872120573(119892)(119909))
1minus(119901119904(119889+2120573+2))10038171003817100381710038171198911003817100381710038171003817
119901119904(119889+2120573+2)
B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
)
(130)
Finally taking the 119871119902120573norm with 119902 = 119901(119889 + 2120573 + 2)(119889 + 2120573 +
2minus119901119904) ends the proof thanks to the fact themaximal function119872120573 is bounded of 119871119902
120573(R119889+1
+) into itself for 119902 gt 1
Theorem 32 Let 1 lt 119901 lt 119902 lt infin For all function 119891 such that119891 isin
H1199041
119901120573(R119889+1
+)⋂
Bminus120573120573
infininfin(R119889+1
+) one has
10038171003817100381710038171198911003817100381710038171003817H119904119901120573(R119889+1+
)le 119862
10038171003817100381710038171198911003817100381710038171003817
120579
H1199041
119901120573(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
1minus120579
Bminus120573120573
infininfin(R119889+1
+) (131)
where 120579 = 119901119902 119904 = 1205791199041 minus (1 minus 120579)120573 with 120573 gt 0 minus120573 lt 119904 lt 1199041
Proof It suffices to prove that1003817100381710038171003817100381710038171003817
(minusΔ 120573)
(119904minus1199041)2
119891
1003817100381710038171003817100381710038171003817119871119902
120573(R119889+1+
)
le 11986210038171003817100381710038171198911003817100381710038171003817
120579
119871119901
120573(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
1minus120579
Bminus120573minus1199041120573
infininfin (R119889+1+
)
(132)
Journal of Function Spaces and Applications 11
Indeed we use the following identity (which may be easilyproven by taking the Weinstein transform in 119909 of both sides)
(minusΔ 120573)
minus1205752
119891 (119909) =
1
Γ (1205752)
int
infin
0
1199051205752minus1
119867120573 (119905) 119891 (119909) 119889119905 (133)
with 120575 = 1199041 minus 119904 gt 0We decompose the integral in two parts as follows
(minusΔ 120573)
minus1205752
119891 (119909) =
1
Γ (1205752)
int
119879
0
1199051205752minus1
119867120573 (119905) 119891 (119909) 119889119905
+
1
Γ (1205752)
int
infin
119879
1199051205752minus1
119867120573 (119905) 119891 (119909) 119889119905
(134)
where 119879 is a constant to be fixed laterWe proceed as in [8] we obtain
10038161003816100381610038161003816119867120573 (119905) 119891 (119909)
10038161003816100381610038161003816le 119862119872120573 (119891) (119909) (135)
On the other hand we use Theorem 29 and the fact that 119891belongs to Bminus120573minus119904
1120573
infininfin(R119889+1
+) to deduce that
10038161003816100381610038161003816119867120573 (119905) 119891 (119909)
10038161003816100381610038161003816le 119862119905
(minus120573minus1199041)210038171003817100381710038171198911003817100381710038171003817Bminus120573minus1199041120573
infininfin (R119889+1+
) (136)
Thus by applying the preceding estimates on the right part of(134) we obtain
1003816100381610038161003816100381610038161003816
(minusΔ 120573)
minus1205752
119891 (119909)
1003816100381610038161003816100381610038161003816
le
1198621
Γ (1205752)
1198791205752119872120573 (119891) (119909)
+
1198622
Γ (1205752)
119879(120575minus120573minus119904
1)210038171003817100381710038171198911003817100381710038171003817Bminus120573minus1199041120573
infininfin (R119889+1+
)
(137)
We fix now
119879 = (
10038171003817100381710038171198911003817100381710038171003817Bminus120573minus1199041120573
infininfin (R119889+1+
)
119872120573 (119891) (119909)
)
2(120573+1199041)
(138)
We obtain
1003816100381610038161003816100381610038161003816
(minusΔ120573)
minus1205752
119891 (119909)
1003816100381610038161003816100381610038161003816
le
1198621 + 1198622
Γ (1205752)
(119872120573(119891)(119909))
12057910038171003817100381710038171198911003817100381710038171003817
1minus120579
Bminus120573minus1199041120573
infininfin (R119889+1+
)
(139)
Thus we deduce that1003817100381710038171003817100381710038171003817
(minusΔ120573)
minus1205752
119891
1003817100381710038171003817100381710038171003817119871119902
120573(R119889+1+
)
le
1198621 + 1198622
Γ (1205752)
10038171003817100381710038171003817119872120573 (119891)
10038171003817100381710038171003817
120579
119871119901
120573(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
1minus120579
Bminus120573minus1199041120573
infininfin (R119889+1+
)
(140)
To conclude we used the fact that the maximal function119872120573
is bounded of 119871119902120573(R119889+1
+) into itself for 119902 gt 1
43 Estimates in Generalized Besov Spaces For any interval 119868ofR (bounded or unbounded) and a normed space 119865(R119889+1
+)
we define the mixed space-time 119871119901(119868 119865(R119889+1
+)) space of
(classes of) measurable functions 119906 119868 rarr 119865(R119889+1
+) such that
||119906||119871119901(119868119865(R119889+1+
)) lt infin with
119906119871119901(119868119865(R119889+1+
)) = (int
119868
119906 (119905 sdot)119901
119865(R119889+1+
)119889119905)
1119901
if 1 le 119901 lt infin
119906119871infin(119868119865(R119889+1+
)) = ess sup119905isin119868
119906 (119905 sdot)119865(R119889+1+
)
(141)
For any interval 119868 of R (bounded or unbounded) anda Banach space 119883 we define the mixed space-time 119862(119868119883)space of continuous functions 119868 rarr 119883 When 119868 is bounded119862(119868119883) is a Banach space with the norm of 119871infin(119868 119883)
Theorem 33 Let 119904 isin R and 1 le 119901 119902 119903 le infin Let 119879 gt 0 119892 isin
B119904120573
119901119903(R119889+1
+) and119891 in 119871119902((0 119879) B
119904minus2+(2119902)120573
119901119903 (R119889+1
+)) Then (76)
has a unique solution
119906 isin 119871119902((0 119879)
B119904+(2119902)120573
119901119903(R
119889+1
+))
⋂119871infin((0 119879)
B119904120573
119901119903(R
119889+1
+))
(142)
and there exists a constant 119862 such that for all 1199021 isin [119902infin] onehas
1199061198711199021 ((0119879)B
119904+(21199021)120573
119901119903(R119889+1+
))
le 119862(10038171003817100381710038171198921003817100381710038171003817B119904120573
119901119903(R119889+1+
)+10038171003817100381710038171198911003817100381710038171003817119871119902((0119879)B
119904minus2+(2119902)120573
119901119903(R119889+1+
)))
(143)
If in addition 119903 lt infin then 119906 isin 119862([0 119879] B119904120573
119901119903(R119889+1
+))
Proof Since 119892 and 119891 are temperate distributions (76) has aunique solution 119906 in S1015840
((0 119879) timesR119889+1
+) which satisfies
F119882 (119906) (119905 120585) = 119890minus1199051205852
F119882 (119892) (120585)
+ int
119905
0
119890(120591minus119905)120585
2
F119882 (119891) (120591 120585) 119889120591
(144)
Next we notice that applying Δ 119895 to (76) and using formula(81) yield
Δ 119895119906 (119905 sdot) = 119867120573 (119905) Δ 119895119892 + int
119905
0
119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot) 119889120591(145)
Therefore
10038171003817100381710038171003817Δ 119895119906 (119905 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le
10038171003817100381710038171003817119867120573(119905)Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+ int
119905
0
10038171003817100381710038171003817119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591
(146)
12 Journal of Function Spaces and Applications
By virtue of Lemma 30 we thus have for some 120581 gt 0
10038171003817100381710038171003817Δ 119895119906(119905 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
le 119862[119890minus1205812211989511990510038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+ int
119905
0
119890minus12058122119895(119905minus120591) 10038171003817
100381710038171003817Δ 119895119891 (120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591]
(147)
Applying convolution inequalities we get
10038171003817100381710038171003817Δ 119895119906
100381710038171003817100381710038171198711199021 ((0119879)119871
119901
120573(R119889+1+
))
le 119862[
[
((
1 minus 119890minus120581119879119902122119895
120581119902122119895
)
11199021
)
10038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+((
1 minus 119890minus120581119879119902222119895
120581119902222119895
)
11199022
)
10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119902((0119879)119871
119901
120573(R119889+1+
))
]
]
(148)
with 11199022 = 1+ 11199021 minus1119902 Finally taking the 119897119903(Z) norm we
conclude that (with the usual convention if 119903 = infin)
1199061198711199021 ((0119879)B
119904+(21199021)120573
119901119903(R119889+1+
))
le 119862[
[
sum
119895isinZ
((
1 minus 119890minus120581119879119902122119895
120581119902122119895
)
1199031199021
)(211989511990410038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
]
]
1119903
+ 119862[
[
sum
119895isinZ
((
1 minus 119890minus120581119879119902222119895
120581119902222119895
)
1199031199022
)
times (2119895(119904minus2+2119902)10038171003817
100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119902(0119879119871
119901
120573(R119889+1+
))
119903
]
]
1119903
(149)
which insures that 119906 isin 119871119902((0 119879)
B119904+(2119902)120573
119901119903 (R119889+1
+))
⋂119871infin((0 119879)
B119904120573
119901119903(R119889+1
+)) and yields the desired inequality
Since 119906 belongs to 119862([0 119879]B119904120573
119901119903(R119889+1
+)) in the case where
119903 is finite may be easily deduced from the density ofSlowast(R
119889+1)⋂
B119904120573
119901119903(R119889+1
+) in B
119904120573
119901119903(R)
Theorem 34 Let 119904 isin R 119879 gt 0 and 1 le 119901 119902 119903 le infinOne supposes that 119892 isin 119861
119904120573
119901119903(R119889+1
+) and 119891 isin 119871
119902((0 119879)
119861119904minus2+(2119902)120573
119901119903 (R119889+1
+)) Then (76) has a unique solution 119906 belong-
ing to
119871119902((0 119879) 119861
119904+(2119902)120573
119901119903(R
119889+1
+))⋂119871
infin((0 119879) 119861
119904120573
119901119903(R
119889+1
+))
(150)
and there exists a constant 119862 such that for all 119902 le 1199021 le infin
1199061198711199021 ((0119879)119861
119904+(21199021)120573
119901119903(R119889+1+
))
le 119862 [ (1 + 11987911199021)10038171003817100381710038171198921003817100381710038171003817119861119904120573
119901119903(R119889+1+
)
+ (1 + 1198791+1119902
1minus1119902
)10038171003817100381710038171198911003817100381710038171003817119871119902((0119879)119861
119904minus2+(2119902)120573
119901119903(R119889+1+
))]
(151)
If in addition 119903 lt infin then 119906 isin 119862([0 119879] 119861119904120573119901119903(R119889+1
+))
Proof Since 119892 119891 are tempered (76) has a unique solution 119906in S1015840
((0 119879) timesR119889+1
+) satisfying
F119882 (119906) (119905 120585) = 119890minus1199051205852
F119882 (119892) (120585)
+ int
119905
0
119890(120591minus119905)120585
2
F119882 (119891) (120591 120585) 119889120591
(152)
Hence applying Δ 119895 119895 ge 0 to (81) we see that
Δ 119895119906 (119905 sdot) = 119867120573 (119905) Δ 119895119892 + int
119905
0
119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot) 119889120591(153)
and thus by Lemma 30 we can deduce that10038171003817100381710038171003817Δ 119895119906 (119905 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
le
10038171003817100381710038171003817119867120573(119905)Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)+ int
119905
0
10038171003817100381710038171003817119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591
le 119862[119890minus1205812211989511990510038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+int
119905
0
119890minus12058122119895(119905minus120591)10038171003817
100381710038171003817Δ 119895119891(120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591]
(154)
Then it follows from convolution inequalities thatΔ 1198951199061198711199021 ((0119879)119871
119901
120573(R119889+1+
))is dominated by
(
1 minus 119890minus120581119879119902122119895
120581119902122119895
)
11199021
10038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119861119904120573
119901119903(R119889+1+
)
+ (
1 minus 119890minus120581119879119902222119895
120581119902222119895
)
11199022
10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119902((0119879)119871
119901
120573(R119889+1+
))
(155)
with 11199022 = 1 + 11199021 minus 1119902 Moreover similarly as above wecan obtain that
1003817100381710038171003817Δminus1119906(119905 sdot)
1003817100381710038171003817119871119901
120573(R119889+1+
)le1003817100381710038171003817Δminus1119892
1003817100381710038171003817119871119901
120573(R119889+1+
)
+ int
119905
0
1003817100381710038171003817Δminus1119891 (120591 sdot)
1003817100381710038171003817119871119901
120573(R119889+1+
)119889120591
(156)
and thus if 1 le 119902 le 1199021 le infin1003817100381710038171003817Δminus1119906
10038171003817100381710038171198711199021 ((0119879)119871
119901
120573(R119889+1+
))
le 119862(119879111990211003817100381710038171003817Δminus1119892
1003817100381710038171003817119871119901
120573(R119889+1+
)+ 119879
111990221003817100381710038171003817Δminus1119891
1003817100381710038171003817119871119902((0119879)119871
119901
120573(R119889+1+
)))
(157)
Journal of Function Spaces and Applications 13
Finally taking the 119897119903-normwith respect to 119895 in (155) and (157)with the usual convention if 119903 = infin we can deduce the desiredestimate
Acknowledgment
Theauthor gratefully acknowledges theDeanship of ScientificResearch at the University of Taibah The author is deeplyindebted to the referee for providing constructive commentsand help in improving the contents of this paper
References
[1] Z Ben Nahia and N Ben Salem ldquoSpherical harmonics andapplications associated with the Weinstein operatorrdquo in Pro-ceedings of the International Conference on PotentialTheory heldin Kouty Czech Republic (ICPT rsquo94) pp 235ndash241 1996
[2] Z Ben Nahia and N Ben Salem ldquoOn a mean value propertyassociated with the Weinstein operatorrdquo in Proceedings of theInternational Conference on Potential Theory held in KoutyCzech Republic (ICPT rsquo94) pp 243ndash253 1996
[3] M Brelot ldquoEquation de Weinstein et potentiels de MarcelRieszrdquo in Seminaire de Theorie de Potentiel Paris No 3 vol 681of Lecture Notes in Mathematics pp 18ndash38 Springer BerlinGermany 1978
[4] H Mejjaoli and M Salhi ldquoUncertainty principles for theweinstein transformrdquo Czechoslovak Mathematical Journal vol61 no 4 pp 941ndash974 2011
[5] H Mejjaoli and A Ould Ahmed Salem ldquoWeinstein Gabortransform and applicationsrdquo Advanced Studies in Pure Mathe-matics vol 2 no 3 pp 203ndash210 2012
[6] H Mejjaoli ldquoBesov spaces associated withthe Weinstein opera-tor and applicationsrdquo In press
[7] T Kawazoe and H Mejjaoli ldquoGeneralized Besov spaces andtheir applicationsrdquo Tokyo Journal of Mathematics vol 35 no 2pp 297ndash320 2012
[8] H Mejjaoli ldquoLittlewood-Paley decomposition associated withthe Dunkl operators and paraproduct operatorsrdquo Journal ofInequalities in Pure and Applied Mathematics vol 9 no 4 pp1ndash25 2008
[9] H Mejjaoli and N Sraeib ldquoGeneralized sobolev spaces inquantum calculus and applicationsrdquo Journal of Inequalities andSpecial Functions vol 1 no 4 pp 43ndash64 2012
[10] H Mejjaoli ldquoGeneralized homogeneous Besov spaces and theirapplicationsrdquo Serdica Mathematical Journal vol 38 no 4 pp575ndash614 2012
[11] H Triebel Interpolation Theory Functions Spaces DifferentialOperators North-Holland AmsterdamThe Netherlands 1978
[12] V S Guliev ldquoOn maximal function and fractional integralassociated with the Bessel differential operatorrdquo MathematicalInequalities and Applications vol 6 no 2 pp 317ndash330 2003
Submit your manuscripts athttpwwwhindawicom
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Differential EquationsInternational Journal of
Volume 2014
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Probability and StatisticsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
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Mathematical PhysicsAdvances in
Complex AnalysisJournal of
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OptimizationJournal of
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CombinatoricsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
International Journal of
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Operations ResearchAdvances in
Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Function Spaces
Abstract and Applied AnalysisHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
International Journal of Mathematics and Mathematical Sciences
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Algebra
Discrete Dynamics in Nature and Society
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
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Decision SciencesAdvances in
Discrete MathematicsJournal of
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Volume 2014 Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Stochastic AnalysisInternational Journal of
Journal of Function Spaces and Applications 5
Definition 10 Let 119904 isin R and 119901 119902 isin [1infin]The homogeneousWeinstein-Besov spaces B
119904120573
119901119902(R119889+1
+) are the spaces of distri-
bution in S1015840
ℎ120573lowast(R119889+1
) such that
10038171003817100381710038171198911003817100381710038171003817B119904120573
119901119902(R119889+1+
)= (sum
119895isinZ
(211990411989510038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119902
)
1119902
lt infin (44)
Proposition 11 (see [6]) Let 119904 isin R and 119901 and 119902 two elementsof [1infin] the space B
119904120573
119901119902(R119889+1
+) is the set of 119891 isin S1015840
ℎ120573lowast(R119889+1
)
verifying
10038171003817100381710038171003817
119891
10038171003817100381710038171003817B119904120573
119901119902(R119889+1+
)= (int
infin
0
(119905minus1199041003817100381710038171003817119891lowast119882120601119905
1003817100381710038171003817119871119901
120573(R119889+1+
))
119902119889119905
119905
)
1119902
lt infin
(45)
where 120601119905(119909) = (11199052120573+2+119889
)120601(119909119905) for all 119905 isin (0infin) and 119909 isin
R119889+1
+
Definition 12 For 119904 isin R and 119901 119902 isin [1infin] one writes10038171003817100381710038171198911003817100381710038171003817119861119904120573
119901119902(R119889+1+
)=10038171003817100381710038171198780119891
1003817100381710038171003817119871119901
120573(R119889+1+
)
+ (sum
119895ge1
(211990411989510038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119902
)
1119902
(46)
The nonhomogeneous Besov space 119861119904120573119901119902(R119889+1
+) associated
with the Weinstein operators is defined by
119861119904120573
119901119902(R
119889+1
+) = 119891 isin S
1015840(R
119889)
10038171003817100381710038171198911003817100381710038171003817119861119904120573
119901119902(R119889+1+
)lt infin (47)
We give now another definition equivalent to the nonho-mogeneous Besov space 119861119904120573119901119902(R119889+1
+)
Proposition 13 Let 119904 isin R and119901 and 119902 two elements of [1infin]the space 119861119904120573119901119902(R119889+1
+) is the set of 119891 isin S1015840
(R119889) verifying
10038171003817100381710038171003817
119891
10038171003817100381710038171003817119861119904120573
119901119902(R119889+1+
)=1003817100381710038171003817119891lowast119882120595
1003817100381710038171003817119871119901
120573(R119889+1+
)
+ (int
1
0
(119905minus1199041003817100381710038171003817119891lowast119882120601119905
1003817100381710038171003817119871119901
120573(R119889+1+
))
119902119889119905
119905
)
1119902
lt infin
(48)
Definition 14 Let 119904 isin R and 1 le 119901 119902 le infin the homogeneousWeinstein-Triebel-Lizorkin space F
119904120573
119901119902(R119889+1
+) is the space of
distribution in S1015840
ℎ120573lowast(R119889+1
) such that
10038171003817100381710038171198911003817100381710038171003817F119904120573
119901119902(R119889+1+
)=
100381710038171003817100381710038171003817100381710038171003817100381710038171003817
(sum
119895isinZ
211990411989511990210038161003816100381610038161003816Δ 119895119891
10038161003816100381610038161003816
119902
)
1119902100381710038171003817100381710038171003817100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)
lt infin (49)
Definition 15 For 119904 isin R the operatorR119904
120573from S1015840
ℎ120573lowast(R119889+1
)
to S1015840
ℎ120573lowast(R119889+1
) is defined by
R119904
120573(119891) = F
minus1
119882(sdot
119904F119882119891) (50)
The operatorRminus119904
120573is called Weinstein-Riesz potential space
Definition 16 For 119904 isin R and 1 le 119901 le infin the homogeneousWeinstein-Riesz potential space H119904
119901120573(R119889+1
+) is defined
as the space Rminus119904
120573(119871
119901
120573(R119889+1
+)) equipped with the norm
119891H119904119901120573(R119889+1+
)= R119904
120573(119891)
119871119901
120573(R119889+1+
)
Proposition 17 Let 119904 isin R and 1 le 119901 119902 le infinThe operator Δ 120573 is a linear continuous operator from
B119904120573
119901119902(R119889+1
+) into B
119904minus2120573
119901119902 (R119889+1
+) and from H119904
119901120573(R119889+1
+) into
H119904minus2
119901120573(R119889+1
+)
Proof We obtain these results by the similar ideas used in thenonhomogeneous case (cf [6])
Proposition 18 Let 119904 119905 isin R and 1 le 119901 119902 le infin The operatorR119905
120573is a linear continuous injective operator from B
119904120573
119901119902(R119889+1
+)
onto B119904minus119905120573
119901119902 (R119889+1
+) and from H119904
119901120573(R119889+1
+) onto H119904minus119905
119901120573(R119889+1
+)
Proof We obtain these results by the similar ideas used in thenonhomogeneous case (cf [6])
33 Embeddings As in the Euclidean case (cf [11]) themono-tone character of 119897119902-spaces and the Minkowskis inequalityyield the following
Proposition 19 If 1 le 1199021 lt 1199022 le infin one has
B119904120573
1199011199021
(R119889+1
+) 997893rarr
B119904120573
1199011199022
(R119889+1
+) (1 le 119901 le infin 119904 isin R)
(51)
MoreoverB119904120573
1199011(R
119889+1
+) 997893rarr
H119904
119901120573(R
119889+1
+) 997893rarr
B119904120573
119901infin(R
119889+1
+)
(1 le 119901 le infin 119904 isin R)
(52)
If 1199040 = 1199041 one also has
(H1199040
119901120573(R
119889+1
+)
H1199041
119901120573(R
119889+1
+))
120579119902=
B119904120573
119901119902(R
119889+1
+)
(1 le 119901 119902 le infin 120579 isin (0 1))
(53)
where 119904 = (1 minus 120579)1199040 + 1205791199041
Proposition 20 One assumes that 119904 minus (119889 + 2120573 + 2)119901 = 1199041 minus
(119889 + 2120573 + 2)1199011 Then the following inclusion holds
B119904120573
119901119902(R
119889+1
+) 997893rarr
B1199041120573
11990111199021
(R119889+1
+)
(1 le 119901 le 1199011 le infin 1 le 119902 le 1199021 le infin 119904 1199041 isin R)
(54)
Proof In order to prove the inclusion we use the estimate
Δ 119895119891 = 2119895(119889+2120573+2)
120601 (2119895sdot) lowast119882Δ 119895119891 (55)
Proposition 9(i) gives that10038171003817100381710038171003817Δ 119895119891
100381710038171003817100381710038171198711199011
120573(R119889+1+
)=
100381710038171003817100381710038172119895(119889+2120573+2)
120601 (2119895sdot) lowast119882Δ 119895119891
100381710038171003817100381710038171198711199011
120573(R119889+1+
)
le 1198622119895(119889+2120573+2)(1119901minus1119901
1)10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
(56)
6 Journal of Function Spaces and Applications
By definition of the homogeneous Weinstein-Besov spaceswe therefore infer10038171003817100381710038171198911003817100381710038171003817B1199041120573
11990111199021(R119889+1+
)
= (
infin
sum
119895=minusinfin
(2119895119904110038171003817100381710038171003817Δ 119895119891
100381710038171003817100381710038171198711199011
120573(R119889+1+
))
1199021
)
11199021
le 119862(sum
119895isinZ
(211989511990412119895(119889+2120573+2)(1119901minus1119901
1)10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
1199021
)
11199021
le 119862(sum
119895isinZ
(211989511990410038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
1199021
)
11199021
le 11986210038171003817100381710038171198911003817100381710038171003817B119904120573
119901119902(R119889+1+
)
(57)
since 119902 le 1199021 This gives the inclusion
Proposition 21 (1) If 119906 belongs to B119904120573
119901119902(R119889+1
+) cap
B119905120573
119901119902(R119889+1
+)
then 119906 belongs to B120579119904+(1minus120579)119905120573
119901119902 (R119889+1
+) for all 120579 isin [0 1] and
119906B120579119904+(1minus120579)119905120573
119901119902(R119889+1+
)le 119906
120579
B119904120573
119901119902(R119889+1+
)119906
1minus120579
B119905120573
119901119902(R119889+1+
) (58)
(2) If 119906 belongs to B119904120573
119901infin(R119889+1
+) cap
B119905120573
119901infin(R119889+1
+) and 119904 lt 119905
then 119906 belongs to B120579119904+(1minus120579)119905120573
1199011(R119889+1
+) for all 120579 isin (0 1) and there
exists a positive constant 119862(119905 119904) such that
119906B120579119904+(1minus120579)119905120573
1199011(R119889+1+
)le 119862 (119905 119904) 119906
120579
B119904120573
119901infin(R119889+1+
)119906
1minus120579
B119905120573
119901infin(R119889+1+
) (59)
(3) If 119906 belongs to B119904120573
119901infin(R119889+1
+) cap
B119904+120576120573
119901infin (R119889+1
+) and 120576 gt
0 then 119906 belongs to B119904120573
1199011(R119889+1
+) and there exists a positive
constant 119862 such that
119906B119904120573
1199011(R119889+1+
)le
119862
120576
119906B119904120573
119901infin(R119889+1+
)log
2(119890 +
119906B119904+120576120573
119901infin(R119889+1+
)
119906B119904120573
119901infin(R119889+1+
)
)
(60)
Proof (1) is obvious from the Holderrsquos inequality As for (2)we write 119906
B120579119904+(1minus120579)119905120573
1199011(R119889+1+
)as
sum
119895le119873
2119895(120579119904+(1minus120579)119905)10038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)+ sum
119895gt119873
2119895(120579119904+(1minus120579)119905)10038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
(61)
where 119873 is chosen here after By the definition of thehomogeneous Weinstein-Besov norms we see that
2119895(120579119904+(1minus120579)119905)10038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 2
119895(1minus120579)(119905minus119904)119906
B119904120573
119901infin(R119889+1+
)
2119895(120579119904+(1minus120579)119905)10038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 2
minus119895120579(119905minus119904)119906
B119905120573
119901infin(R119889+1+
)
(62)
and thus 119906B120579119904+(1minus120579)119905120573
1199011(R119889+1+
)is dominated by
119906B119904120573
119901infin(R119889+1+
)sum
119895le119873
2119895(1minus120579)(119905minus119904)
+ 119906B119905120573
119901infin(R119889+1+
)sum
119895gt119873
2minus119895120579(119905minus119904)
le 119862119906B119904120573
119901infin(R119889+1+
)
2(119873+1)(1minus120579)(119905minus119904)
2(1minus120579)(119905minus119904)
minus 1
+ 119906B119905120573
119901infin(R119889+1+
)
2minus119873120579(119905minus119904)
1 minus 2minus120579(119905minus119904)
(63)
Hence in order to complete the proof of (2) it suffices tochoose119873 such that
119906B119905120573
119901infin(R119889)
119906B119904120573
119901infin(R119889)
le 2119873(119905minus119904)
lt 2
119906B119905120573
119901infin(R119889)
119906B119904120573
119901infin(R119889)
(64)
As for (3) it is easy to see that 119906B119904120573
1199011(R119889+1+
)is dominated as
sum
119895le119873minus1
211989511990410038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)+ sum
119895ge119873
211989511990410038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
le (119873 + 1) 119906B119904120573
119901infin(R119889+1+
)+
2minus(119873minus1)120576
2120576minus 1
119906B119904+120576120573
119901infin(R119889+1+
)
(65)
Hence letting
119873 = 1 + [
[
1
120576
log2
119906B119904+120576120573
119901infin(R119889+1+
)
119906B119904120573
119901infin(R119889+1+
)
]
]
(66)
we can obtain the desired estimate
Proposition 22 Let 119902 isin (1infin) and let 119904 isin R such that0 lt 119904 lt (119889 + 2120573 + 2)119902 then one has
B119904120573
119902119902(R
119889+1
+) =
F119904120573
119902119902(R
119889+1
+) 997893rarr
F119904120573
119902infin(R
119889+1
+)
997893rarrF119904minus((119889+2120573+2)119902)120573
infininfin(R
119889+1
+)
(67)
H119904
119902120573(R
119889+1
+) =
F119904120573
1199022(R
119889+1
+) 997893rarr
F119904120573
119902infin(R
119889+1
+)
997893rarrF119904minus((119889+2120573+2)119902)120573
infininfin(R
119889+1
+)
(68)
Proof We obtain these results by the similar ideas used in thenonhomogeneous case (cf [6])
Theorem 23 Let 119886 119887 gt 0 and let 1199021 1199022 isin [1infin] Let120579 = 119886(119886 + 119887) isin (0 1) and let 1119901 = (1 minus 120579)1199021 +
1205791199022 Then there exists a constant 119862 such that for every119891 isin
F119886120573
1199021infin(R119889+1
+) cap
Fminus119887120573
1199022infin(R119889+1
+) then one has
1003816100381610038161003816119891 (119909)
1003816100381610038161003816le 119862(sup
119895isinZ
2119886119895 10038161003816100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
1minus120579
(sup119895isinZ
2minus119887119895 10038161003816
100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
120579
(69)
In particular one gets
10038171003817100381710038171198911003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
10038171003817100381710038171198911003817100381710038171003817
1minus120579
F119886120573
1199021infin(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
120579
Fminus119887120573
1199022infin(R119889+1+
) (70)
Journal of Function Spaces and Applications 7
Proof Let 119891 be a Schwartz class we have
1003816100381610038161003816119891 (119909)
1003816100381610038161003816le sum
119895isinZ
10038161003816100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816
le sum
119895isinZ
min(2minus119886119895sup119895isinZ
(2119886119895 10038161003816100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
2119895119887sup119895isinZ
(2minus119895119887 10038161003816
100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816))
(71)
We define119873(119909) as the largest index such that
2119895119887sup119895isinZ
(2minus119895119887 10038161003816
100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816) le 2
minus119886119895sup119895isinZ
(2119886119895 10038161003816100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816) (72)
and we write1003816100381610038161003816119891 (119909)
1003816100381610038161003816le sum
119895le119873(119909)
2119895119887sup119895isinZ
(2minus119895119887 10038161003816
100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
+ sum
119895gt119873(119909)
2minus119886119895sup
119895
(2119886119895 10038161003816100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
le 119862(sup119895isinZ
2119886119895 10038161003816100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
119887(119886+119887)
times (sup119895isinZ
2minus119887119895 10038161003816
100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
119886(119886+119887)
(73)
Thus (69) is proved In order to obtain (70) it is enough toapply the Holder inequality in the expression above since wehave 120579 = 119886(119886+119887) isin (0 1) and let 1119901 = (1minus120579)1199021+1205791199022
Corollary 24 Let 119902 isin (1infin) and let 119904 isin R such that 0 lt 119904 lt
(119889 + 2120573 + 2)119902 then one has
10038171003817100381710038171198911003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
10038171003817100381710038171198911003817100381710038171003817
1minus(119902119901)
Bminus((2120573+2+119889)119902minus119904)120573
infininfin (R119889+1
+ )
10038171003817100381710038171198911003817100381710038171003817
119902119901
B119904120573
119902119902(R119889+1
+ )
(74)
10038171003817100381710038171198911003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
10038171003817100381710038171198911003817100381710038171003817
1minus(119902119901)
Bminus((2120573+2+119889)119902minus119904)120573
infininfin (R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
119902119901
H119904119902120573(R119889+1+
) (75)
where 119901 = 119902(2120573 + 2 + 119889)(2120573 + 2 + 119889 minus 119902119904)
Proof By choosing 119886 = 119904 gt 0 minus119887 = 119904 minus (119889 + 2120573 + 2)119902 lt 01199021 = 119902 and 1199022 = infin we deduce (74) from the relations (70)and (67) In the same way we deduce (75) from the relations(70) and (68)
4 Generalized Heat Equation
41 Characterization for the Weinstein-Besov Spaces TheWeinstein heat equation reads
120597119905119906 (119905 119909) minus Δ 120573119906 (119905 119909) = 119891 (119905 119909) (119905 119909) isin [0infin) timesR119889+1
+
119906|119905=0 = 119892
(76)
We introduce the Weinstein heat semigroup 119867120573(119905) for theWeinstein-Laplace operator
119867120573 (119905) 119892 (119909) =
int
R119889+1+
Γ120573 (119905 119909 119910) 119892 (119910) 119889120583120573 (119910) if 119905 gt 0
119892 (119909) if 119905 = 0(77)
where Γ120573 is the Weinstein heat kernel defined by
Γ120573 (119905 119909 119910) = 120591119909 (119864(120573)
119905) (119910) (78)
where
119864(120573)
119905(119910) =
2
1205871198892Γ (120573 + 1) (4119905)
120573+1+1198892119890minus11991024119905 (79)
Thus
119867120573 (119905) 119892 (119909) = 119892lowast119882119864(120573)
119905 (119909) (80)
In practice we use the integral formulation of (76)
119906 (119905 119909) = 119867120573 (119905) 119892 (119909) + 119866120573 (119891) (119905 119909)
= 119867120573 (119905) 119892 (119909) + int
119905
0
119867120573 (119905 minus 119904) 119891 (119904 119909) 119889119904
(81)
Remark 25 The function 119864(120573)119905
is the Gauss kernel associatedwith Weinstein operators This function satisfies
forall120585 isin R119889+1
+ F119882 (119864
(120573)
119905) (120585) = 119890
minus1199051205852
(82)
Proposition 26 Let 1 le 119901 le 119903 le infin and let 119891 isin 119871119901
120573(R119889+1
+)
Then the operator 119867120573(119905) maps 119871119901
120573(R119889+1
+) continuously to
119871119903
120573(R119889+1
+) and
10038171003817100381710038171003817119867120573 (119905) 119891
10038171003817100381710038171003817119871119903120573(R119889)
le 119862119905minus((119889+2120573+2)2)(1119901minus1119903)1003817
1003817100381710038171198911003817100381710038171003817119871119901
120573(R119889)
(83)
Moreover1003817100381710038171003817100381710038171003817
(minusΔ 120573)
1205752
119867120573 (119905) 119891
1003817100381710038171003817100381710038171003817119871119903120573(R119889)
le 119862119905minus1205752minus((119889+2120573+2)2)(1119901minus1119903)1003817
1003817100381710038171198911003817100381710038171003817119871119901
120573(R119889)
(84)
for all 120575 gt 0
Proof It follows from the relations (80) and (29) combinedwith scaling property of the kernel 119864(120573)
119905
In this section we prove estimates for the Weinstein heatsemigroupThese estimates are based on the following result
Lemma 27 Let C be an annulus Positive constants 119888 and 119862exist such that for any 119901 in [1infin] and any couple (119905 120582) ofpositive real numbers one has
suppF119882 (119906) sub 120582C 997904rArr
10038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
le 119862119890minus1198881199051205822
119906119871119901
120573(R119889+1+
)
(85)
8 Journal of Function Spaces and Applications
Proof We again consider a function Θ in 119863(R119889+1
+ 0) the
value of which is identically 1 in neighborhood of annulusCWe can also assume without loss of generality that 120582 = 1 Wethen have
119867120573 (119905) 119906 = 119892 (119905 sdot) lowast119882119906 (86)where
119892 (119905 sdot) = Fminus1
119882(Θ (120585) 119890
minus1199051205852
) (87)
The lemma is proved provided that we can find positive realnumbers 119888 and 119862 such that
forall119905 gt 01003817100381710038171003817119892 (119905 sdot)
10038171003817100381710038171198711120573(R119889+1+
)le 119862119890
minus119888119905 (88)
To begin we perform integrations by parts in (87) We get1003816100381610038161003816119892 (119905 119909)
1003816100381610038161003816=
1
119888120573
(1 + 1199092)
minus(119889+[2120573]+3)
times int
R119889+1+
Λ (119909 120585) (119868119889 minus Δ 120573)
119889+[2120573]+3
times (Θ (120585) 119890minus1199051205852
) 119889120583120573 (120585)
(89)
Using Leibnizrsquos formula we obtain1003816100381610038161003816119892 (119905 119909)
1003816100381610038161003816le 119862(1 + 119909
2)
minus(119889+[2120573]+3)
119890minus119888119905 (90)
and (88) follows
For any interval 119868 of R (bounded or unbounded) wedefine themixed space-time 119871119901(119868 119871119902
120573(R119889+1
+)) Banach space of
(classes of) measurable functions 119906 119868 rarr 119871119902
120573(R119889+1
+) such
that 119906119871119901(119868119871
119902
120573(R119889+1+
))lt infin with
119906119871119901(119868119871119902
120573(R119889+1+
))= (int
119868
119906 (119905 sdot)119901
119871119902
120573(R119889+1+
)119889119905)
1119901
if 1 le 119901 119902 lt infin
119906119871infin(119868119871119902
120573(R119889+1+
))= ess sup
119905isin119868
119906 (119905 sdot)119871119902
120573(R119889+1+
) if 1 le 119902 lt infin
(91)Corollary 28 Let C be an annulus and 120582 a positive realnumber Let 1199060 (resp 119891 = 119891(119905 119909)) satisfy suppF119882(1199060) sub 120582C(resp suppF119882(119891(119905 sdot)) sub 120582C for all 119905 in [0 119879]) Consider 119906 asolution of
120597119905119906 minus Δ 120573119906 = 0 119906|119905=0 = 1199060 (92)and V a solution of
120597119905V minus Δ 120573V = 119891 (119905 sdot) V|119905=0 = 0 (93)There exist positive constants 119888 and 119862 depending only on Csuch that for any 1 le 119886 le 119887 le infin and 1 le 119901 le 119902 le infin we have
119906119871119902([0119879]119871119887120573(R119889+1+
))le 119862120582
(119889+2120573+2)(1119886minus1119887)120582minus21199021003817
1003817100381710038171199060
1003817100381710038171003817119871119886120573(R119889+1+
)
V119871119902([0119879]119871119887120573(R119889+1+
))le 119862120582
minus2(1+1119902minus1119901)120582(119889+2120573+2)(1119886minus1119887)
times10038171003817100381710038171198911003817100381710038171003817119871119901([0119879]119871119886
120573(R119889+1+
))
(94)
Proof It suffices to use the fact that
119906 (119905 sdot) = 119867120573 (119905) 1199060 V (119905 sdot) = int119905
0
119867120573 (119905 minus 119904) 119891 (119904 sdot) 119889119904
(95)
Combining Lemma 27 and Youngrsquos inequality (29) withscaling property of the kernel 119864(120573)
119905now yields the result
Theorem 29 Let 119904 be a positive real number and (119901 119903) isin
[1infin]2 A constant 119862 exists which satisfies the following
property For 119906 isin Bminus2119904120573
119901119903 (R119889+1
+) one has
119862minus1119906
Bminus2119904120573
119901119903(R119889+1+
)le
10038171003817100381710038171003817100381710038171003817
10038171003817100381710038171003817119905119904119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
10038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
le 119862119906Bminus2119904120573
119901119903(R119889+1+
)
(96)
To prove this result we need the following lemma
Lemma 30 There exist two positive constants 120581 and 119862
depending only on 120593 such that for all 1 le 119901 le infin 120591 ge 0 and119895 isin Z one has
10038171003817100381710038171003817Δ 119895 (119867120573 (120591) 119906)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862119890
minus1205812211989512059110038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
) (97)
Proof The result follows immediately by applying Lemma 27and because Δ 119895(119867120573(120591))119906 = (119867120573(120591)Δ 119895)119906
Proof of Theorem 29 Using Lemma 30 and considering thefact that the operator Δ 119895 commutes with the operator 119867120573(119905)
and the definition of the homogeneous Weinstein-Besov(semi) norm we get
10038171003817100381710038171003817119905119904119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862119906
Bminus2119904120573
119901119903(R119889+1+
)sum
119895isinZ
11990511990422119895119904119890minus12058111990522119895
119888119903119895
(98)
where (119888119903119895)119895isinZ denotes as in all this proof a generic elementof the unit sphere of 119897119903(Z) In the case when 119903 = infin therequired inequality comes immediately from the followingeasy result For any positive 119904 we have
sup119905gt0
sum
119895isinZ
11990511990422119895119904119890minus12058111990522119895
lt infin (99)
In the case 119903 lt infin using the Holder inequality with theweight 22119895119904119890minus1205811199052
2119895
(99) and the Fubini theorem we obtain
int
infin
0
11990511990311990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)
119889119905
119905
le 119862119906119903
Bminus2119904120573
119901119903(R119889+1+
)int
infin
0
(sum
119895isinZ
11990511990422119895119904119890minus12058111990522119895
)
119903minus1
times (sum
119895isinZ
11990511990422119895119904119890minus12058111990522119895
119888119903
119903119895)
119889119905
119905
Journal of Function Spaces and Applications 9
le 119862119906119903
Bminus2119904120573
119901119903(R119889+1+
)int
infin
0
(sum
119895isinZ
11990511990422119895119904119890minus12058111990522119895
119888119903
119903119895)
119889119905
119905
le 119862119906119903
Bminus2119904120573
119901119903(R119889+1+
)sum
119895isinZ
119888119903
119903119895int
infin
0
(11990511990422119895119904119890minus12058111990522119895
)
119889119905
119905
le 119862Γ (119904) 119906119903
Bminus2119904120573
119901119903(R119889+1+
)
(100)
In order to prove the other inequality let us observe thatfor any 119904 greater than minus1 we have
Δ 119895119906 =
1
Γ (119904 + 1)
int
infin
0
119905119904(minusΔ 120573)
119904+1
119867120573 (119905) Δ 119895119906 119889119905 (101)
Then Lemma 30 Proposition 9 and the fact that the operatorΔ 119895 commutes with the operator119867120573(119905) lead to the following
10038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862int
infin
0
11990511990422119895(119904+1)
119890minus1205811199052211989510038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889119905
(102)
In the case 119903 = infin we simply write
10038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862(sup
119905gt0
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
times int
infin
0
22119895(119904+1)
119890minus12058111990522119895
119889119905
le 11986222119895119904(sup119905gt0
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
(103)
In the case 119903 lt infin Holderrsquos inequality with the weight 119890minus12058111990522119895
gives
(int
infin
0
119905119904119890minus1205811199052211989510038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889119905)
119903
le 1198622minus2119895(119903minus1)
int
infin
0
119905119903119904119890minus1205811199052211989510038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)119889119905
(104)
Thanks to (99) and Fubinirsquos theorem we infer from (102) that
sum
119895isinZ
2minus211989511990311990410038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)le 119862int
infin
0
11990511990311990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)
119889119905
119905
(105)
The theorem is proved
Second Proof ofTheorem 29We only consider the case 1 le 119903 ltinfinThe case 119903 = infin can be shown similarlyWe first prove that
119862minus1119906
Bminus2119904120573
119901119903(R119889+1+
)le
10038171003817100381710038171003817100381710038171003817
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
10038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
(106)
It is easy to see that
Δ 119895119906 = 120594119895lowast119882119864(120573)
2minus2119895lowast119882119906
(107)
where 120594119895 = Fminus1
119882(120593(2
minus119895120585)119890
2minus21198951205852
) and119864(120573)2minus2119895
is the Gauss kernelassociated with Weinstein operators By relation (29) we get
10038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le
10038171003817100381710038171003817120594119895
100381710038171003817100381710038171198711120573(R119889+1+
)
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
) (108)
As10038171003817100381710038171003817120594119895
100381710038171003817100381710038171198711120573(R119889+1+
)= int
R119889+1+
100381610038161003816100381610038161003816F
minus1
119882(120593 (120585) 119890
1205852
)
100381610038161003816100381610038161003816119889120583120573 (120585) lt infin (109)
we obtain10038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
) (110)
Moreover simple calculations give that
119864(120573)
2minus2119895lowast119882119906 = 119867120573 (2
minus4119895minus 119905
2) (119864
(120573)
1199052lowast119882119906)
(111)
Thus from Proposition 26 it follows that100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
100381710038171003817100381710038171003817119864(120573)
1199052lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1
+ )
(112)
for any 119905 isin [2minus119895minus1 2minus119895] which implies that
sum
119895isinZ
2minus211990411989511990310038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)
le 119862 sum
119895isinZ
int
2minus119895
2minus119895minus1(119905
2119904100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903119889119905
119905
le 119862int
infin
0
(1199052119904100381710038171003817100381710038171003817119864(120573)
1199052lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903119889119905
119905
le 119862int
infin
0
(11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903119889119905
119905
(113)
where we have used the fact that 119864(120573)1199052lowast119882119906 = 119867120573(119905
2)119906
We now prove that10038171003817100381710038171003817100381710038171003817
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
10038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
le 119862119906Bminus2119904120573
119901119903(R119889+1+
) (114)
Indeed one has
119864(120573)
2minus2119895lowast119882119906 = sum
119899isinZ
119864(120573)
2minus2119895lowast119882Δ 119899+119895119906 (115)
Arguing as above we have100381710038171003817100381710038171003817119864(120573)
1199052lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1
+ )
(116)
for any 119905 isin [2minus119895 21minus119895] Thus10038171003817100381710038171003817100381710038171003817
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
10038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
= 2
100381710038171003817100381710038171003817100381710038171003817
1003817100381710038171003817100381710038171199052119904119864(120573)
1199052lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)
100381710038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
le 119862 sum
119895isinZ
int
21minus119895
2minus119895(2
minus2119895119904100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903119889119905
119905
le 119862 sum
119895isinZ
(2minus2119895119904
sum
119899isinZ
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
(117)
10 Journal of Function Spaces and Applications
On the other hand it is easy to see that100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)le 1198622
minus211989911990410038171003817100381710038171003817Δ 119899+119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
) (118)
for any 119904 gt 0 For 0 lt 1199041 lt 119904 lt 1199042 and by using theMinkowskiinequality we have
sum
119895isinZ
(2minus2119895119904
sum
119899isinZ
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
le sum
119895isinZ
(2minus2119895119904
0
sum
minusinfin
2minus21198991199041
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
+ sum
119895isinZ
(2minus2119895119904
sum
119899isinN
2minus21198991199042
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
le 119862(
0
sum
minusinfin
2minus2119899(119904
1minus119904)(sum
119895isinZ
(2minus2(119899+119895)11990311990410038171003817
100381710038171003817Δ 119899+119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
)
1119903
)
119903
+ 119862(sum
N
2minus2119899(119904
2minus119904)(sum
119895isinZ
(2minus2(119899+119895)11990311990410038171003817
100381710038171003817Δ 119899+119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
)
1119903
)
119903
le 119862 sum
119895isinZ
2minus211989511990311990410038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)
(119)
The result is immediately from (117) and (119)
42 Embedding Sobolev Theorems
Theorem 31 Let 1 lt 119901 lt infin and let 0 lt 119904 lt (119889 + 2120573 +
2)119901There exists a positive constant119862 such that for all function119891 isin
H119904
119901120573(R119889+1
+) one has
10038171003817100381710038171198911003817100381710038171003817119871119902
120573(R119889+1+
)le 119862
10038171003817100381710038171198911003817100381710038171003817
1minus120579
H119904119901120573(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
120579
B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
) (120)
where 120579 = 119904119901(119889+2120573+2) and 119902 = 119901(119889+2120573+2)(119889+2120573+2minus119901119904)
Proof Bydensity we can suppose that119891belongs toSlowast(R119889+1
)It is easy to see that
119891 = int
infin
0
119867120573 (119905) Δ 120573119891119889119905(121)
and decompose the integral in two parts as follows
119891 = int
119860
0
119867120573 (119905) Δ 120573119891119889119905 + int
infin
119860
119867120573 (119905) Δ 120573119891119889119905(122)
where 119860 is a constant to be fixed laterOn the other hand byTheorem 29 we obtain10038171003817100381710038171003817119867120573 (119905) Δ 120573119891
10038171003817100381710038171003817119871infin120573(R119889+1+
)
le
119862
1199051minus(12)(119904minus(119889+2120573+2)119901)
10038171003817100381710038171198911003817100381710038171003817B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
)
(123)
Therefore after integrating we get
int
infin
119860
10038171003817100381710038171003817119867120573 (119905) Δ 120573119891
10038171003817100381710038171003817119871infin120573(R119889+1+
)119889119905
le 119860(12)(119904minus(119889+2120573+2)119901)1003817
1003817100381710038171198911003817100381710038171003817B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
)
(124)
On the other hand denoting 119892 = (minusΔ 120573)1199042119891 we have
119867120573 (119905) Δ 120573119891 =
1
(minus119905)1minus1199042
119867120573 (119905) (minus119905Δ 120573)
1minus1199042
119892 (125)
We proceed as in [8] we prove that1003816100381610038161003816100381610038161003816
119867120573 (119905) (minus119905Δ 120573)
1minus1199042
119892 (119909)
1003816100381610038161003816100381610038161003816
le 119862 (119904)119872120573 (119892) (119909) (126)
where119872120573(119892) is a maximal function of 119892 associated with theWeinstein operators (cf [12])
This leads to100381610038161003816100381610038161003816100381610038161003816
int
119860
0
119867120573 (119905) Δ 120573119891 (119909) 119889119905
100381610038161003816100381610038161003816100381610038161003816
le 1198621198601199042119872120573 (119892) (119909) (127)
In conclusion we get10038161003816100381610038161003816100381610038161003816
int
infin
0
119867120573 (119905) Δ 120573119891 (119909) 119889119905
10038161003816100381610038161003816100381610038161003816
le 119862 (1198601199042119872120573 (119892) (119909)
+119860(12)(119904minus(119889+2120573+2)119901)1003817
1003817100381710038171198911003817100381710038171003817B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
))
(128)
and the choice of 119860 such that
119860(119889+2120573+2)2119901
119872120573 (119892) (119909) =10038171003817100381710038171198911003817100381710038171003817B119904minus(119889+2120573+2)119901120573
infininfin (R119889+1+
)(129)
ensures that10038161003816100381610038161003816100381610038161003816
int
infin
0
119867120573 (119905) Δ 120573119891 (119909) 119889119905
10038161003816100381610038161003816100381610038161003816
le 119862(119872120573(119892)(119909))
1minus(119901119904(119889+2120573+2))10038171003817100381710038171198911003817100381710038171003817
119901119904(119889+2120573+2)
B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
)
(130)
Finally taking the 119871119902120573norm with 119902 = 119901(119889 + 2120573 + 2)(119889 + 2120573 +
2minus119901119904) ends the proof thanks to the fact themaximal function119872120573 is bounded of 119871119902
120573(R119889+1
+) into itself for 119902 gt 1
Theorem 32 Let 1 lt 119901 lt 119902 lt infin For all function 119891 such that119891 isin
H1199041
119901120573(R119889+1
+)⋂
Bminus120573120573
infininfin(R119889+1
+) one has
10038171003817100381710038171198911003817100381710038171003817H119904119901120573(R119889+1+
)le 119862
10038171003817100381710038171198911003817100381710038171003817
120579
H1199041
119901120573(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
1minus120579
Bminus120573120573
infininfin(R119889+1
+) (131)
where 120579 = 119901119902 119904 = 1205791199041 minus (1 minus 120579)120573 with 120573 gt 0 minus120573 lt 119904 lt 1199041
Proof It suffices to prove that1003817100381710038171003817100381710038171003817
(minusΔ 120573)
(119904minus1199041)2
119891
1003817100381710038171003817100381710038171003817119871119902
120573(R119889+1+
)
le 11986210038171003817100381710038171198911003817100381710038171003817
120579
119871119901
120573(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
1minus120579
Bminus120573minus1199041120573
infininfin (R119889+1+
)
(132)
Journal of Function Spaces and Applications 11
Indeed we use the following identity (which may be easilyproven by taking the Weinstein transform in 119909 of both sides)
(minusΔ 120573)
minus1205752
119891 (119909) =
1
Γ (1205752)
int
infin
0
1199051205752minus1
119867120573 (119905) 119891 (119909) 119889119905 (133)
with 120575 = 1199041 minus 119904 gt 0We decompose the integral in two parts as follows
(minusΔ 120573)
minus1205752
119891 (119909) =
1
Γ (1205752)
int
119879
0
1199051205752minus1
119867120573 (119905) 119891 (119909) 119889119905
+
1
Γ (1205752)
int
infin
119879
1199051205752minus1
119867120573 (119905) 119891 (119909) 119889119905
(134)
where 119879 is a constant to be fixed laterWe proceed as in [8] we obtain
10038161003816100381610038161003816119867120573 (119905) 119891 (119909)
10038161003816100381610038161003816le 119862119872120573 (119891) (119909) (135)
On the other hand we use Theorem 29 and the fact that 119891belongs to Bminus120573minus119904
1120573
infininfin(R119889+1
+) to deduce that
10038161003816100381610038161003816119867120573 (119905) 119891 (119909)
10038161003816100381610038161003816le 119862119905
(minus120573minus1199041)210038171003817100381710038171198911003817100381710038171003817Bminus120573minus1199041120573
infininfin (R119889+1+
) (136)
Thus by applying the preceding estimates on the right part of(134) we obtain
1003816100381610038161003816100381610038161003816
(minusΔ 120573)
minus1205752
119891 (119909)
1003816100381610038161003816100381610038161003816
le
1198621
Γ (1205752)
1198791205752119872120573 (119891) (119909)
+
1198622
Γ (1205752)
119879(120575minus120573minus119904
1)210038171003817100381710038171198911003817100381710038171003817Bminus120573minus1199041120573
infininfin (R119889+1+
)
(137)
We fix now
119879 = (
10038171003817100381710038171198911003817100381710038171003817Bminus120573minus1199041120573
infininfin (R119889+1+
)
119872120573 (119891) (119909)
)
2(120573+1199041)
(138)
We obtain
1003816100381610038161003816100381610038161003816
(minusΔ120573)
minus1205752
119891 (119909)
1003816100381610038161003816100381610038161003816
le
1198621 + 1198622
Γ (1205752)
(119872120573(119891)(119909))
12057910038171003817100381710038171198911003817100381710038171003817
1minus120579
Bminus120573minus1199041120573
infininfin (R119889+1+
)
(139)
Thus we deduce that1003817100381710038171003817100381710038171003817
(minusΔ120573)
minus1205752
119891
1003817100381710038171003817100381710038171003817119871119902
120573(R119889+1+
)
le
1198621 + 1198622
Γ (1205752)
10038171003817100381710038171003817119872120573 (119891)
10038171003817100381710038171003817
120579
119871119901
120573(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
1minus120579
Bminus120573minus1199041120573
infininfin (R119889+1+
)
(140)
To conclude we used the fact that the maximal function119872120573
is bounded of 119871119902120573(R119889+1
+) into itself for 119902 gt 1
43 Estimates in Generalized Besov Spaces For any interval 119868ofR (bounded or unbounded) and a normed space 119865(R119889+1
+)
we define the mixed space-time 119871119901(119868 119865(R119889+1
+)) space of
(classes of) measurable functions 119906 119868 rarr 119865(R119889+1
+) such that
||119906||119871119901(119868119865(R119889+1+
)) lt infin with
119906119871119901(119868119865(R119889+1+
)) = (int
119868
119906 (119905 sdot)119901
119865(R119889+1+
)119889119905)
1119901
if 1 le 119901 lt infin
119906119871infin(119868119865(R119889+1+
)) = ess sup119905isin119868
119906 (119905 sdot)119865(R119889+1+
)
(141)
For any interval 119868 of R (bounded or unbounded) anda Banach space 119883 we define the mixed space-time 119862(119868119883)space of continuous functions 119868 rarr 119883 When 119868 is bounded119862(119868119883) is a Banach space with the norm of 119871infin(119868 119883)
Theorem 33 Let 119904 isin R and 1 le 119901 119902 119903 le infin Let 119879 gt 0 119892 isin
B119904120573
119901119903(R119889+1
+) and119891 in 119871119902((0 119879) B
119904minus2+(2119902)120573
119901119903 (R119889+1
+)) Then (76)
has a unique solution
119906 isin 119871119902((0 119879)
B119904+(2119902)120573
119901119903(R
119889+1
+))
⋂119871infin((0 119879)
B119904120573
119901119903(R
119889+1
+))
(142)
and there exists a constant 119862 such that for all 1199021 isin [119902infin] onehas
1199061198711199021 ((0119879)B
119904+(21199021)120573
119901119903(R119889+1+
))
le 119862(10038171003817100381710038171198921003817100381710038171003817B119904120573
119901119903(R119889+1+
)+10038171003817100381710038171198911003817100381710038171003817119871119902((0119879)B
119904minus2+(2119902)120573
119901119903(R119889+1+
)))
(143)
If in addition 119903 lt infin then 119906 isin 119862([0 119879] B119904120573
119901119903(R119889+1
+))
Proof Since 119892 and 119891 are temperate distributions (76) has aunique solution 119906 in S1015840
((0 119879) timesR119889+1
+) which satisfies
F119882 (119906) (119905 120585) = 119890minus1199051205852
F119882 (119892) (120585)
+ int
119905
0
119890(120591minus119905)120585
2
F119882 (119891) (120591 120585) 119889120591
(144)
Next we notice that applying Δ 119895 to (76) and using formula(81) yield
Δ 119895119906 (119905 sdot) = 119867120573 (119905) Δ 119895119892 + int
119905
0
119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot) 119889120591(145)
Therefore
10038171003817100381710038171003817Δ 119895119906 (119905 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le
10038171003817100381710038171003817119867120573(119905)Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+ int
119905
0
10038171003817100381710038171003817119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591
(146)
12 Journal of Function Spaces and Applications
By virtue of Lemma 30 we thus have for some 120581 gt 0
10038171003817100381710038171003817Δ 119895119906(119905 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
le 119862[119890minus1205812211989511990510038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+ int
119905
0
119890minus12058122119895(119905minus120591) 10038171003817
100381710038171003817Δ 119895119891 (120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591]
(147)
Applying convolution inequalities we get
10038171003817100381710038171003817Δ 119895119906
100381710038171003817100381710038171198711199021 ((0119879)119871
119901
120573(R119889+1+
))
le 119862[
[
((
1 minus 119890minus120581119879119902122119895
120581119902122119895
)
11199021
)
10038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+((
1 minus 119890minus120581119879119902222119895
120581119902222119895
)
11199022
)
10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119902((0119879)119871
119901
120573(R119889+1+
))
]
]
(148)
with 11199022 = 1+ 11199021 minus1119902 Finally taking the 119897119903(Z) norm we
conclude that (with the usual convention if 119903 = infin)
1199061198711199021 ((0119879)B
119904+(21199021)120573
119901119903(R119889+1+
))
le 119862[
[
sum
119895isinZ
((
1 minus 119890minus120581119879119902122119895
120581119902122119895
)
1199031199021
)(211989511990410038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
]
]
1119903
+ 119862[
[
sum
119895isinZ
((
1 minus 119890minus120581119879119902222119895
120581119902222119895
)
1199031199022
)
times (2119895(119904minus2+2119902)10038171003817
100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119902(0119879119871
119901
120573(R119889+1+
))
119903
]
]
1119903
(149)
which insures that 119906 isin 119871119902((0 119879)
B119904+(2119902)120573
119901119903 (R119889+1
+))
⋂119871infin((0 119879)
B119904120573
119901119903(R119889+1
+)) and yields the desired inequality
Since 119906 belongs to 119862([0 119879]B119904120573
119901119903(R119889+1
+)) in the case where
119903 is finite may be easily deduced from the density ofSlowast(R
119889+1)⋂
B119904120573
119901119903(R119889+1
+) in B
119904120573
119901119903(R)
Theorem 34 Let 119904 isin R 119879 gt 0 and 1 le 119901 119902 119903 le infinOne supposes that 119892 isin 119861
119904120573
119901119903(R119889+1
+) and 119891 isin 119871
119902((0 119879)
119861119904minus2+(2119902)120573
119901119903 (R119889+1
+)) Then (76) has a unique solution 119906 belong-
ing to
119871119902((0 119879) 119861
119904+(2119902)120573
119901119903(R
119889+1
+))⋂119871
infin((0 119879) 119861
119904120573
119901119903(R
119889+1
+))
(150)
and there exists a constant 119862 such that for all 119902 le 1199021 le infin
1199061198711199021 ((0119879)119861
119904+(21199021)120573
119901119903(R119889+1+
))
le 119862 [ (1 + 11987911199021)10038171003817100381710038171198921003817100381710038171003817119861119904120573
119901119903(R119889+1+
)
+ (1 + 1198791+1119902
1minus1119902
)10038171003817100381710038171198911003817100381710038171003817119871119902((0119879)119861
119904minus2+(2119902)120573
119901119903(R119889+1+
))]
(151)
If in addition 119903 lt infin then 119906 isin 119862([0 119879] 119861119904120573119901119903(R119889+1
+))
Proof Since 119892 119891 are tempered (76) has a unique solution 119906in S1015840
((0 119879) timesR119889+1
+) satisfying
F119882 (119906) (119905 120585) = 119890minus1199051205852
F119882 (119892) (120585)
+ int
119905
0
119890(120591minus119905)120585
2
F119882 (119891) (120591 120585) 119889120591
(152)
Hence applying Δ 119895 119895 ge 0 to (81) we see that
Δ 119895119906 (119905 sdot) = 119867120573 (119905) Δ 119895119892 + int
119905
0
119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot) 119889120591(153)
and thus by Lemma 30 we can deduce that10038171003817100381710038171003817Δ 119895119906 (119905 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
le
10038171003817100381710038171003817119867120573(119905)Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)+ int
119905
0
10038171003817100381710038171003817119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591
le 119862[119890minus1205812211989511990510038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+int
119905
0
119890minus12058122119895(119905minus120591)10038171003817
100381710038171003817Δ 119895119891(120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591]
(154)
Then it follows from convolution inequalities thatΔ 1198951199061198711199021 ((0119879)119871
119901
120573(R119889+1+
))is dominated by
(
1 minus 119890minus120581119879119902122119895
120581119902122119895
)
11199021
10038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119861119904120573
119901119903(R119889+1+
)
+ (
1 minus 119890minus120581119879119902222119895
120581119902222119895
)
11199022
10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119902((0119879)119871
119901
120573(R119889+1+
))
(155)
with 11199022 = 1 + 11199021 minus 1119902 Moreover similarly as above wecan obtain that
1003817100381710038171003817Δminus1119906(119905 sdot)
1003817100381710038171003817119871119901
120573(R119889+1+
)le1003817100381710038171003817Δminus1119892
1003817100381710038171003817119871119901
120573(R119889+1+
)
+ int
119905
0
1003817100381710038171003817Δminus1119891 (120591 sdot)
1003817100381710038171003817119871119901
120573(R119889+1+
)119889120591
(156)
and thus if 1 le 119902 le 1199021 le infin1003817100381710038171003817Δminus1119906
10038171003817100381710038171198711199021 ((0119879)119871
119901
120573(R119889+1+
))
le 119862(119879111990211003817100381710038171003817Δminus1119892
1003817100381710038171003817119871119901
120573(R119889+1+
)+ 119879
111990221003817100381710038171003817Δminus1119891
1003817100381710038171003817119871119902((0119879)119871
119901
120573(R119889+1+
)))
(157)
Journal of Function Spaces and Applications 13
Finally taking the 119897119903-normwith respect to 119895 in (155) and (157)with the usual convention if 119903 = infin we can deduce the desiredestimate
Acknowledgment
Theauthor gratefully acknowledges theDeanship of ScientificResearch at the University of Taibah The author is deeplyindebted to the referee for providing constructive commentsand help in improving the contents of this paper
References
[1] Z Ben Nahia and N Ben Salem ldquoSpherical harmonics andapplications associated with the Weinstein operatorrdquo in Pro-ceedings of the International Conference on PotentialTheory heldin Kouty Czech Republic (ICPT rsquo94) pp 235ndash241 1996
[2] Z Ben Nahia and N Ben Salem ldquoOn a mean value propertyassociated with the Weinstein operatorrdquo in Proceedings of theInternational Conference on Potential Theory held in KoutyCzech Republic (ICPT rsquo94) pp 243ndash253 1996
[3] M Brelot ldquoEquation de Weinstein et potentiels de MarcelRieszrdquo in Seminaire de Theorie de Potentiel Paris No 3 vol 681of Lecture Notes in Mathematics pp 18ndash38 Springer BerlinGermany 1978
[4] H Mejjaoli and M Salhi ldquoUncertainty principles for theweinstein transformrdquo Czechoslovak Mathematical Journal vol61 no 4 pp 941ndash974 2011
[5] H Mejjaoli and A Ould Ahmed Salem ldquoWeinstein Gabortransform and applicationsrdquo Advanced Studies in Pure Mathe-matics vol 2 no 3 pp 203ndash210 2012
[6] H Mejjaoli ldquoBesov spaces associated withthe Weinstein opera-tor and applicationsrdquo In press
[7] T Kawazoe and H Mejjaoli ldquoGeneralized Besov spaces andtheir applicationsrdquo Tokyo Journal of Mathematics vol 35 no 2pp 297ndash320 2012
[8] H Mejjaoli ldquoLittlewood-Paley decomposition associated withthe Dunkl operators and paraproduct operatorsrdquo Journal ofInequalities in Pure and Applied Mathematics vol 9 no 4 pp1ndash25 2008
[9] H Mejjaoli and N Sraeib ldquoGeneralized sobolev spaces inquantum calculus and applicationsrdquo Journal of Inequalities andSpecial Functions vol 1 no 4 pp 43ndash64 2012
[10] H Mejjaoli ldquoGeneralized homogeneous Besov spaces and theirapplicationsrdquo Serdica Mathematical Journal vol 38 no 4 pp575ndash614 2012
[11] H Triebel Interpolation Theory Functions Spaces DifferentialOperators North-Holland AmsterdamThe Netherlands 1978
[12] V S Guliev ldquoOn maximal function and fractional integralassociated with the Bessel differential operatorrdquo MathematicalInequalities and Applications vol 6 no 2 pp 317ndash330 2003
Submit your manuscripts athttpwwwhindawicom
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
MathematicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
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Hindawi Publishing Corporationhttpwwwhindawicom
Differential EquationsInternational Journal of
Volume 2014
Applied MathematicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Probability and StatisticsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Mathematical PhysicsAdvances in
Complex AnalysisJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
OptimizationJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
CombinatoricsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
International Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Operations ResearchAdvances in
Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Function Spaces
Abstract and Applied AnalysisHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
International Journal of Mathematics and Mathematical Sciences
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Algebra
Discrete Dynamics in Nature and Society
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Decision SciencesAdvances in
Discrete MathematicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom
Volume 2014 Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Stochastic AnalysisInternational Journal of
6 Journal of Function Spaces and Applications
By definition of the homogeneous Weinstein-Besov spaceswe therefore infer10038171003817100381710038171198911003817100381710038171003817B1199041120573
11990111199021(R119889+1+
)
= (
infin
sum
119895=minusinfin
(2119895119904110038171003817100381710038171003817Δ 119895119891
100381710038171003817100381710038171198711199011
120573(R119889+1+
))
1199021
)
11199021
le 119862(sum
119895isinZ
(211989511990412119895(119889+2120573+2)(1119901minus1119901
1)10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
1199021
)
11199021
le 119862(sum
119895isinZ
(211989511990410038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
1199021
)
11199021
le 11986210038171003817100381710038171198911003817100381710038171003817B119904120573
119901119902(R119889+1+
)
(57)
since 119902 le 1199021 This gives the inclusion
Proposition 21 (1) If 119906 belongs to B119904120573
119901119902(R119889+1
+) cap
B119905120573
119901119902(R119889+1
+)
then 119906 belongs to B120579119904+(1minus120579)119905120573
119901119902 (R119889+1
+) for all 120579 isin [0 1] and
119906B120579119904+(1minus120579)119905120573
119901119902(R119889+1+
)le 119906
120579
B119904120573
119901119902(R119889+1+
)119906
1minus120579
B119905120573
119901119902(R119889+1+
) (58)
(2) If 119906 belongs to B119904120573
119901infin(R119889+1
+) cap
B119905120573
119901infin(R119889+1
+) and 119904 lt 119905
then 119906 belongs to B120579119904+(1minus120579)119905120573
1199011(R119889+1
+) for all 120579 isin (0 1) and there
exists a positive constant 119862(119905 119904) such that
119906B120579119904+(1minus120579)119905120573
1199011(R119889+1+
)le 119862 (119905 119904) 119906
120579
B119904120573
119901infin(R119889+1+
)119906
1minus120579
B119905120573
119901infin(R119889+1+
) (59)
(3) If 119906 belongs to B119904120573
119901infin(R119889+1
+) cap
B119904+120576120573
119901infin (R119889+1
+) and 120576 gt
0 then 119906 belongs to B119904120573
1199011(R119889+1
+) and there exists a positive
constant 119862 such that
119906B119904120573
1199011(R119889+1+
)le
119862
120576
119906B119904120573
119901infin(R119889+1+
)log
2(119890 +
119906B119904+120576120573
119901infin(R119889+1+
)
119906B119904120573
119901infin(R119889+1+
)
)
(60)
Proof (1) is obvious from the Holderrsquos inequality As for (2)we write 119906
B120579119904+(1minus120579)119905120573
1199011(R119889+1+
)as
sum
119895le119873
2119895(120579119904+(1minus120579)119905)10038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)+ sum
119895gt119873
2119895(120579119904+(1minus120579)119905)10038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
(61)
where 119873 is chosen here after By the definition of thehomogeneous Weinstein-Besov norms we see that
2119895(120579119904+(1minus120579)119905)10038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 2
119895(1minus120579)(119905minus119904)119906
B119904120573
119901infin(R119889+1+
)
2119895(120579119904+(1minus120579)119905)10038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 2
minus119895120579(119905minus119904)119906
B119905120573
119901infin(R119889+1+
)
(62)
and thus 119906B120579119904+(1minus120579)119905120573
1199011(R119889+1+
)is dominated by
119906B119904120573
119901infin(R119889+1+
)sum
119895le119873
2119895(1minus120579)(119905minus119904)
+ 119906B119905120573
119901infin(R119889+1+
)sum
119895gt119873
2minus119895120579(119905minus119904)
le 119862119906B119904120573
119901infin(R119889+1+
)
2(119873+1)(1minus120579)(119905minus119904)
2(1minus120579)(119905minus119904)
minus 1
+ 119906B119905120573
119901infin(R119889+1+
)
2minus119873120579(119905minus119904)
1 minus 2minus120579(119905minus119904)
(63)
Hence in order to complete the proof of (2) it suffices tochoose119873 such that
119906B119905120573
119901infin(R119889)
119906B119904120573
119901infin(R119889)
le 2119873(119905minus119904)
lt 2
119906B119905120573
119901infin(R119889)
119906B119904120573
119901infin(R119889)
(64)
As for (3) it is easy to see that 119906B119904120573
1199011(R119889+1+
)is dominated as
sum
119895le119873minus1
211989511990410038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)+ sum
119895ge119873
211989511990410038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
le (119873 + 1) 119906B119904120573
119901infin(R119889+1+
)+
2minus(119873minus1)120576
2120576minus 1
119906B119904+120576120573
119901infin(R119889+1+
)
(65)
Hence letting
119873 = 1 + [
[
1
120576
log2
119906B119904+120576120573
119901infin(R119889+1+
)
119906B119904120573
119901infin(R119889+1+
)
]
]
(66)
we can obtain the desired estimate
Proposition 22 Let 119902 isin (1infin) and let 119904 isin R such that0 lt 119904 lt (119889 + 2120573 + 2)119902 then one has
B119904120573
119902119902(R
119889+1
+) =
F119904120573
119902119902(R
119889+1
+) 997893rarr
F119904120573
119902infin(R
119889+1
+)
997893rarrF119904minus((119889+2120573+2)119902)120573
infininfin(R
119889+1
+)
(67)
H119904
119902120573(R
119889+1
+) =
F119904120573
1199022(R
119889+1
+) 997893rarr
F119904120573
119902infin(R
119889+1
+)
997893rarrF119904minus((119889+2120573+2)119902)120573
infininfin(R
119889+1
+)
(68)
Proof We obtain these results by the similar ideas used in thenonhomogeneous case (cf [6])
Theorem 23 Let 119886 119887 gt 0 and let 1199021 1199022 isin [1infin] Let120579 = 119886(119886 + 119887) isin (0 1) and let 1119901 = (1 minus 120579)1199021 +
1205791199022 Then there exists a constant 119862 such that for every119891 isin
F119886120573
1199021infin(R119889+1
+) cap
Fminus119887120573
1199022infin(R119889+1
+) then one has
1003816100381610038161003816119891 (119909)
1003816100381610038161003816le 119862(sup
119895isinZ
2119886119895 10038161003816100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
1minus120579
(sup119895isinZ
2minus119887119895 10038161003816
100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
120579
(69)
In particular one gets
10038171003817100381710038171198911003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
10038171003817100381710038171198911003817100381710038171003817
1minus120579
F119886120573
1199021infin(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
120579
Fminus119887120573
1199022infin(R119889+1+
) (70)
Journal of Function Spaces and Applications 7
Proof Let 119891 be a Schwartz class we have
1003816100381610038161003816119891 (119909)
1003816100381610038161003816le sum
119895isinZ
10038161003816100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816
le sum
119895isinZ
min(2minus119886119895sup119895isinZ
(2119886119895 10038161003816100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
2119895119887sup119895isinZ
(2minus119895119887 10038161003816
100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816))
(71)
We define119873(119909) as the largest index such that
2119895119887sup119895isinZ
(2minus119895119887 10038161003816
100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816) le 2
minus119886119895sup119895isinZ
(2119886119895 10038161003816100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816) (72)
and we write1003816100381610038161003816119891 (119909)
1003816100381610038161003816le sum
119895le119873(119909)
2119895119887sup119895isinZ
(2minus119895119887 10038161003816
100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
+ sum
119895gt119873(119909)
2minus119886119895sup
119895
(2119886119895 10038161003816100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
le 119862(sup119895isinZ
2119886119895 10038161003816100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
119887(119886+119887)
times (sup119895isinZ
2minus119887119895 10038161003816
100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
119886(119886+119887)
(73)
Thus (69) is proved In order to obtain (70) it is enough toapply the Holder inequality in the expression above since wehave 120579 = 119886(119886+119887) isin (0 1) and let 1119901 = (1minus120579)1199021+1205791199022
Corollary 24 Let 119902 isin (1infin) and let 119904 isin R such that 0 lt 119904 lt
(119889 + 2120573 + 2)119902 then one has
10038171003817100381710038171198911003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
10038171003817100381710038171198911003817100381710038171003817
1minus(119902119901)
Bminus((2120573+2+119889)119902minus119904)120573
infininfin (R119889+1
+ )
10038171003817100381710038171198911003817100381710038171003817
119902119901
B119904120573
119902119902(R119889+1
+ )
(74)
10038171003817100381710038171198911003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
10038171003817100381710038171198911003817100381710038171003817
1minus(119902119901)
Bminus((2120573+2+119889)119902minus119904)120573
infininfin (R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
119902119901
H119904119902120573(R119889+1+
) (75)
where 119901 = 119902(2120573 + 2 + 119889)(2120573 + 2 + 119889 minus 119902119904)
Proof By choosing 119886 = 119904 gt 0 minus119887 = 119904 minus (119889 + 2120573 + 2)119902 lt 01199021 = 119902 and 1199022 = infin we deduce (74) from the relations (70)and (67) In the same way we deduce (75) from the relations(70) and (68)
4 Generalized Heat Equation
41 Characterization for the Weinstein-Besov Spaces TheWeinstein heat equation reads
120597119905119906 (119905 119909) minus Δ 120573119906 (119905 119909) = 119891 (119905 119909) (119905 119909) isin [0infin) timesR119889+1
+
119906|119905=0 = 119892
(76)
We introduce the Weinstein heat semigroup 119867120573(119905) for theWeinstein-Laplace operator
119867120573 (119905) 119892 (119909) =
int
R119889+1+
Γ120573 (119905 119909 119910) 119892 (119910) 119889120583120573 (119910) if 119905 gt 0
119892 (119909) if 119905 = 0(77)
where Γ120573 is the Weinstein heat kernel defined by
Γ120573 (119905 119909 119910) = 120591119909 (119864(120573)
119905) (119910) (78)
where
119864(120573)
119905(119910) =
2
1205871198892Γ (120573 + 1) (4119905)
120573+1+1198892119890minus11991024119905 (79)
Thus
119867120573 (119905) 119892 (119909) = 119892lowast119882119864(120573)
119905 (119909) (80)
In practice we use the integral formulation of (76)
119906 (119905 119909) = 119867120573 (119905) 119892 (119909) + 119866120573 (119891) (119905 119909)
= 119867120573 (119905) 119892 (119909) + int
119905
0
119867120573 (119905 minus 119904) 119891 (119904 119909) 119889119904
(81)
Remark 25 The function 119864(120573)119905
is the Gauss kernel associatedwith Weinstein operators This function satisfies
forall120585 isin R119889+1
+ F119882 (119864
(120573)
119905) (120585) = 119890
minus1199051205852
(82)
Proposition 26 Let 1 le 119901 le 119903 le infin and let 119891 isin 119871119901
120573(R119889+1
+)
Then the operator 119867120573(119905) maps 119871119901
120573(R119889+1
+) continuously to
119871119903
120573(R119889+1
+) and
10038171003817100381710038171003817119867120573 (119905) 119891
10038171003817100381710038171003817119871119903120573(R119889)
le 119862119905minus((119889+2120573+2)2)(1119901minus1119903)1003817
1003817100381710038171198911003817100381710038171003817119871119901
120573(R119889)
(83)
Moreover1003817100381710038171003817100381710038171003817
(minusΔ 120573)
1205752
119867120573 (119905) 119891
1003817100381710038171003817100381710038171003817119871119903120573(R119889)
le 119862119905minus1205752minus((119889+2120573+2)2)(1119901minus1119903)1003817
1003817100381710038171198911003817100381710038171003817119871119901
120573(R119889)
(84)
for all 120575 gt 0
Proof It follows from the relations (80) and (29) combinedwith scaling property of the kernel 119864(120573)
119905
In this section we prove estimates for the Weinstein heatsemigroupThese estimates are based on the following result
Lemma 27 Let C be an annulus Positive constants 119888 and 119862exist such that for any 119901 in [1infin] and any couple (119905 120582) ofpositive real numbers one has
suppF119882 (119906) sub 120582C 997904rArr
10038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
le 119862119890minus1198881199051205822
119906119871119901
120573(R119889+1+
)
(85)
8 Journal of Function Spaces and Applications
Proof We again consider a function Θ in 119863(R119889+1
+ 0) the
value of which is identically 1 in neighborhood of annulusCWe can also assume without loss of generality that 120582 = 1 Wethen have
119867120573 (119905) 119906 = 119892 (119905 sdot) lowast119882119906 (86)where
119892 (119905 sdot) = Fminus1
119882(Θ (120585) 119890
minus1199051205852
) (87)
The lemma is proved provided that we can find positive realnumbers 119888 and 119862 such that
forall119905 gt 01003817100381710038171003817119892 (119905 sdot)
10038171003817100381710038171198711120573(R119889+1+
)le 119862119890
minus119888119905 (88)
To begin we perform integrations by parts in (87) We get1003816100381610038161003816119892 (119905 119909)
1003816100381610038161003816=
1
119888120573
(1 + 1199092)
minus(119889+[2120573]+3)
times int
R119889+1+
Λ (119909 120585) (119868119889 minus Δ 120573)
119889+[2120573]+3
times (Θ (120585) 119890minus1199051205852
) 119889120583120573 (120585)
(89)
Using Leibnizrsquos formula we obtain1003816100381610038161003816119892 (119905 119909)
1003816100381610038161003816le 119862(1 + 119909
2)
minus(119889+[2120573]+3)
119890minus119888119905 (90)
and (88) follows
For any interval 119868 of R (bounded or unbounded) wedefine themixed space-time 119871119901(119868 119871119902
120573(R119889+1
+)) Banach space of
(classes of) measurable functions 119906 119868 rarr 119871119902
120573(R119889+1
+) such
that 119906119871119901(119868119871
119902
120573(R119889+1+
))lt infin with
119906119871119901(119868119871119902
120573(R119889+1+
))= (int
119868
119906 (119905 sdot)119901
119871119902
120573(R119889+1+
)119889119905)
1119901
if 1 le 119901 119902 lt infin
119906119871infin(119868119871119902
120573(R119889+1+
))= ess sup
119905isin119868
119906 (119905 sdot)119871119902
120573(R119889+1+
) if 1 le 119902 lt infin
(91)Corollary 28 Let C be an annulus and 120582 a positive realnumber Let 1199060 (resp 119891 = 119891(119905 119909)) satisfy suppF119882(1199060) sub 120582C(resp suppF119882(119891(119905 sdot)) sub 120582C for all 119905 in [0 119879]) Consider 119906 asolution of
120597119905119906 minus Δ 120573119906 = 0 119906|119905=0 = 1199060 (92)and V a solution of
120597119905V minus Δ 120573V = 119891 (119905 sdot) V|119905=0 = 0 (93)There exist positive constants 119888 and 119862 depending only on Csuch that for any 1 le 119886 le 119887 le infin and 1 le 119901 le 119902 le infin we have
119906119871119902([0119879]119871119887120573(R119889+1+
))le 119862120582
(119889+2120573+2)(1119886minus1119887)120582minus21199021003817
1003817100381710038171199060
1003817100381710038171003817119871119886120573(R119889+1+
)
V119871119902([0119879]119871119887120573(R119889+1+
))le 119862120582
minus2(1+1119902minus1119901)120582(119889+2120573+2)(1119886minus1119887)
times10038171003817100381710038171198911003817100381710038171003817119871119901([0119879]119871119886
120573(R119889+1+
))
(94)
Proof It suffices to use the fact that
119906 (119905 sdot) = 119867120573 (119905) 1199060 V (119905 sdot) = int119905
0
119867120573 (119905 minus 119904) 119891 (119904 sdot) 119889119904
(95)
Combining Lemma 27 and Youngrsquos inequality (29) withscaling property of the kernel 119864(120573)
119905now yields the result
Theorem 29 Let 119904 be a positive real number and (119901 119903) isin
[1infin]2 A constant 119862 exists which satisfies the following
property For 119906 isin Bminus2119904120573
119901119903 (R119889+1
+) one has
119862minus1119906
Bminus2119904120573
119901119903(R119889+1+
)le
10038171003817100381710038171003817100381710038171003817
10038171003817100381710038171003817119905119904119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
10038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
le 119862119906Bminus2119904120573
119901119903(R119889+1+
)
(96)
To prove this result we need the following lemma
Lemma 30 There exist two positive constants 120581 and 119862
depending only on 120593 such that for all 1 le 119901 le infin 120591 ge 0 and119895 isin Z one has
10038171003817100381710038171003817Δ 119895 (119867120573 (120591) 119906)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862119890
minus1205812211989512059110038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
) (97)
Proof The result follows immediately by applying Lemma 27and because Δ 119895(119867120573(120591))119906 = (119867120573(120591)Δ 119895)119906
Proof of Theorem 29 Using Lemma 30 and considering thefact that the operator Δ 119895 commutes with the operator 119867120573(119905)
and the definition of the homogeneous Weinstein-Besov(semi) norm we get
10038171003817100381710038171003817119905119904119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862119906
Bminus2119904120573
119901119903(R119889+1+
)sum
119895isinZ
11990511990422119895119904119890minus12058111990522119895
119888119903119895
(98)
where (119888119903119895)119895isinZ denotes as in all this proof a generic elementof the unit sphere of 119897119903(Z) In the case when 119903 = infin therequired inequality comes immediately from the followingeasy result For any positive 119904 we have
sup119905gt0
sum
119895isinZ
11990511990422119895119904119890minus12058111990522119895
lt infin (99)
In the case 119903 lt infin using the Holder inequality with theweight 22119895119904119890minus1205811199052
2119895
(99) and the Fubini theorem we obtain
int
infin
0
11990511990311990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)
119889119905
119905
le 119862119906119903
Bminus2119904120573
119901119903(R119889+1+
)int
infin
0
(sum
119895isinZ
11990511990422119895119904119890minus12058111990522119895
)
119903minus1
times (sum
119895isinZ
11990511990422119895119904119890minus12058111990522119895
119888119903
119903119895)
119889119905
119905
Journal of Function Spaces and Applications 9
le 119862119906119903
Bminus2119904120573
119901119903(R119889+1+
)int
infin
0
(sum
119895isinZ
11990511990422119895119904119890minus12058111990522119895
119888119903
119903119895)
119889119905
119905
le 119862119906119903
Bminus2119904120573
119901119903(R119889+1+
)sum
119895isinZ
119888119903
119903119895int
infin
0
(11990511990422119895119904119890minus12058111990522119895
)
119889119905
119905
le 119862Γ (119904) 119906119903
Bminus2119904120573
119901119903(R119889+1+
)
(100)
In order to prove the other inequality let us observe thatfor any 119904 greater than minus1 we have
Δ 119895119906 =
1
Γ (119904 + 1)
int
infin
0
119905119904(minusΔ 120573)
119904+1
119867120573 (119905) Δ 119895119906 119889119905 (101)
Then Lemma 30 Proposition 9 and the fact that the operatorΔ 119895 commutes with the operator119867120573(119905) lead to the following
10038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862int
infin
0
11990511990422119895(119904+1)
119890minus1205811199052211989510038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889119905
(102)
In the case 119903 = infin we simply write
10038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862(sup
119905gt0
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
times int
infin
0
22119895(119904+1)
119890minus12058111990522119895
119889119905
le 11986222119895119904(sup119905gt0
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
(103)
In the case 119903 lt infin Holderrsquos inequality with the weight 119890minus12058111990522119895
gives
(int
infin
0
119905119904119890minus1205811199052211989510038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889119905)
119903
le 1198622minus2119895(119903minus1)
int
infin
0
119905119903119904119890minus1205811199052211989510038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)119889119905
(104)
Thanks to (99) and Fubinirsquos theorem we infer from (102) that
sum
119895isinZ
2minus211989511990311990410038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)le 119862int
infin
0
11990511990311990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)
119889119905
119905
(105)
The theorem is proved
Second Proof ofTheorem 29We only consider the case 1 le 119903 ltinfinThe case 119903 = infin can be shown similarlyWe first prove that
119862minus1119906
Bminus2119904120573
119901119903(R119889+1+
)le
10038171003817100381710038171003817100381710038171003817
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
10038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
(106)
It is easy to see that
Δ 119895119906 = 120594119895lowast119882119864(120573)
2minus2119895lowast119882119906
(107)
where 120594119895 = Fminus1
119882(120593(2
minus119895120585)119890
2minus21198951205852
) and119864(120573)2minus2119895
is the Gauss kernelassociated with Weinstein operators By relation (29) we get
10038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le
10038171003817100381710038171003817120594119895
100381710038171003817100381710038171198711120573(R119889+1+
)
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
) (108)
As10038171003817100381710038171003817120594119895
100381710038171003817100381710038171198711120573(R119889+1+
)= int
R119889+1+
100381610038161003816100381610038161003816F
minus1
119882(120593 (120585) 119890
1205852
)
100381610038161003816100381610038161003816119889120583120573 (120585) lt infin (109)
we obtain10038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
) (110)
Moreover simple calculations give that
119864(120573)
2minus2119895lowast119882119906 = 119867120573 (2
minus4119895minus 119905
2) (119864
(120573)
1199052lowast119882119906)
(111)
Thus from Proposition 26 it follows that100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
100381710038171003817100381710038171003817119864(120573)
1199052lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1
+ )
(112)
for any 119905 isin [2minus119895minus1 2minus119895] which implies that
sum
119895isinZ
2minus211990411989511990310038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)
le 119862 sum
119895isinZ
int
2minus119895
2minus119895minus1(119905
2119904100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903119889119905
119905
le 119862int
infin
0
(1199052119904100381710038171003817100381710038171003817119864(120573)
1199052lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903119889119905
119905
le 119862int
infin
0
(11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903119889119905
119905
(113)
where we have used the fact that 119864(120573)1199052lowast119882119906 = 119867120573(119905
2)119906
We now prove that10038171003817100381710038171003817100381710038171003817
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
10038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
le 119862119906Bminus2119904120573
119901119903(R119889+1+
) (114)
Indeed one has
119864(120573)
2minus2119895lowast119882119906 = sum
119899isinZ
119864(120573)
2minus2119895lowast119882Δ 119899+119895119906 (115)
Arguing as above we have100381710038171003817100381710038171003817119864(120573)
1199052lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1
+ )
(116)
for any 119905 isin [2minus119895 21minus119895] Thus10038171003817100381710038171003817100381710038171003817
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
10038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
= 2
100381710038171003817100381710038171003817100381710038171003817
1003817100381710038171003817100381710038171199052119904119864(120573)
1199052lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)
100381710038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
le 119862 sum
119895isinZ
int
21minus119895
2minus119895(2
minus2119895119904100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903119889119905
119905
le 119862 sum
119895isinZ
(2minus2119895119904
sum
119899isinZ
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
(117)
10 Journal of Function Spaces and Applications
On the other hand it is easy to see that100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)le 1198622
minus211989911990410038171003817100381710038171003817Δ 119899+119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
) (118)
for any 119904 gt 0 For 0 lt 1199041 lt 119904 lt 1199042 and by using theMinkowskiinequality we have
sum
119895isinZ
(2minus2119895119904
sum
119899isinZ
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
le sum
119895isinZ
(2minus2119895119904
0
sum
minusinfin
2minus21198991199041
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
+ sum
119895isinZ
(2minus2119895119904
sum
119899isinN
2minus21198991199042
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
le 119862(
0
sum
minusinfin
2minus2119899(119904
1minus119904)(sum
119895isinZ
(2minus2(119899+119895)11990311990410038171003817
100381710038171003817Δ 119899+119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
)
1119903
)
119903
+ 119862(sum
N
2minus2119899(119904
2minus119904)(sum
119895isinZ
(2minus2(119899+119895)11990311990410038171003817
100381710038171003817Δ 119899+119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
)
1119903
)
119903
le 119862 sum
119895isinZ
2minus211989511990311990410038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)
(119)
The result is immediately from (117) and (119)
42 Embedding Sobolev Theorems
Theorem 31 Let 1 lt 119901 lt infin and let 0 lt 119904 lt (119889 + 2120573 +
2)119901There exists a positive constant119862 such that for all function119891 isin
H119904
119901120573(R119889+1
+) one has
10038171003817100381710038171198911003817100381710038171003817119871119902
120573(R119889+1+
)le 119862
10038171003817100381710038171198911003817100381710038171003817
1minus120579
H119904119901120573(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
120579
B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
) (120)
where 120579 = 119904119901(119889+2120573+2) and 119902 = 119901(119889+2120573+2)(119889+2120573+2minus119901119904)
Proof Bydensity we can suppose that119891belongs toSlowast(R119889+1
)It is easy to see that
119891 = int
infin
0
119867120573 (119905) Δ 120573119891119889119905(121)
and decompose the integral in two parts as follows
119891 = int
119860
0
119867120573 (119905) Δ 120573119891119889119905 + int
infin
119860
119867120573 (119905) Δ 120573119891119889119905(122)
where 119860 is a constant to be fixed laterOn the other hand byTheorem 29 we obtain10038171003817100381710038171003817119867120573 (119905) Δ 120573119891
10038171003817100381710038171003817119871infin120573(R119889+1+
)
le
119862
1199051minus(12)(119904minus(119889+2120573+2)119901)
10038171003817100381710038171198911003817100381710038171003817B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
)
(123)
Therefore after integrating we get
int
infin
119860
10038171003817100381710038171003817119867120573 (119905) Δ 120573119891
10038171003817100381710038171003817119871infin120573(R119889+1+
)119889119905
le 119860(12)(119904minus(119889+2120573+2)119901)1003817
1003817100381710038171198911003817100381710038171003817B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
)
(124)
On the other hand denoting 119892 = (minusΔ 120573)1199042119891 we have
119867120573 (119905) Δ 120573119891 =
1
(minus119905)1minus1199042
119867120573 (119905) (minus119905Δ 120573)
1minus1199042
119892 (125)
We proceed as in [8] we prove that1003816100381610038161003816100381610038161003816
119867120573 (119905) (minus119905Δ 120573)
1minus1199042
119892 (119909)
1003816100381610038161003816100381610038161003816
le 119862 (119904)119872120573 (119892) (119909) (126)
where119872120573(119892) is a maximal function of 119892 associated with theWeinstein operators (cf [12])
This leads to100381610038161003816100381610038161003816100381610038161003816
int
119860
0
119867120573 (119905) Δ 120573119891 (119909) 119889119905
100381610038161003816100381610038161003816100381610038161003816
le 1198621198601199042119872120573 (119892) (119909) (127)
In conclusion we get10038161003816100381610038161003816100381610038161003816
int
infin
0
119867120573 (119905) Δ 120573119891 (119909) 119889119905
10038161003816100381610038161003816100381610038161003816
le 119862 (1198601199042119872120573 (119892) (119909)
+119860(12)(119904minus(119889+2120573+2)119901)1003817
1003817100381710038171198911003817100381710038171003817B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
))
(128)
and the choice of 119860 such that
119860(119889+2120573+2)2119901
119872120573 (119892) (119909) =10038171003817100381710038171198911003817100381710038171003817B119904minus(119889+2120573+2)119901120573
infininfin (R119889+1+
)(129)
ensures that10038161003816100381610038161003816100381610038161003816
int
infin
0
119867120573 (119905) Δ 120573119891 (119909) 119889119905
10038161003816100381610038161003816100381610038161003816
le 119862(119872120573(119892)(119909))
1minus(119901119904(119889+2120573+2))10038171003817100381710038171198911003817100381710038171003817
119901119904(119889+2120573+2)
B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
)
(130)
Finally taking the 119871119902120573norm with 119902 = 119901(119889 + 2120573 + 2)(119889 + 2120573 +
2minus119901119904) ends the proof thanks to the fact themaximal function119872120573 is bounded of 119871119902
120573(R119889+1
+) into itself for 119902 gt 1
Theorem 32 Let 1 lt 119901 lt 119902 lt infin For all function 119891 such that119891 isin
H1199041
119901120573(R119889+1
+)⋂
Bminus120573120573
infininfin(R119889+1
+) one has
10038171003817100381710038171198911003817100381710038171003817H119904119901120573(R119889+1+
)le 119862
10038171003817100381710038171198911003817100381710038171003817
120579
H1199041
119901120573(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
1minus120579
Bminus120573120573
infininfin(R119889+1
+) (131)
where 120579 = 119901119902 119904 = 1205791199041 minus (1 minus 120579)120573 with 120573 gt 0 minus120573 lt 119904 lt 1199041
Proof It suffices to prove that1003817100381710038171003817100381710038171003817
(minusΔ 120573)
(119904minus1199041)2
119891
1003817100381710038171003817100381710038171003817119871119902
120573(R119889+1+
)
le 11986210038171003817100381710038171198911003817100381710038171003817
120579
119871119901
120573(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
1minus120579
Bminus120573minus1199041120573
infininfin (R119889+1+
)
(132)
Journal of Function Spaces and Applications 11
Indeed we use the following identity (which may be easilyproven by taking the Weinstein transform in 119909 of both sides)
(minusΔ 120573)
minus1205752
119891 (119909) =
1
Γ (1205752)
int
infin
0
1199051205752minus1
119867120573 (119905) 119891 (119909) 119889119905 (133)
with 120575 = 1199041 minus 119904 gt 0We decompose the integral in two parts as follows
(minusΔ 120573)
minus1205752
119891 (119909) =
1
Γ (1205752)
int
119879
0
1199051205752minus1
119867120573 (119905) 119891 (119909) 119889119905
+
1
Γ (1205752)
int
infin
119879
1199051205752minus1
119867120573 (119905) 119891 (119909) 119889119905
(134)
where 119879 is a constant to be fixed laterWe proceed as in [8] we obtain
10038161003816100381610038161003816119867120573 (119905) 119891 (119909)
10038161003816100381610038161003816le 119862119872120573 (119891) (119909) (135)
On the other hand we use Theorem 29 and the fact that 119891belongs to Bminus120573minus119904
1120573
infininfin(R119889+1
+) to deduce that
10038161003816100381610038161003816119867120573 (119905) 119891 (119909)
10038161003816100381610038161003816le 119862119905
(minus120573minus1199041)210038171003817100381710038171198911003817100381710038171003817Bminus120573minus1199041120573
infininfin (R119889+1+
) (136)
Thus by applying the preceding estimates on the right part of(134) we obtain
1003816100381610038161003816100381610038161003816
(minusΔ 120573)
minus1205752
119891 (119909)
1003816100381610038161003816100381610038161003816
le
1198621
Γ (1205752)
1198791205752119872120573 (119891) (119909)
+
1198622
Γ (1205752)
119879(120575minus120573minus119904
1)210038171003817100381710038171198911003817100381710038171003817Bminus120573minus1199041120573
infininfin (R119889+1+
)
(137)
We fix now
119879 = (
10038171003817100381710038171198911003817100381710038171003817Bminus120573minus1199041120573
infininfin (R119889+1+
)
119872120573 (119891) (119909)
)
2(120573+1199041)
(138)
We obtain
1003816100381610038161003816100381610038161003816
(minusΔ120573)
minus1205752
119891 (119909)
1003816100381610038161003816100381610038161003816
le
1198621 + 1198622
Γ (1205752)
(119872120573(119891)(119909))
12057910038171003817100381710038171198911003817100381710038171003817
1minus120579
Bminus120573minus1199041120573
infininfin (R119889+1+
)
(139)
Thus we deduce that1003817100381710038171003817100381710038171003817
(minusΔ120573)
minus1205752
119891
1003817100381710038171003817100381710038171003817119871119902
120573(R119889+1+
)
le
1198621 + 1198622
Γ (1205752)
10038171003817100381710038171003817119872120573 (119891)
10038171003817100381710038171003817
120579
119871119901
120573(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
1minus120579
Bminus120573minus1199041120573
infininfin (R119889+1+
)
(140)
To conclude we used the fact that the maximal function119872120573
is bounded of 119871119902120573(R119889+1
+) into itself for 119902 gt 1
43 Estimates in Generalized Besov Spaces For any interval 119868ofR (bounded or unbounded) and a normed space 119865(R119889+1
+)
we define the mixed space-time 119871119901(119868 119865(R119889+1
+)) space of
(classes of) measurable functions 119906 119868 rarr 119865(R119889+1
+) such that
||119906||119871119901(119868119865(R119889+1+
)) lt infin with
119906119871119901(119868119865(R119889+1+
)) = (int
119868
119906 (119905 sdot)119901
119865(R119889+1+
)119889119905)
1119901
if 1 le 119901 lt infin
119906119871infin(119868119865(R119889+1+
)) = ess sup119905isin119868
119906 (119905 sdot)119865(R119889+1+
)
(141)
For any interval 119868 of R (bounded or unbounded) anda Banach space 119883 we define the mixed space-time 119862(119868119883)space of continuous functions 119868 rarr 119883 When 119868 is bounded119862(119868119883) is a Banach space with the norm of 119871infin(119868 119883)
Theorem 33 Let 119904 isin R and 1 le 119901 119902 119903 le infin Let 119879 gt 0 119892 isin
B119904120573
119901119903(R119889+1
+) and119891 in 119871119902((0 119879) B
119904minus2+(2119902)120573
119901119903 (R119889+1
+)) Then (76)
has a unique solution
119906 isin 119871119902((0 119879)
B119904+(2119902)120573
119901119903(R
119889+1
+))
⋂119871infin((0 119879)
B119904120573
119901119903(R
119889+1
+))
(142)
and there exists a constant 119862 such that for all 1199021 isin [119902infin] onehas
1199061198711199021 ((0119879)B
119904+(21199021)120573
119901119903(R119889+1+
))
le 119862(10038171003817100381710038171198921003817100381710038171003817B119904120573
119901119903(R119889+1+
)+10038171003817100381710038171198911003817100381710038171003817119871119902((0119879)B
119904minus2+(2119902)120573
119901119903(R119889+1+
)))
(143)
If in addition 119903 lt infin then 119906 isin 119862([0 119879] B119904120573
119901119903(R119889+1
+))
Proof Since 119892 and 119891 are temperate distributions (76) has aunique solution 119906 in S1015840
((0 119879) timesR119889+1
+) which satisfies
F119882 (119906) (119905 120585) = 119890minus1199051205852
F119882 (119892) (120585)
+ int
119905
0
119890(120591minus119905)120585
2
F119882 (119891) (120591 120585) 119889120591
(144)
Next we notice that applying Δ 119895 to (76) and using formula(81) yield
Δ 119895119906 (119905 sdot) = 119867120573 (119905) Δ 119895119892 + int
119905
0
119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot) 119889120591(145)
Therefore
10038171003817100381710038171003817Δ 119895119906 (119905 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le
10038171003817100381710038171003817119867120573(119905)Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+ int
119905
0
10038171003817100381710038171003817119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591
(146)
12 Journal of Function Spaces and Applications
By virtue of Lemma 30 we thus have for some 120581 gt 0
10038171003817100381710038171003817Δ 119895119906(119905 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
le 119862[119890minus1205812211989511990510038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+ int
119905
0
119890minus12058122119895(119905minus120591) 10038171003817
100381710038171003817Δ 119895119891 (120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591]
(147)
Applying convolution inequalities we get
10038171003817100381710038171003817Δ 119895119906
100381710038171003817100381710038171198711199021 ((0119879)119871
119901
120573(R119889+1+
))
le 119862[
[
((
1 minus 119890minus120581119879119902122119895
120581119902122119895
)
11199021
)
10038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+((
1 minus 119890minus120581119879119902222119895
120581119902222119895
)
11199022
)
10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119902((0119879)119871
119901
120573(R119889+1+
))
]
]
(148)
with 11199022 = 1+ 11199021 minus1119902 Finally taking the 119897119903(Z) norm we
conclude that (with the usual convention if 119903 = infin)
1199061198711199021 ((0119879)B
119904+(21199021)120573
119901119903(R119889+1+
))
le 119862[
[
sum
119895isinZ
((
1 minus 119890minus120581119879119902122119895
120581119902122119895
)
1199031199021
)(211989511990410038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
]
]
1119903
+ 119862[
[
sum
119895isinZ
((
1 minus 119890minus120581119879119902222119895
120581119902222119895
)
1199031199022
)
times (2119895(119904minus2+2119902)10038171003817
100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119902(0119879119871
119901
120573(R119889+1+
))
119903
]
]
1119903
(149)
which insures that 119906 isin 119871119902((0 119879)
B119904+(2119902)120573
119901119903 (R119889+1
+))
⋂119871infin((0 119879)
B119904120573
119901119903(R119889+1
+)) and yields the desired inequality
Since 119906 belongs to 119862([0 119879]B119904120573
119901119903(R119889+1
+)) in the case where
119903 is finite may be easily deduced from the density ofSlowast(R
119889+1)⋂
B119904120573
119901119903(R119889+1
+) in B
119904120573
119901119903(R)
Theorem 34 Let 119904 isin R 119879 gt 0 and 1 le 119901 119902 119903 le infinOne supposes that 119892 isin 119861
119904120573
119901119903(R119889+1
+) and 119891 isin 119871
119902((0 119879)
119861119904minus2+(2119902)120573
119901119903 (R119889+1
+)) Then (76) has a unique solution 119906 belong-
ing to
119871119902((0 119879) 119861
119904+(2119902)120573
119901119903(R
119889+1
+))⋂119871
infin((0 119879) 119861
119904120573
119901119903(R
119889+1
+))
(150)
and there exists a constant 119862 such that for all 119902 le 1199021 le infin
1199061198711199021 ((0119879)119861
119904+(21199021)120573
119901119903(R119889+1+
))
le 119862 [ (1 + 11987911199021)10038171003817100381710038171198921003817100381710038171003817119861119904120573
119901119903(R119889+1+
)
+ (1 + 1198791+1119902
1minus1119902
)10038171003817100381710038171198911003817100381710038171003817119871119902((0119879)119861
119904minus2+(2119902)120573
119901119903(R119889+1+
))]
(151)
If in addition 119903 lt infin then 119906 isin 119862([0 119879] 119861119904120573119901119903(R119889+1
+))
Proof Since 119892 119891 are tempered (76) has a unique solution 119906in S1015840
((0 119879) timesR119889+1
+) satisfying
F119882 (119906) (119905 120585) = 119890minus1199051205852
F119882 (119892) (120585)
+ int
119905
0
119890(120591minus119905)120585
2
F119882 (119891) (120591 120585) 119889120591
(152)
Hence applying Δ 119895 119895 ge 0 to (81) we see that
Δ 119895119906 (119905 sdot) = 119867120573 (119905) Δ 119895119892 + int
119905
0
119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot) 119889120591(153)
and thus by Lemma 30 we can deduce that10038171003817100381710038171003817Δ 119895119906 (119905 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
le
10038171003817100381710038171003817119867120573(119905)Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)+ int
119905
0
10038171003817100381710038171003817119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591
le 119862[119890minus1205812211989511990510038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+int
119905
0
119890minus12058122119895(119905minus120591)10038171003817
100381710038171003817Δ 119895119891(120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591]
(154)
Then it follows from convolution inequalities thatΔ 1198951199061198711199021 ((0119879)119871
119901
120573(R119889+1+
))is dominated by
(
1 minus 119890minus120581119879119902122119895
120581119902122119895
)
11199021
10038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119861119904120573
119901119903(R119889+1+
)
+ (
1 minus 119890minus120581119879119902222119895
120581119902222119895
)
11199022
10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119902((0119879)119871
119901
120573(R119889+1+
))
(155)
with 11199022 = 1 + 11199021 minus 1119902 Moreover similarly as above wecan obtain that
1003817100381710038171003817Δminus1119906(119905 sdot)
1003817100381710038171003817119871119901
120573(R119889+1+
)le1003817100381710038171003817Δminus1119892
1003817100381710038171003817119871119901
120573(R119889+1+
)
+ int
119905
0
1003817100381710038171003817Δminus1119891 (120591 sdot)
1003817100381710038171003817119871119901
120573(R119889+1+
)119889120591
(156)
and thus if 1 le 119902 le 1199021 le infin1003817100381710038171003817Δminus1119906
10038171003817100381710038171198711199021 ((0119879)119871
119901
120573(R119889+1+
))
le 119862(119879111990211003817100381710038171003817Δminus1119892
1003817100381710038171003817119871119901
120573(R119889+1+
)+ 119879
111990221003817100381710038171003817Δminus1119891
1003817100381710038171003817119871119902((0119879)119871
119901
120573(R119889+1+
)))
(157)
Journal of Function Spaces and Applications 13
Finally taking the 119897119903-normwith respect to 119895 in (155) and (157)with the usual convention if 119903 = infin we can deduce the desiredestimate
Acknowledgment
Theauthor gratefully acknowledges theDeanship of ScientificResearch at the University of Taibah The author is deeplyindebted to the referee for providing constructive commentsand help in improving the contents of this paper
References
[1] Z Ben Nahia and N Ben Salem ldquoSpherical harmonics andapplications associated with the Weinstein operatorrdquo in Pro-ceedings of the International Conference on PotentialTheory heldin Kouty Czech Republic (ICPT rsquo94) pp 235ndash241 1996
[2] Z Ben Nahia and N Ben Salem ldquoOn a mean value propertyassociated with the Weinstein operatorrdquo in Proceedings of theInternational Conference on Potential Theory held in KoutyCzech Republic (ICPT rsquo94) pp 243ndash253 1996
[3] M Brelot ldquoEquation de Weinstein et potentiels de MarcelRieszrdquo in Seminaire de Theorie de Potentiel Paris No 3 vol 681of Lecture Notes in Mathematics pp 18ndash38 Springer BerlinGermany 1978
[4] H Mejjaoli and M Salhi ldquoUncertainty principles for theweinstein transformrdquo Czechoslovak Mathematical Journal vol61 no 4 pp 941ndash974 2011
[5] H Mejjaoli and A Ould Ahmed Salem ldquoWeinstein Gabortransform and applicationsrdquo Advanced Studies in Pure Mathe-matics vol 2 no 3 pp 203ndash210 2012
[6] H Mejjaoli ldquoBesov spaces associated withthe Weinstein opera-tor and applicationsrdquo In press
[7] T Kawazoe and H Mejjaoli ldquoGeneralized Besov spaces andtheir applicationsrdquo Tokyo Journal of Mathematics vol 35 no 2pp 297ndash320 2012
[8] H Mejjaoli ldquoLittlewood-Paley decomposition associated withthe Dunkl operators and paraproduct operatorsrdquo Journal ofInequalities in Pure and Applied Mathematics vol 9 no 4 pp1ndash25 2008
[9] H Mejjaoli and N Sraeib ldquoGeneralized sobolev spaces inquantum calculus and applicationsrdquo Journal of Inequalities andSpecial Functions vol 1 no 4 pp 43ndash64 2012
[10] H Mejjaoli ldquoGeneralized homogeneous Besov spaces and theirapplicationsrdquo Serdica Mathematical Journal vol 38 no 4 pp575ndash614 2012
[11] H Triebel Interpolation Theory Functions Spaces DifferentialOperators North-Holland AmsterdamThe Netherlands 1978
[12] V S Guliev ldquoOn maximal function and fractional integralassociated with the Bessel differential operatorrdquo MathematicalInequalities and Applications vol 6 no 2 pp 317ndash330 2003
Submit your manuscripts athttpwwwhindawicom
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
MathematicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Mathematical Problems in Engineering
Hindawi Publishing Corporationhttpwwwhindawicom
Differential EquationsInternational Journal of
Volume 2014
Applied MathematicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Probability and StatisticsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Mathematical PhysicsAdvances in
Complex AnalysisJournal of
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OptimizationJournal of
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CombinatoricsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
International Journal of
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Operations ResearchAdvances in
Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Function Spaces
Abstract and Applied AnalysisHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
International Journal of Mathematics and Mathematical Sciences
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Algebra
Discrete Dynamics in Nature and Society
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Decision SciencesAdvances in
Discrete MathematicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom
Volume 2014 Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Stochastic AnalysisInternational Journal of
Journal of Function Spaces and Applications 7
Proof Let 119891 be a Schwartz class we have
1003816100381610038161003816119891 (119909)
1003816100381610038161003816le sum
119895isinZ
10038161003816100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816
le sum
119895isinZ
min(2minus119886119895sup119895isinZ
(2119886119895 10038161003816100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
2119895119887sup119895isinZ
(2minus119895119887 10038161003816
100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816))
(71)
We define119873(119909) as the largest index such that
2119895119887sup119895isinZ
(2minus119895119887 10038161003816
100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816) le 2
minus119886119895sup119895isinZ
(2119886119895 10038161003816100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816) (72)
and we write1003816100381610038161003816119891 (119909)
1003816100381610038161003816le sum
119895le119873(119909)
2119895119887sup119895isinZ
(2minus119895119887 10038161003816
100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
+ sum
119895gt119873(119909)
2minus119886119895sup
119895
(2119886119895 10038161003816100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
le 119862(sup119895isinZ
2119886119895 10038161003816100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
119887(119886+119887)
times (sup119895isinZ
2minus119887119895 10038161003816
100381610038161003816Δ 119895119891 (119909)
10038161003816100381610038161003816)
119886(119886+119887)
(73)
Thus (69) is proved In order to obtain (70) it is enough toapply the Holder inequality in the expression above since wehave 120579 = 119886(119886+119887) isin (0 1) and let 1119901 = (1minus120579)1199021+1205791199022
Corollary 24 Let 119902 isin (1infin) and let 119904 isin R such that 0 lt 119904 lt
(119889 + 2120573 + 2)119902 then one has
10038171003817100381710038171198911003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
10038171003817100381710038171198911003817100381710038171003817
1minus(119902119901)
Bminus((2120573+2+119889)119902minus119904)120573
infininfin (R119889+1
+ )
10038171003817100381710038171198911003817100381710038171003817
119902119901
B119904120573
119902119902(R119889+1
+ )
(74)
10038171003817100381710038171198911003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
10038171003817100381710038171198911003817100381710038171003817
1minus(119902119901)
Bminus((2120573+2+119889)119902minus119904)120573
infininfin (R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
119902119901
H119904119902120573(R119889+1+
) (75)
where 119901 = 119902(2120573 + 2 + 119889)(2120573 + 2 + 119889 minus 119902119904)
Proof By choosing 119886 = 119904 gt 0 minus119887 = 119904 minus (119889 + 2120573 + 2)119902 lt 01199021 = 119902 and 1199022 = infin we deduce (74) from the relations (70)and (67) In the same way we deduce (75) from the relations(70) and (68)
4 Generalized Heat Equation
41 Characterization for the Weinstein-Besov Spaces TheWeinstein heat equation reads
120597119905119906 (119905 119909) minus Δ 120573119906 (119905 119909) = 119891 (119905 119909) (119905 119909) isin [0infin) timesR119889+1
+
119906|119905=0 = 119892
(76)
We introduce the Weinstein heat semigroup 119867120573(119905) for theWeinstein-Laplace operator
119867120573 (119905) 119892 (119909) =
int
R119889+1+
Γ120573 (119905 119909 119910) 119892 (119910) 119889120583120573 (119910) if 119905 gt 0
119892 (119909) if 119905 = 0(77)
where Γ120573 is the Weinstein heat kernel defined by
Γ120573 (119905 119909 119910) = 120591119909 (119864(120573)
119905) (119910) (78)
where
119864(120573)
119905(119910) =
2
1205871198892Γ (120573 + 1) (4119905)
120573+1+1198892119890minus11991024119905 (79)
Thus
119867120573 (119905) 119892 (119909) = 119892lowast119882119864(120573)
119905 (119909) (80)
In practice we use the integral formulation of (76)
119906 (119905 119909) = 119867120573 (119905) 119892 (119909) + 119866120573 (119891) (119905 119909)
= 119867120573 (119905) 119892 (119909) + int
119905
0
119867120573 (119905 minus 119904) 119891 (119904 119909) 119889119904
(81)
Remark 25 The function 119864(120573)119905
is the Gauss kernel associatedwith Weinstein operators This function satisfies
forall120585 isin R119889+1
+ F119882 (119864
(120573)
119905) (120585) = 119890
minus1199051205852
(82)
Proposition 26 Let 1 le 119901 le 119903 le infin and let 119891 isin 119871119901
120573(R119889+1
+)
Then the operator 119867120573(119905) maps 119871119901
120573(R119889+1
+) continuously to
119871119903
120573(R119889+1
+) and
10038171003817100381710038171003817119867120573 (119905) 119891
10038171003817100381710038171003817119871119903120573(R119889)
le 119862119905minus((119889+2120573+2)2)(1119901minus1119903)1003817
1003817100381710038171198911003817100381710038171003817119871119901
120573(R119889)
(83)
Moreover1003817100381710038171003817100381710038171003817
(minusΔ 120573)
1205752
119867120573 (119905) 119891
1003817100381710038171003817100381710038171003817119871119903120573(R119889)
le 119862119905minus1205752minus((119889+2120573+2)2)(1119901minus1119903)1003817
1003817100381710038171198911003817100381710038171003817119871119901
120573(R119889)
(84)
for all 120575 gt 0
Proof It follows from the relations (80) and (29) combinedwith scaling property of the kernel 119864(120573)
119905
In this section we prove estimates for the Weinstein heatsemigroupThese estimates are based on the following result
Lemma 27 Let C be an annulus Positive constants 119888 and 119862exist such that for any 119901 in [1infin] and any couple (119905 120582) ofpositive real numbers one has
suppF119882 (119906) sub 120582C 997904rArr
10038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
le 119862119890minus1198881199051205822
119906119871119901
120573(R119889+1+
)
(85)
8 Journal of Function Spaces and Applications
Proof We again consider a function Θ in 119863(R119889+1
+ 0) the
value of which is identically 1 in neighborhood of annulusCWe can also assume without loss of generality that 120582 = 1 Wethen have
119867120573 (119905) 119906 = 119892 (119905 sdot) lowast119882119906 (86)where
119892 (119905 sdot) = Fminus1
119882(Θ (120585) 119890
minus1199051205852
) (87)
The lemma is proved provided that we can find positive realnumbers 119888 and 119862 such that
forall119905 gt 01003817100381710038171003817119892 (119905 sdot)
10038171003817100381710038171198711120573(R119889+1+
)le 119862119890
minus119888119905 (88)
To begin we perform integrations by parts in (87) We get1003816100381610038161003816119892 (119905 119909)
1003816100381610038161003816=
1
119888120573
(1 + 1199092)
minus(119889+[2120573]+3)
times int
R119889+1+
Λ (119909 120585) (119868119889 minus Δ 120573)
119889+[2120573]+3
times (Θ (120585) 119890minus1199051205852
) 119889120583120573 (120585)
(89)
Using Leibnizrsquos formula we obtain1003816100381610038161003816119892 (119905 119909)
1003816100381610038161003816le 119862(1 + 119909
2)
minus(119889+[2120573]+3)
119890minus119888119905 (90)
and (88) follows
For any interval 119868 of R (bounded or unbounded) wedefine themixed space-time 119871119901(119868 119871119902
120573(R119889+1
+)) Banach space of
(classes of) measurable functions 119906 119868 rarr 119871119902
120573(R119889+1
+) such
that 119906119871119901(119868119871
119902
120573(R119889+1+
))lt infin with
119906119871119901(119868119871119902
120573(R119889+1+
))= (int
119868
119906 (119905 sdot)119901
119871119902
120573(R119889+1+
)119889119905)
1119901
if 1 le 119901 119902 lt infin
119906119871infin(119868119871119902
120573(R119889+1+
))= ess sup
119905isin119868
119906 (119905 sdot)119871119902
120573(R119889+1+
) if 1 le 119902 lt infin
(91)Corollary 28 Let C be an annulus and 120582 a positive realnumber Let 1199060 (resp 119891 = 119891(119905 119909)) satisfy suppF119882(1199060) sub 120582C(resp suppF119882(119891(119905 sdot)) sub 120582C for all 119905 in [0 119879]) Consider 119906 asolution of
120597119905119906 minus Δ 120573119906 = 0 119906|119905=0 = 1199060 (92)and V a solution of
120597119905V minus Δ 120573V = 119891 (119905 sdot) V|119905=0 = 0 (93)There exist positive constants 119888 and 119862 depending only on Csuch that for any 1 le 119886 le 119887 le infin and 1 le 119901 le 119902 le infin we have
119906119871119902([0119879]119871119887120573(R119889+1+
))le 119862120582
(119889+2120573+2)(1119886minus1119887)120582minus21199021003817
1003817100381710038171199060
1003817100381710038171003817119871119886120573(R119889+1+
)
V119871119902([0119879]119871119887120573(R119889+1+
))le 119862120582
minus2(1+1119902minus1119901)120582(119889+2120573+2)(1119886minus1119887)
times10038171003817100381710038171198911003817100381710038171003817119871119901([0119879]119871119886
120573(R119889+1+
))
(94)
Proof It suffices to use the fact that
119906 (119905 sdot) = 119867120573 (119905) 1199060 V (119905 sdot) = int119905
0
119867120573 (119905 minus 119904) 119891 (119904 sdot) 119889119904
(95)
Combining Lemma 27 and Youngrsquos inequality (29) withscaling property of the kernel 119864(120573)
119905now yields the result
Theorem 29 Let 119904 be a positive real number and (119901 119903) isin
[1infin]2 A constant 119862 exists which satisfies the following
property For 119906 isin Bminus2119904120573
119901119903 (R119889+1
+) one has
119862minus1119906
Bminus2119904120573
119901119903(R119889+1+
)le
10038171003817100381710038171003817100381710038171003817
10038171003817100381710038171003817119905119904119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
10038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
le 119862119906Bminus2119904120573
119901119903(R119889+1+
)
(96)
To prove this result we need the following lemma
Lemma 30 There exist two positive constants 120581 and 119862
depending only on 120593 such that for all 1 le 119901 le infin 120591 ge 0 and119895 isin Z one has
10038171003817100381710038171003817Δ 119895 (119867120573 (120591) 119906)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862119890
minus1205812211989512059110038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
) (97)
Proof The result follows immediately by applying Lemma 27and because Δ 119895(119867120573(120591))119906 = (119867120573(120591)Δ 119895)119906
Proof of Theorem 29 Using Lemma 30 and considering thefact that the operator Δ 119895 commutes with the operator 119867120573(119905)
and the definition of the homogeneous Weinstein-Besov(semi) norm we get
10038171003817100381710038171003817119905119904119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862119906
Bminus2119904120573
119901119903(R119889+1+
)sum
119895isinZ
11990511990422119895119904119890minus12058111990522119895
119888119903119895
(98)
where (119888119903119895)119895isinZ denotes as in all this proof a generic elementof the unit sphere of 119897119903(Z) In the case when 119903 = infin therequired inequality comes immediately from the followingeasy result For any positive 119904 we have
sup119905gt0
sum
119895isinZ
11990511990422119895119904119890minus12058111990522119895
lt infin (99)
In the case 119903 lt infin using the Holder inequality with theweight 22119895119904119890minus1205811199052
2119895
(99) and the Fubini theorem we obtain
int
infin
0
11990511990311990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)
119889119905
119905
le 119862119906119903
Bminus2119904120573
119901119903(R119889+1+
)int
infin
0
(sum
119895isinZ
11990511990422119895119904119890minus12058111990522119895
)
119903minus1
times (sum
119895isinZ
11990511990422119895119904119890minus12058111990522119895
119888119903
119903119895)
119889119905
119905
Journal of Function Spaces and Applications 9
le 119862119906119903
Bminus2119904120573
119901119903(R119889+1+
)int
infin
0
(sum
119895isinZ
11990511990422119895119904119890minus12058111990522119895
119888119903
119903119895)
119889119905
119905
le 119862119906119903
Bminus2119904120573
119901119903(R119889+1+
)sum
119895isinZ
119888119903
119903119895int
infin
0
(11990511990422119895119904119890minus12058111990522119895
)
119889119905
119905
le 119862Γ (119904) 119906119903
Bminus2119904120573
119901119903(R119889+1+
)
(100)
In order to prove the other inequality let us observe thatfor any 119904 greater than minus1 we have
Δ 119895119906 =
1
Γ (119904 + 1)
int
infin
0
119905119904(minusΔ 120573)
119904+1
119867120573 (119905) Δ 119895119906 119889119905 (101)
Then Lemma 30 Proposition 9 and the fact that the operatorΔ 119895 commutes with the operator119867120573(119905) lead to the following
10038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862int
infin
0
11990511990422119895(119904+1)
119890minus1205811199052211989510038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889119905
(102)
In the case 119903 = infin we simply write
10038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862(sup
119905gt0
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
times int
infin
0
22119895(119904+1)
119890minus12058111990522119895
119889119905
le 11986222119895119904(sup119905gt0
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
(103)
In the case 119903 lt infin Holderrsquos inequality with the weight 119890minus12058111990522119895
gives
(int
infin
0
119905119904119890minus1205811199052211989510038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889119905)
119903
le 1198622minus2119895(119903minus1)
int
infin
0
119905119903119904119890minus1205811199052211989510038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)119889119905
(104)
Thanks to (99) and Fubinirsquos theorem we infer from (102) that
sum
119895isinZ
2minus211989511990311990410038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)le 119862int
infin
0
11990511990311990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)
119889119905
119905
(105)
The theorem is proved
Second Proof ofTheorem 29We only consider the case 1 le 119903 ltinfinThe case 119903 = infin can be shown similarlyWe first prove that
119862minus1119906
Bminus2119904120573
119901119903(R119889+1+
)le
10038171003817100381710038171003817100381710038171003817
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
10038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
(106)
It is easy to see that
Δ 119895119906 = 120594119895lowast119882119864(120573)
2minus2119895lowast119882119906
(107)
where 120594119895 = Fminus1
119882(120593(2
minus119895120585)119890
2minus21198951205852
) and119864(120573)2minus2119895
is the Gauss kernelassociated with Weinstein operators By relation (29) we get
10038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le
10038171003817100381710038171003817120594119895
100381710038171003817100381710038171198711120573(R119889+1+
)
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
) (108)
As10038171003817100381710038171003817120594119895
100381710038171003817100381710038171198711120573(R119889+1+
)= int
R119889+1+
100381610038161003816100381610038161003816F
minus1
119882(120593 (120585) 119890
1205852
)
100381610038161003816100381610038161003816119889120583120573 (120585) lt infin (109)
we obtain10038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
) (110)
Moreover simple calculations give that
119864(120573)
2minus2119895lowast119882119906 = 119867120573 (2
minus4119895minus 119905
2) (119864
(120573)
1199052lowast119882119906)
(111)
Thus from Proposition 26 it follows that100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
100381710038171003817100381710038171003817119864(120573)
1199052lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1
+ )
(112)
for any 119905 isin [2minus119895minus1 2minus119895] which implies that
sum
119895isinZ
2minus211990411989511990310038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)
le 119862 sum
119895isinZ
int
2minus119895
2minus119895minus1(119905
2119904100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903119889119905
119905
le 119862int
infin
0
(1199052119904100381710038171003817100381710038171003817119864(120573)
1199052lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903119889119905
119905
le 119862int
infin
0
(11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903119889119905
119905
(113)
where we have used the fact that 119864(120573)1199052lowast119882119906 = 119867120573(119905
2)119906
We now prove that10038171003817100381710038171003817100381710038171003817
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
10038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
le 119862119906Bminus2119904120573
119901119903(R119889+1+
) (114)
Indeed one has
119864(120573)
2minus2119895lowast119882119906 = sum
119899isinZ
119864(120573)
2minus2119895lowast119882Δ 119899+119895119906 (115)
Arguing as above we have100381710038171003817100381710038171003817119864(120573)
1199052lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1
+ )
(116)
for any 119905 isin [2minus119895 21minus119895] Thus10038171003817100381710038171003817100381710038171003817
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
10038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
= 2
100381710038171003817100381710038171003817100381710038171003817
1003817100381710038171003817100381710038171199052119904119864(120573)
1199052lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)
100381710038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
le 119862 sum
119895isinZ
int
21minus119895
2minus119895(2
minus2119895119904100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903119889119905
119905
le 119862 sum
119895isinZ
(2minus2119895119904
sum
119899isinZ
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
(117)
10 Journal of Function Spaces and Applications
On the other hand it is easy to see that100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)le 1198622
minus211989911990410038171003817100381710038171003817Δ 119899+119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
) (118)
for any 119904 gt 0 For 0 lt 1199041 lt 119904 lt 1199042 and by using theMinkowskiinequality we have
sum
119895isinZ
(2minus2119895119904
sum
119899isinZ
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
le sum
119895isinZ
(2minus2119895119904
0
sum
minusinfin
2minus21198991199041
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
+ sum
119895isinZ
(2minus2119895119904
sum
119899isinN
2minus21198991199042
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
le 119862(
0
sum
minusinfin
2minus2119899(119904
1minus119904)(sum
119895isinZ
(2minus2(119899+119895)11990311990410038171003817
100381710038171003817Δ 119899+119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
)
1119903
)
119903
+ 119862(sum
N
2minus2119899(119904
2minus119904)(sum
119895isinZ
(2minus2(119899+119895)11990311990410038171003817
100381710038171003817Δ 119899+119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
)
1119903
)
119903
le 119862 sum
119895isinZ
2minus211989511990311990410038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)
(119)
The result is immediately from (117) and (119)
42 Embedding Sobolev Theorems
Theorem 31 Let 1 lt 119901 lt infin and let 0 lt 119904 lt (119889 + 2120573 +
2)119901There exists a positive constant119862 such that for all function119891 isin
H119904
119901120573(R119889+1
+) one has
10038171003817100381710038171198911003817100381710038171003817119871119902
120573(R119889+1+
)le 119862
10038171003817100381710038171198911003817100381710038171003817
1minus120579
H119904119901120573(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
120579
B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
) (120)
where 120579 = 119904119901(119889+2120573+2) and 119902 = 119901(119889+2120573+2)(119889+2120573+2minus119901119904)
Proof Bydensity we can suppose that119891belongs toSlowast(R119889+1
)It is easy to see that
119891 = int
infin
0
119867120573 (119905) Δ 120573119891119889119905(121)
and decompose the integral in two parts as follows
119891 = int
119860
0
119867120573 (119905) Δ 120573119891119889119905 + int
infin
119860
119867120573 (119905) Δ 120573119891119889119905(122)
where 119860 is a constant to be fixed laterOn the other hand byTheorem 29 we obtain10038171003817100381710038171003817119867120573 (119905) Δ 120573119891
10038171003817100381710038171003817119871infin120573(R119889+1+
)
le
119862
1199051minus(12)(119904minus(119889+2120573+2)119901)
10038171003817100381710038171198911003817100381710038171003817B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
)
(123)
Therefore after integrating we get
int
infin
119860
10038171003817100381710038171003817119867120573 (119905) Δ 120573119891
10038171003817100381710038171003817119871infin120573(R119889+1+
)119889119905
le 119860(12)(119904minus(119889+2120573+2)119901)1003817
1003817100381710038171198911003817100381710038171003817B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
)
(124)
On the other hand denoting 119892 = (minusΔ 120573)1199042119891 we have
119867120573 (119905) Δ 120573119891 =
1
(minus119905)1minus1199042
119867120573 (119905) (minus119905Δ 120573)
1minus1199042
119892 (125)
We proceed as in [8] we prove that1003816100381610038161003816100381610038161003816
119867120573 (119905) (minus119905Δ 120573)
1minus1199042
119892 (119909)
1003816100381610038161003816100381610038161003816
le 119862 (119904)119872120573 (119892) (119909) (126)
where119872120573(119892) is a maximal function of 119892 associated with theWeinstein operators (cf [12])
This leads to100381610038161003816100381610038161003816100381610038161003816
int
119860
0
119867120573 (119905) Δ 120573119891 (119909) 119889119905
100381610038161003816100381610038161003816100381610038161003816
le 1198621198601199042119872120573 (119892) (119909) (127)
In conclusion we get10038161003816100381610038161003816100381610038161003816
int
infin
0
119867120573 (119905) Δ 120573119891 (119909) 119889119905
10038161003816100381610038161003816100381610038161003816
le 119862 (1198601199042119872120573 (119892) (119909)
+119860(12)(119904minus(119889+2120573+2)119901)1003817
1003817100381710038171198911003817100381710038171003817B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
))
(128)
and the choice of 119860 such that
119860(119889+2120573+2)2119901
119872120573 (119892) (119909) =10038171003817100381710038171198911003817100381710038171003817B119904minus(119889+2120573+2)119901120573
infininfin (R119889+1+
)(129)
ensures that10038161003816100381610038161003816100381610038161003816
int
infin
0
119867120573 (119905) Δ 120573119891 (119909) 119889119905
10038161003816100381610038161003816100381610038161003816
le 119862(119872120573(119892)(119909))
1minus(119901119904(119889+2120573+2))10038171003817100381710038171198911003817100381710038171003817
119901119904(119889+2120573+2)
B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
)
(130)
Finally taking the 119871119902120573norm with 119902 = 119901(119889 + 2120573 + 2)(119889 + 2120573 +
2minus119901119904) ends the proof thanks to the fact themaximal function119872120573 is bounded of 119871119902
120573(R119889+1
+) into itself for 119902 gt 1
Theorem 32 Let 1 lt 119901 lt 119902 lt infin For all function 119891 such that119891 isin
H1199041
119901120573(R119889+1
+)⋂
Bminus120573120573
infininfin(R119889+1
+) one has
10038171003817100381710038171198911003817100381710038171003817H119904119901120573(R119889+1+
)le 119862
10038171003817100381710038171198911003817100381710038171003817
120579
H1199041
119901120573(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
1minus120579
Bminus120573120573
infininfin(R119889+1
+) (131)
where 120579 = 119901119902 119904 = 1205791199041 minus (1 minus 120579)120573 with 120573 gt 0 minus120573 lt 119904 lt 1199041
Proof It suffices to prove that1003817100381710038171003817100381710038171003817
(minusΔ 120573)
(119904minus1199041)2
119891
1003817100381710038171003817100381710038171003817119871119902
120573(R119889+1+
)
le 11986210038171003817100381710038171198911003817100381710038171003817
120579
119871119901
120573(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
1minus120579
Bminus120573minus1199041120573
infininfin (R119889+1+
)
(132)
Journal of Function Spaces and Applications 11
Indeed we use the following identity (which may be easilyproven by taking the Weinstein transform in 119909 of both sides)
(minusΔ 120573)
minus1205752
119891 (119909) =
1
Γ (1205752)
int
infin
0
1199051205752minus1
119867120573 (119905) 119891 (119909) 119889119905 (133)
with 120575 = 1199041 minus 119904 gt 0We decompose the integral in two parts as follows
(minusΔ 120573)
minus1205752
119891 (119909) =
1
Γ (1205752)
int
119879
0
1199051205752minus1
119867120573 (119905) 119891 (119909) 119889119905
+
1
Γ (1205752)
int
infin
119879
1199051205752minus1
119867120573 (119905) 119891 (119909) 119889119905
(134)
where 119879 is a constant to be fixed laterWe proceed as in [8] we obtain
10038161003816100381610038161003816119867120573 (119905) 119891 (119909)
10038161003816100381610038161003816le 119862119872120573 (119891) (119909) (135)
On the other hand we use Theorem 29 and the fact that 119891belongs to Bminus120573minus119904
1120573
infininfin(R119889+1
+) to deduce that
10038161003816100381610038161003816119867120573 (119905) 119891 (119909)
10038161003816100381610038161003816le 119862119905
(minus120573minus1199041)210038171003817100381710038171198911003817100381710038171003817Bminus120573minus1199041120573
infininfin (R119889+1+
) (136)
Thus by applying the preceding estimates on the right part of(134) we obtain
1003816100381610038161003816100381610038161003816
(minusΔ 120573)
minus1205752
119891 (119909)
1003816100381610038161003816100381610038161003816
le
1198621
Γ (1205752)
1198791205752119872120573 (119891) (119909)
+
1198622
Γ (1205752)
119879(120575minus120573minus119904
1)210038171003817100381710038171198911003817100381710038171003817Bminus120573minus1199041120573
infininfin (R119889+1+
)
(137)
We fix now
119879 = (
10038171003817100381710038171198911003817100381710038171003817Bminus120573minus1199041120573
infininfin (R119889+1+
)
119872120573 (119891) (119909)
)
2(120573+1199041)
(138)
We obtain
1003816100381610038161003816100381610038161003816
(minusΔ120573)
minus1205752
119891 (119909)
1003816100381610038161003816100381610038161003816
le
1198621 + 1198622
Γ (1205752)
(119872120573(119891)(119909))
12057910038171003817100381710038171198911003817100381710038171003817
1minus120579
Bminus120573minus1199041120573
infininfin (R119889+1+
)
(139)
Thus we deduce that1003817100381710038171003817100381710038171003817
(minusΔ120573)
minus1205752
119891
1003817100381710038171003817100381710038171003817119871119902
120573(R119889+1+
)
le
1198621 + 1198622
Γ (1205752)
10038171003817100381710038171003817119872120573 (119891)
10038171003817100381710038171003817
120579
119871119901
120573(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
1minus120579
Bminus120573minus1199041120573
infininfin (R119889+1+
)
(140)
To conclude we used the fact that the maximal function119872120573
is bounded of 119871119902120573(R119889+1
+) into itself for 119902 gt 1
43 Estimates in Generalized Besov Spaces For any interval 119868ofR (bounded or unbounded) and a normed space 119865(R119889+1
+)
we define the mixed space-time 119871119901(119868 119865(R119889+1
+)) space of
(classes of) measurable functions 119906 119868 rarr 119865(R119889+1
+) such that
||119906||119871119901(119868119865(R119889+1+
)) lt infin with
119906119871119901(119868119865(R119889+1+
)) = (int
119868
119906 (119905 sdot)119901
119865(R119889+1+
)119889119905)
1119901
if 1 le 119901 lt infin
119906119871infin(119868119865(R119889+1+
)) = ess sup119905isin119868
119906 (119905 sdot)119865(R119889+1+
)
(141)
For any interval 119868 of R (bounded or unbounded) anda Banach space 119883 we define the mixed space-time 119862(119868119883)space of continuous functions 119868 rarr 119883 When 119868 is bounded119862(119868119883) is a Banach space with the norm of 119871infin(119868 119883)
Theorem 33 Let 119904 isin R and 1 le 119901 119902 119903 le infin Let 119879 gt 0 119892 isin
B119904120573
119901119903(R119889+1
+) and119891 in 119871119902((0 119879) B
119904minus2+(2119902)120573
119901119903 (R119889+1
+)) Then (76)
has a unique solution
119906 isin 119871119902((0 119879)
B119904+(2119902)120573
119901119903(R
119889+1
+))
⋂119871infin((0 119879)
B119904120573
119901119903(R
119889+1
+))
(142)
and there exists a constant 119862 such that for all 1199021 isin [119902infin] onehas
1199061198711199021 ((0119879)B
119904+(21199021)120573
119901119903(R119889+1+
))
le 119862(10038171003817100381710038171198921003817100381710038171003817B119904120573
119901119903(R119889+1+
)+10038171003817100381710038171198911003817100381710038171003817119871119902((0119879)B
119904minus2+(2119902)120573
119901119903(R119889+1+
)))
(143)
If in addition 119903 lt infin then 119906 isin 119862([0 119879] B119904120573
119901119903(R119889+1
+))
Proof Since 119892 and 119891 are temperate distributions (76) has aunique solution 119906 in S1015840
((0 119879) timesR119889+1
+) which satisfies
F119882 (119906) (119905 120585) = 119890minus1199051205852
F119882 (119892) (120585)
+ int
119905
0
119890(120591minus119905)120585
2
F119882 (119891) (120591 120585) 119889120591
(144)
Next we notice that applying Δ 119895 to (76) and using formula(81) yield
Δ 119895119906 (119905 sdot) = 119867120573 (119905) Δ 119895119892 + int
119905
0
119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot) 119889120591(145)
Therefore
10038171003817100381710038171003817Δ 119895119906 (119905 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le
10038171003817100381710038171003817119867120573(119905)Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+ int
119905
0
10038171003817100381710038171003817119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591
(146)
12 Journal of Function Spaces and Applications
By virtue of Lemma 30 we thus have for some 120581 gt 0
10038171003817100381710038171003817Δ 119895119906(119905 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
le 119862[119890minus1205812211989511990510038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+ int
119905
0
119890minus12058122119895(119905minus120591) 10038171003817
100381710038171003817Δ 119895119891 (120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591]
(147)
Applying convolution inequalities we get
10038171003817100381710038171003817Δ 119895119906
100381710038171003817100381710038171198711199021 ((0119879)119871
119901
120573(R119889+1+
))
le 119862[
[
((
1 minus 119890minus120581119879119902122119895
120581119902122119895
)
11199021
)
10038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+((
1 minus 119890minus120581119879119902222119895
120581119902222119895
)
11199022
)
10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119902((0119879)119871
119901
120573(R119889+1+
))
]
]
(148)
with 11199022 = 1+ 11199021 minus1119902 Finally taking the 119897119903(Z) norm we
conclude that (with the usual convention if 119903 = infin)
1199061198711199021 ((0119879)B
119904+(21199021)120573
119901119903(R119889+1+
))
le 119862[
[
sum
119895isinZ
((
1 minus 119890minus120581119879119902122119895
120581119902122119895
)
1199031199021
)(211989511990410038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
]
]
1119903
+ 119862[
[
sum
119895isinZ
((
1 minus 119890minus120581119879119902222119895
120581119902222119895
)
1199031199022
)
times (2119895(119904minus2+2119902)10038171003817
100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119902(0119879119871
119901
120573(R119889+1+
))
119903
]
]
1119903
(149)
which insures that 119906 isin 119871119902((0 119879)
B119904+(2119902)120573
119901119903 (R119889+1
+))
⋂119871infin((0 119879)
B119904120573
119901119903(R119889+1
+)) and yields the desired inequality
Since 119906 belongs to 119862([0 119879]B119904120573
119901119903(R119889+1
+)) in the case where
119903 is finite may be easily deduced from the density ofSlowast(R
119889+1)⋂
B119904120573
119901119903(R119889+1
+) in B
119904120573
119901119903(R)
Theorem 34 Let 119904 isin R 119879 gt 0 and 1 le 119901 119902 119903 le infinOne supposes that 119892 isin 119861
119904120573
119901119903(R119889+1
+) and 119891 isin 119871
119902((0 119879)
119861119904minus2+(2119902)120573
119901119903 (R119889+1
+)) Then (76) has a unique solution 119906 belong-
ing to
119871119902((0 119879) 119861
119904+(2119902)120573
119901119903(R
119889+1
+))⋂119871
infin((0 119879) 119861
119904120573
119901119903(R
119889+1
+))
(150)
and there exists a constant 119862 such that for all 119902 le 1199021 le infin
1199061198711199021 ((0119879)119861
119904+(21199021)120573
119901119903(R119889+1+
))
le 119862 [ (1 + 11987911199021)10038171003817100381710038171198921003817100381710038171003817119861119904120573
119901119903(R119889+1+
)
+ (1 + 1198791+1119902
1minus1119902
)10038171003817100381710038171198911003817100381710038171003817119871119902((0119879)119861
119904minus2+(2119902)120573
119901119903(R119889+1+
))]
(151)
If in addition 119903 lt infin then 119906 isin 119862([0 119879] 119861119904120573119901119903(R119889+1
+))
Proof Since 119892 119891 are tempered (76) has a unique solution 119906in S1015840
((0 119879) timesR119889+1
+) satisfying
F119882 (119906) (119905 120585) = 119890minus1199051205852
F119882 (119892) (120585)
+ int
119905
0
119890(120591minus119905)120585
2
F119882 (119891) (120591 120585) 119889120591
(152)
Hence applying Δ 119895 119895 ge 0 to (81) we see that
Δ 119895119906 (119905 sdot) = 119867120573 (119905) Δ 119895119892 + int
119905
0
119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot) 119889120591(153)
and thus by Lemma 30 we can deduce that10038171003817100381710038171003817Δ 119895119906 (119905 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
le
10038171003817100381710038171003817119867120573(119905)Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)+ int
119905
0
10038171003817100381710038171003817119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591
le 119862[119890minus1205812211989511990510038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+int
119905
0
119890minus12058122119895(119905minus120591)10038171003817
100381710038171003817Δ 119895119891(120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591]
(154)
Then it follows from convolution inequalities thatΔ 1198951199061198711199021 ((0119879)119871
119901
120573(R119889+1+
))is dominated by
(
1 minus 119890minus120581119879119902122119895
120581119902122119895
)
11199021
10038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119861119904120573
119901119903(R119889+1+
)
+ (
1 minus 119890minus120581119879119902222119895
120581119902222119895
)
11199022
10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119902((0119879)119871
119901
120573(R119889+1+
))
(155)
with 11199022 = 1 + 11199021 minus 1119902 Moreover similarly as above wecan obtain that
1003817100381710038171003817Δminus1119906(119905 sdot)
1003817100381710038171003817119871119901
120573(R119889+1+
)le1003817100381710038171003817Δminus1119892
1003817100381710038171003817119871119901
120573(R119889+1+
)
+ int
119905
0
1003817100381710038171003817Δminus1119891 (120591 sdot)
1003817100381710038171003817119871119901
120573(R119889+1+
)119889120591
(156)
and thus if 1 le 119902 le 1199021 le infin1003817100381710038171003817Δminus1119906
10038171003817100381710038171198711199021 ((0119879)119871
119901
120573(R119889+1+
))
le 119862(119879111990211003817100381710038171003817Δminus1119892
1003817100381710038171003817119871119901
120573(R119889+1+
)+ 119879
111990221003817100381710038171003817Δminus1119891
1003817100381710038171003817119871119902((0119879)119871
119901
120573(R119889+1+
)))
(157)
Journal of Function Spaces and Applications 13
Finally taking the 119897119903-normwith respect to 119895 in (155) and (157)with the usual convention if 119903 = infin we can deduce the desiredestimate
Acknowledgment
Theauthor gratefully acknowledges theDeanship of ScientificResearch at the University of Taibah The author is deeplyindebted to the referee for providing constructive commentsand help in improving the contents of this paper
References
[1] Z Ben Nahia and N Ben Salem ldquoSpherical harmonics andapplications associated with the Weinstein operatorrdquo in Pro-ceedings of the International Conference on PotentialTheory heldin Kouty Czech Republic (ICPT rsquo94) pp 235ndash241 1996
[2] Z Ben Nahia and N Ben Salem ldquoOn a mean value propertyassociated with the Weinstein operatorrdquo in Proceedings of theInternational Conference on Potential Theory held in KoutyCzech Republic (ICPT rsquo94) pp 243ndash253 1996
[3] M Brelot ldquoEquation de Weinstein et potentiels de MarcelRieszrdquo in Seminaire de Theorie de Potentiel Paris No 3 vol 681of Lecture Notes in Mathematics pp 18ndash38 Springer BerlinGermany 1978
[4] H Mejjaoli and M Salhi ldquoUncertainty principles for theweinstein transformrdquo Czechoslovak Mathematical Journal vol61 no 4 pp 941ndash974 2011
[5] H Mejjaoli and A Ould Ahmed Salem ldquoWeinstein Gabortransform and applicationsrdquo Advanced Studies in Pure Mathe-matics vol 2 no 3 pp 203ndash210 2012
[6] H Mejjaoli ldquoBesov spaces associated withthe Weinstein opera-tor and applicationsrdquo In press
[7] T Kawazoe and H Mejjaoli ldquoGeneralized Besov spaces andtheir applicationsrdquo Tokyo Journal of Mathematics vol 35 no 2pp 297ndash320 2012
[8] H Mejjaoli ldquoLittlewood-Paley decomposition associated withthe Dunkl operators and paraproduct operatorsrdquo Journal ofInequalities in Pure and Applied Mathematics vol 9 no 4 pp1ndash25 2008
[9] H Mejjaoli and N Sraeib ldquoGeneralized sobolev spaces inquantum calculus and applicationsrdquo Journal of Inequalities andSpecial Functions vol 1 no 4 pp 43ndash64 2012
[10] H Mejjaoli ldquoGeneralized homogeneous Besov spaces and theirapplicationsrdquo Serdica Mathematical Journal vol 38 no 4 pp575ndash614 2012
[11] H Triebel Interpolation Theory Functions Spaces DifferentialOperators North-Holland AmsterdamThe Netherlands 1978
[12] V S Guliev ldquoOn maximal function and fractional integralassociated with the Bessel differential operatorrdquo MathematicalInequalities and Applications vol 6 no 2 pp 317ndash330 2003
Submit your manuscripts athttpwwwhindawicom
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
MathematicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Mathematical Problems in Engineering
Hindawi Publishing Corporationhttpwwwhindawicom
Differential EquationsInternational Journal of
Volume 2014
Applied MathematicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Probability and StatisticsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Mathematical PhysicsAdvances in
Complex AnalysisJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
OptimizationJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
CombinatoricsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
International Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Operations ResearchAdvances in
Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Function Spaces
Abstract and Applied AnalysisHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
International Journal of Mathematics and Mathematical Sciences
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Algebra
Discrete Dynamics in Nature and Society
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Decision SciencesAdvances in
Discrete MathematicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom
Volume 2014 Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Stochastic AnalysisInternational Journal of
8 Journal of Function Spaces and Applications
Proof We again consider a function Θ in 119863(R119889+1
+ 0) the
value of which is identically 1 in neighborhood of annulusCWe can also assume without loss of generality that 120582 = 1 Wethen have
119867120573 (119905) 119906 = 119892 (119905 sdot) lowast119882119906 (86)where
119892 (119905 sdot) = Fminus1
119882(Θ (120585) 119890
minus1199051205852
) (87)
The lemma is proved provided that we can find positive realnumbers 119888 and 119862 such that
forall119905 gt 01003817100381710038171003817119892 (119905 sdot)
10038171003817100381710038171198711120573(R119889+1+
)le 119862119890
minus119888119905 (88)
To begin we perform integrations by parts in (87) We get1003816100381610038161003816119892 (119905 119909)
1003816100381610038161003816=
1
119888120573
(1 + 1199092)
minus(119889+[2120573]+3)
times int
R119889+1+
Λ (119909 120585) (119868119889 minus Δ 120573)
119889+[2120573]+3
times (Θ (120585) 119890minus1199051205852
) 119889120583120573 (120585)
(89)
Using Leibnizrsquos formula we obtain1003816100381610038161003816119892 (119905 119909)
1003816100381610038161003816le 119862(1 + 119909
2)
minus(119889+[2120573]+3)
119890minus119888119905 (90)
and (88) follows
For any interval 119868 of R (bounded or unbounded) wedefine themixed space-time 119871119901(119868 119871119902
120573(R119889+1
+)) Banach space of
(classes of) measurable functions 119906 119868 rarr 119871119902
120573(R119889+1
+) such
that 119906119871119901(119868119871
119902
120573(R119889+1+
))lt infin with
119906119871119901(119868119871119902
120573(R119889+1+
))= (int
119868
119906 (119905 sdot)119901
119871119902
120573(R119889+1+
)119889119905)
1119901
if 1 le 119901 119902 lt infin
119906119871infin(119868119871119902
120573(R119889+1+
))= ess sup
119905isin119868
119906 (119905 sdot)119871119902
120573(R119889+1+
) if 1 le 119902 lt infin
(91)Corollary 28 Let C be an annulus and 120582 a positive realnumber Let 1199060 (resp 119891 = 119891(119905 119909)) satisfy suppF119882(1199060) sub 120582C(resp suppF119882(119891(119905 sdot)) sub 120582C for all 119905 in [0 119879]) Consider 119906 asolution of
120597119905119906 minus Δ 120573119906 = 0 119906|119905=0 = 1199060 (92)and V a solution of
120597119905V minus Δ 120573V = 119891 (119905 sdot) V|119905=0 = 0 (93)There exist positive constants 119888 and 119862 depending only on Csuch that for any 1 le 119886 le 119887 le infin and 1 le 119901 le 119902 le infin we have
119906119871119902([0119879]119871119887120573(R119889+1+
))le 119862120582
(119889+2120573+2)(1119886minus1119887)120582minus21199021003817
1003817100381710038171199060
1003817100381710038171003817119871119886120573(R119889+1+
)
V119871119902([0119879]119871119887120573(R119889+1+
))le 119862120582
minus2(1+1119902minus1119901)120582(119889+2120573+2)(1119886minus1119887)
times10038171003817100381710038171198911003817100381710038171003817119871119901([0119879]119871119886
120573(R119889+1+
))
(94)
Proof It suffices to use the fact that
119906 (119905 sdot) = 119867120573 (119905) 1199060 V (119905 sdot) = int119905
0
119867120573 (119905 minus 119904) 119891 (119904 sdot) 119889119904
(95)
Combining Lemma 27 and Youngrsquos inequality (29) withscaling property of the kernel 119864(120573)
119905now yields the result
Theorem 29 Let 119904 be a positive real number and (119901 119903) isin
[1infin]2 A constant 119862 exists which satisfies the following
property For 119906 isin Bminus2119904120573
119901119903 (R119889+1
+) one has
119862minus1119906
Bminus2119904120573
119901119903(R119889+1+
)le
10038171003817100381710038171003817100381710038171003817
10038171003817100381710038171003817119905119904119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
10038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
le 119862119906Bminus2119904120573
119901119903(R119889+1+
)
(96)
To prove this result we need the following lemma
Lemma 30 There exist two positive constants 120581 and 119862
depending only on 120593 such that for all 1 le 119901 le infin 120591 ge 0 and119895 isin Z one has
10038171003817100381710038171003817Δ 119895 (119867120573 (120591) 119906)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862119890
minus1205812211989512059110038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
) (97)
Proof The result follows immediately by applying Lemma 27and because Δ 119895(119867120573(120591))119906 = (119867120573(120591)Δ 119895)119906
Proof of Theorem 29 Using Lemma 30 and considering thefact that the operator Δ 119895 commutes with the operator 119867120573(119905)
and the definition of the homogeneous Weinstein-Besov(semi) norm we get
10038171003817100381710038171003817119905119904119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862119906
Bminus2119904120573
119901119903(R119889+1+
)sum
119895isinZ
11990511990422119895119904119890minus12058111990522119895
119888119903119895
(98)
where (119888119903119895)119895isinZ denotes as in all this proof a generic elementof the unit sphere of 119897119903(Z) In the case when 119903 = infin therequired inequality comes immediately from the followingeasy result For any positive 119904 we have
sup119905gt0
sum
119895isinZ
11990511990422119895119904119890minus12058111990522119895
lt infin (99)
In the case 119903 lt infin using the Holder inequality with theweight 22119895119904119890minus1205811199052
2119895
(99) and the Fubini theorem we obtain
int
infin
0
11990511990311990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)
119889119905
119905
le 119862119906119903
Bminus2119904120573
119901119903(R119889+1+
)int
infin
0
(sum
119895isinZ
11990511990422119895119904119890minus12058111990522119895
)
119903minus1
times (sum
119895isinZ
11990511990422119895119904119890minus12058111990522119895
119888119903
119903119895)
119889119905
119905
Journal of Function Spaces and Applications 9
le 119862119906119903
Bminus2119904120573
119901119903(R119889+1+
)int
infin
0
(sum
119895isinZ
11990511990422119895119904119890minus12058111990522119895
119888119903
119903119895)
119889119905
119905
le 119862119906119903
Bminus2119904120573
119901119903(R119889+1+
)sum
119895isinZ
119888119903
119903119895int
infin
0
(11990511990422119895119904119890minus12058111990522119895
)
119889119905
119905
le 119862Γ (119904) 119906119903
Bminus2119904120573
119901119903(R119889+1+
)
(100)
In order to prove the other inequality let us observe thatfor any 119904 greater than minus1 we have
Δ 119895119906 =
1
Γ (119904 + 1)
int
infin
0
119905119904(minusΔ 120573)
119904+1
119867120573 (119905) Δ 119895119906 119889119905 (101)
Then Lemma 30 Proposition 9 and the fact that the operatorΔ 119895 commutes with the operator119867120573(119905) lead to the following
10038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862int
infin
0
11990511990422119895(119904+1)
119890minus1205811199052211989510038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889119905
(102)
In the case 119903 = infin we simply write
10038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862(sup
119905gt0
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
times int
infin
0
22119895(119904+1)
119890minus12058111990522119895
119889119905
le 11986222119895119904(sup119905gt0
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
(103)
In the case 119903 lt infin Holderrsquos inequality with the weight 119890minus12058111990522119895
gives
(int
infin
0
119905119904119890minus1205811199052211989510038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889119905)
119903
le 1198622minus2119895(119903minus1)
int
infin
0
119905119903119904119890minus1205811199052211989510038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)119889119905
(104)
Thanks to (99) and Fubinirsquos theorem we infer from (102) that
sum
119895isinZ
2minus211989511990311990410038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)le 119862int
infin
0
11990511990311990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)
119889119905
119905
(105)
The theorem is proved
Second Proof ofTheorem 29We only consider the case 1 le 119903 ltinfinThe case 119903 = infin can be shown similarlyWe first prove that
119862minus1119906
Bminus2119904120573
119901119903(R119889+1+
)le
10038171003817100381710038171003817100381710038171003817
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
10038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
(106)
It is easy to see that
Δ 119895119906 = 120594119895lowast119882119864(120573)
2minus2119895lowast119882119906
(107)
where 120594119895 = Fminus1
119882(120593(2
minus119895120585)119890
2minus21198951205852
) and119864(120573)2minus2119895
is the Gauss kernelassociated with Weinstein operators By relation (29) we get
10038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le
10038171003817100381710038171003817120594119895
100381710038171003817100381710038171198711120573(R119889+1+
)
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
) (108)
As10038171003817100381710038171003817120594119895
100381710038171003817100381710038171198711120573(R119889+1+
)= int
R119889+1+
100381610038161003816100381610038161003816F
minus1
119882(120593 (120585) 119890
1205852
)
100381610038161003816100381610038161003816119889120583120573 (120585) lt infin (109)
we obtain10038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
) (110)
Moreover simple calculations give that
119864(120573)
2minus2119895lowast119882119906 = 119867120573 (2
minus4119895minus 119905
2) (119864
(120573)
1199052lowast119882119906)
(111)
Thus from Proposition 26 it follows that100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
100381710038171003817100381710038171003817119864(120573)
1199052lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1
+ )
(112)
for any 119905 isin [2minus119895minus1 2minus119895] which implies that
sum
119895isinZ
2minus211990411989511990310038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)
le 119862 sum
119895isinZ
int
2minus119895
2minus119895minus1(119905
2119904100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903119889119905
119905
le 119862int
infin
0
(1199052119904100381710038171003817100381710038171003817119864(120573)
1199052lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903119889119905
119905
le 119862int
infin
0
(11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903119889119905
119905
(113)
where we have used the fact that 119864(120573)1199052lowast119882119906 = 119867120573(119905
2)119906
We now prove that10038171003817100381710038171003817100381710038171003817
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
10038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
le 119862119906Bminus2119904120573
119901119903(R119889+1+
) (114)
Indeed one has
119864(120573)
2minus2119895lowast119882119906 = sum
119899isinZ
119864(120573)
2minus2119895lowast119882Δ 119899+119895119906 (115)
Arguing as above we have100381710038171003817100381710038171003817119864(120573)
1199052lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1
+ )
(116)
for any 119905 isin [2minus119895 21minus119895] Thus10038171003817100381710038171003817100381710038171003817
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
10038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
= 2
100381710038171003817100381710038171003817100381710038171003817
1003817100381710038171003817100381710038171199052119904119864(120573)
1199052lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)
100381710038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
le 119862 sum
119895isinZ
int
21minus119895
2minus119895(2
minus2119895119904100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903119889119905
119905
le 119862 sum
119895isinZ
(2minus2119895119904
sum
119899isinZ
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
(117)
10 Journal of Function Spaces and Applications
On the other hand it is easy to see that100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)le 1198622
minus211989911990410038171003817100381710038171003817Δ 119899+119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
) (118)
for any 119904 gt 0 For 0 lt 1199041 lt 119904 lt 1199042 and by using theMinkowskiinequality we have
sum
119895isinZ
(2minus2119895119904
sum
119899isinZ
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
le sum
119895isinZ
(2minus2119895119904
0
sum
minusinfin
2minus21198991199041
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
+ sum
119895isinZ
(2minus2119895119904
sum
119899isinN
2minus21198991199042
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
le 119862(
0
sum
minusinfin
2minus2119899(119904
1minus119904)(sum
119895isinZ
(2minus2(119899+119895)11990311990410038171003817
100381710038171003817Δ 119899+119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
)
1119903
)
119903
+ 119862(sum
N
2minus2119899(119904
2minus119904)(sum
119895isinZ
(2minus2(119899+119895)11990311990410038171003817
100381710038171003817Δ 119899+119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
)
1119903
)
119903
le 119862 sum
119895isinZ
2minus211989511990311990410038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)
(119)
The result is immediately from (117) and (119)
42 Embedding Sobolev Theorems
Theorem 31 Let 1 lt 119901 lt infin and let 0 lt 119904 lt (119889 + 2120573 +
2)119901There exists a positive constant119862 such that for all function119891 isin
H119904
119901120573(R119889+1
+) one has
10038171003817100381710038171198911003817100381710038171003817119871119902
120573(R119889+1+
)le 119862
10038171003817100381710038171198911003817100381710038171003817
1minus120579
H119904119901120573(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
120579
B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
) (120)
where 120579 = 119904119901(119889+2120573+2) and 119902 = 119901(119889+2120573+2)(119889+2120573+2minus119901119904)
Proof Bydensity we can suppose that119891belongs toSlowast(R119889+1
)It is easy to see that
119891 = int
infin
0
119867120573 (119905) Δ 120573119891119889119905(121)
and decompose the integral in two parts as follows
119891 = int
119860
0
119867120573 (119905) Δ 120573119891119889119905 + int
infin
119860
119867120573 (119905) Δ 120573119891119889119905(122)
where 119860 is a constant to be fixed laterOn the other hand byTheorem 29 we obtain10038171003817100381710038171003817119867120573 (119905) Δ 120573119891
10038171003817100381710038171003817119871infin120573(R119889+1+
)
le
119862
1199051minus(12)(119904minus(119889+2120573+2)119901)
10038171003817100381710038171198911003817100381710038171003817B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
)
(123)
Therefore after integrating we get
int
infin
119860
10038171003817100381710038171003817119867120573 (119905) Δ 120573119891
10038171003817100381710038171003817119871infin120573(R119889+1+
)119889119905
le 119860(12)(119904minus(119889+2120573+2)119901)1003817
1003817100381710038171198911003817100381710038171003817B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
)
(124)
On the other hand denoting 119892 = (minusΔ 120573)1199042119891 we have
119867120573 (119905) Δ 120573119891 =
1
(minus119905)1minus1199042
119867120573 (119905) (minus119905Δ 120573)
1minus1199042
119892 (125)
We proceed as in [8] we prove that1003816100381610038161003816100381610038161003816
119867120573 (119905) (minus119905Δ 120573)
1minus1199042
119892 (119909)
1003816100381610038161003816100381610038161003816
le 119862 (119904)119872120573 (119892) (119909) (126)
where119872120573(119892) is a maximal function of 119892 associated with theWeinstein operators (cf [12])
This leads to100381610038161003816100381610038161003816100381610038161003816
int
119860
0
119867120573 (119905) Δ 120573119891 (119909) 119889119905
100381610038161003816100381610038161003816100381610038161003816
le 1198621198601199042119872120573 (119892) (119909) (127)
In conclusion we get10038161003816100381610038161003816100381610038161003816
int
infin
0
119867120573 (119905) Δ 120573119891 (119909) 119889119905
10038161003816100381610038161003816100381610038161003816
le 119862 (1198601199042119872120573 (119892) (119909)
+119860(12)(119904minus(119889+2120573+2)119901)1003817
1003817100381710038171198911003817100381710038171003817B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
))
(128)
and the choice of 119860 such that
119860(119889+2120573+2)2119901
119872120573 (119892) (119909) =10038171003817100381710038171198911003817100381710038171003817B119904minus(119889+2120573+2)119901120573
infininfin (R119889+1+
)(129)
ensures that10038161003816100381610038161003816100381610038161003816
int
infin
0
119867120573 (119905) Δ 120573119891 (119909) 119889119905
10038161003816100381610038161003816100381610038161003816
le 119862(119872120573(119892)(119909))
1minus(119901119904(119889+2120573+2))10038171003817100381710038171198911003817100381710038171003817
119901119904(119889+2120573+2)
B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
)
(130)
Finally taking the 119871119902120573norm with 119902 = 119901(119889 + 2120573 + 2)(119889 + 2120573 +
2minus119901119904) ends the proof thanks to the fact themaximal function119872120573 is bounded of 119871119902
120573(R119889+1
+) into itself for 119902 gt 1
Theorem 32 Let 1 lt 119901 lt 119902 lt infin For all function 119891 such that119891 isin
H1199041
119901120573(R119889+1
+)⋂
Bminus120573120573
infininfin(R119889+1
+) one has
10038171003817100381710038171198911003817100381710038171003817H119904119901120573(R119889+1+
)le 119862
10038171003817100381710038171198911003817100381710038171003817
120579
H1199041
119901120573(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
1minus120579
Bminus120573120573
infininfin(R119889+1
+) (131)
where 120579 = 119901119902 119904 = 1205791199041 minus (1 minus 120579)120573 with 120573 gt 0 minus120573 lt 119904 lt 1199041
Proof It suffices to prove that1003817100381710038171003817100381710038171003817
(minusΔ 120573)
(119904minus1199041)2
119891
1003817100381710038171003817100381710038171003817119871119902
120573(R119889+1+
)
le 11986210038171003817100381710038171198911003817100381710038171003817
120579
119871119901
120573(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
1minus120579
Bminus120573minus1199041120573
infininfin (R119889+1+
)
(132)
Journal of Function Spaces and Applications 11
Indeed we use the following identity (which may be easilyproven by taking the Weinstein transform in 119909 of both sides)
(minusΔ 120573)
minus1205752
119891 (119909) =
1
Γ (1205752)
int
infin
0
1199051205752minus1
119867120573 (119905) 119891 (119909) 119889119905 (133)
with 120575 = 1199041 minus 119904 gt 0We decompose the integral in two parts as follows
(minusΔ 120573)
minus1205752
119891 (119909) =
1
Γ (1205752)
int
119879
0
1199051205752minus1
119867120573 (119905) 119891 (119909) 119889119905
+
1
Γ (1205752)
int
infin
119879
1199051205752minus1
119867120573 (119905) 119891 (119909) 119889119905
(134)
where 119879 is a constant to be fixed laterWe proceed as in [8] we obtain
10038161003816100381610038161003816119867120573 (119905) 119891 (119909)
10038161003816100381610038161003816le 119862119872120573 (119891) (119909) (135)
On the other hand we use Theorem 29 and the fact that 119891belongs to Bminus120573minus119904
1120573
infininfin(R119889+1
+) to deduce that
10038161003816100381610038161003816119867120573 (119905) 119891 (119909)
10038161003816100381610038161003816le 119862119905
(minus120573minus1199041)210038171003817100381710038171198911003817100381710038171003817Bminus120573minus1199041120573
infininfin (R119889+1+
) (136)
Thus by applying the preceding estimates on the right part of(134) we obtain
1003816100381610038161003816100381610038161003816
(minusΔ 120573)
minus1205752
119891 (119909)
1003816100381610038161003816100381610038161003816
le
1198621
Γ (1205752)
1198791205752119872120573 (119891) (119909)
+
1198622
Γ (1205752)
119879(120575minus120573minus119904
1)210038171003817100381710038171198911003817100381710038171003817Bminus120573minus1199041120573
infininfin (R119889+1+
)
(137)
We fix now
119879 = (
10038171003817100381710038171198911003817100381710038171003817Bminus120573minus1199041120573
infininfin (R119889+1+
)
119872120573 (119891) (119909)
)
2(120573+1199041)
(138)
We obtain
1003816100381610038161003816100381610038161003816
(minusΔ120573)
minus1205752
119891 (119909)
1003816100381610038161003816100381610038161003816
le
1198621 + 1198622
Γ (1205752)
(119872120573(119891)(119909))
12057910038171003817100381710038171198911003817100381710038171003817
1minus120579
Bminus120573minus1199041120573
infininfin (R119889+1+
)
(139)
Thus we deduce that1003817100381710038171003817100381710038171003817
(minusΔ120573)
minus1205752
119891
1003817100381710038171003817100381710038171003817119871119902
120573(R119889+1+
)
le
1198621 + 1198622
Γ (1205752)
10038171003817100381710038171003817119872120573 (119891)
10038171003817100381710038171003817
120579
119871119901
120573(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
1minus120579
Bminus120573minus1199041120573
infininfin (R119889+1+
)
(140)
To conclude we used the fact that the maximal function119872120573
is bounded of 119871119902120573(R119889+1
+) into itself for 119902 gt 1
43 Estimates in Generalized Besov Spaces For any interval 119868ofR (bounded or unbounded) and a normed space 119865(R119889+1
+)
we define the mixed space-time 119871119901(119868 119865(R119889+1
+)) space of
(classes of) measurable functions 119906 119868 rarr 119865(R119889+1
+) such that
||119906||119871119901(119868119865(R119889+1+
)) lt infin with
119906119871119901(119868119865(R119889+1+
)) = (int
119868
119906 (119905 sdot)119901
119865(R119889+1+
)119889119905)
1119901
if 1 le 119901 lt infin
119906119871infin(119868119865(R119889+1+
)) = ess sup119905isin119868
119906 (119905 sdot)119865(R119889+1+
)
(141)
For any interval 119868 of R (bounded or unbounded) anda Banach space 119883 we define the mixed space-time 119862(119868119883)space of continuous functions 119868 rarr 119883 When 119868 is bounded119862(119868119883) is a Banach space with the norm of 119871infin(119868 119883)
Theorem 33 Let 119904 isin R and 1 le 119901 119902 119903 le infin Let 119879 gt 0 119892 isin
B119904120573
119901119903(R119889+1
+) and119891 in 119871119902((0 119879) B
119904minus2+(2119902)120573
119901119903 (R119889+1
+)) Then (76)
has a unique solution
119906 isin 119871119902((0 119879)
B119904+(2119902)120573
119901119903(R
119889+1
+))
⋂119871infin((0 119879)
B119904120573
119901119903(R
119889+1
+))
(142)
and there exists a constant 119862 such that for all 1199021 isin [119902infin] onehas
1199061198711199021 ((0119879)B
119904+(21199021)120573
119901119903(R119889+1+
))
le 119862(10038171003817100381710038171198921003817100381710038171003817B119904120573
119901119903(R119889+1+
)+10038171003817100381710038171198911003817100381710038171003817119871119902((0119879)B
119904minus2+(2119902)120573
119901119903(R119889+1+
)))
(143)
If in addition 119903 lt infin then 119906 isin 119862([0 119879] B119904120573
119901119903(R119889+1
+))
Proof Since 119892 and 119891 are temperate distributions (76) has aunique solution 119906 in S1015840
((0 119879) timesR119889+1
+) which satisfies
F119882 (119906) (119905 120585) = 119890minus1199051205852
F119882 (119892) (120585)
+ int
119905
0
119890(120591minus119905)120585
2
F119882 (119891) (120591 120585) 119889120591
(144)
Next we notice that applying Δ 119895 to (76) and using formula(81) yield
Δ 119895119906 (119905 sdot) = 119867120573 (119905) Δ 119895119892 + int
119905
0
119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot) 119889120591(145)
Therefore
10038171003817100381710038171003817Δ 119895119906 (119905 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le
10038171003817100381710038171003817119867120573(119905)Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+ int
119905
0
10038171003817100381710038171003817119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591
(146)
12 Journal of Function Spaces and Applications
By virtue of Lemma 30 we thus have for some 120581 gt 0
10038171003817100381710038171003817Δ 119895119906(119905 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
le 119862[119890minus1205812211989511990510038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+ int
119905
0
119890minus12058122119895(119905minus120591) 10038171003817
100381710038171003817Δ 119895119891 (120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591]
(147)
Applying convolution inequalities we get
10038171003817100381710038171003817Δ 119895119906
100381710038171003817100381710038171198711199021 ((0119879)119871
119901
120573(R119889+1+
))
le 119862[
[
((
1 minus 119890minus120581119879119902122119895
120581119902122119895
)
11199021
)
10038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+((
1 minus 119890minus120581119879119902222119895
120581119902222119895
)
11199022
)
10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119902((0119879)119871
119901
120573(R119889+1+
))
]
]
(148)
with 11199022 = 1+ 11199021 minus1119902 Finally taking the 119897119903(Z) norm we
conclude that (with the usual convention if 119903 = infin)
1199061198711199021 ((0119879)B
119904+(21199021)120573
119901119903(R119889+1+
))
le 119862[
[
sum
119895isinZ
((
1 minus 119890minus120581119879119902122119895
120581119902122119895
)
1199031199021
)(211989511990410038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
]
]
1119903
+ 119862[
[
sum
119895isinZ
((
1 minus 119890minus120581119879119902222119895
120581119902222119895
)
1199031199022
)
times (2119895(119904minus2+2119902)10038171003817
100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119902(0119879119871
119901
120573(R119889+1+
))
119903
]
]
1119903
(149)
which insures that 119906 isin 119871119902((0 119879)
B119904+(2119902)120573
119901119903 (R119889+1
+))
⋂119871infin((0 119879)
B119904120573
119901119903(R119889+1
+)) and yields the desired inequality
Since 119906 belongs to 119862([0 119879]B119904120573
119901119903(R119889+1
+)) in the case where
119903 is finite may be easily deduced from the density ofSlowast(R
119889+1)⋂
B119904120573
119901119903(R119889+1
+) in B
119904120573
119901119903(R)
Theorem 34 Let 119904 isin R 119879 gt 0 and 1 le 119901 119902 119903 le infinOne supposes that 119892 isin 119861
119904120573
119901119903(R119889+1
+) and 119891 isin 119871
119902((0 119879)
119861119904minus2+(2119902)120573
119901119903 (R119889+1
+)) Then (76) has a unique solution 119906 belong-
ing to
119871119902((0 119879) 119861
119904+(2119902)120573
119901119903(R
119889+1
+))⋂119871
infin((0 119879) 119861
119904120573
119901119903(R
119889+1
+))
(150)
and there exists a constant 119862 such that for all 119902 le 1199021 le infin
1199061198711199021 ((0119879)119861
119904+(21199021)120573
119901119903(R119889+1+
))
le 119862 [ (1 + 11987911199021)10038171003817100381710038171198921003817100381710038171003817119861119904120573
119901119903(R119889+1+
)
+ (1 + 1198791+1119902
1minus1119902
)10038171003817100381710038171198911003817100381710038171003817119871119902((0119879)119861
119904minus2+(2119902)120573
119901119903(R119889+1+
))]
(151)
If in addition 119903 lt infin then 119906 isin 119862([0 119879] 119861119904120573119901119903(R119889+1
+))
Proof Since 119892 119891 are tempered (76) has a unique solution 119906in S1015840
((0 119879) timesR119889+1
+) satisfying
F119882 (119906) (119905 120585) = 119890minus1199051205852
F119882 (119892) (120585)
+ int
119905
0
119890(120591minus119905)120585
2
F119882 (119891) (120591 120585) 119889120591
(152)
Hence applying Δ 119895 119895 ge 0 to (81) we see that
Δ 119895119906 (119905 sdot) = 119867120573 (119905) Δ 119895119892 + int
119905
0
119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot) 119889120591(153)
and thus by Lemma 30 we can deduce that10038171003817100381710038171003817Δ 119895119906 (119905 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
le
10038171003817100381710038171003817119867120573(119905)Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)+ int
119905
0
10038171003817100381710038171003817119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591
le 119862[119890minus1205812211989511990510038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+int
119905
0
119890minus12058122119895(119905minus120591)10038171003817
100381710038171003817Δ 119895119891(120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591]
(154)
Then it follows from convolution inequalities thatΔ 1198951199061198711199021 ((0119879)119871
119901
120573(R119889+1+
))is dominated by
(
1 minus 119890minus120581119879119902122119895
120581119902122119895
)
11199021
10038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119861119904120573
119901119903(R119889+1+
)
+ (
1 minus 119890minus120581119879119902222119895
120581119902222119895
)
11199022
10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119902((0119879)119871
119901
120573(R119889+1+
))
(155)
with 11199022 = 1 + 11199021 minus 1119902 Moreover similarly as above wecan obtain that
1003817100381710038171003817Δminus1119906(119905 sdot)
1003817100381710038171003817119871119901
120573(R119889+1+
)le1003817100381710038171003817Δminus1119892
1003817100381710038171003817119871119901
120573(R119889+1+
)
+ int
119905
0
1003817100381710038171003817Δminus1119891 (120591 sdot)
1003817100381710038171003817119871119901
120573(R119889+1+
)119889120591
(156)
and thus if 1 le 119902 le 1199021 le infin1003817100381710038171003817Δminus1119906
10038171003817100381710038171198711199021 ((0119879)119871
119901
120573(R119889+1+
))
le 119862(119879111990211003817100381710038171003817Δminus1119892
1003817100381710038171003817119871119901
120573(R119889+1+
)+ 119879
111990221003817100381710038171003817Δminus1119891
1003817100381710038171003817119871119902((0119879)119871
119901
120573(R119889+1+
)))
(157)
Journal of Function Spaces and Applications 13
Finally taking the 119897119903-normwith respect to 119895 in (155) and (157)with the usual convention if 119903 = infin we can deduce the desiredestimate
Acknowledgment
Theauthor gratefully acknowledges theDeanship of ScientificResearch at the University of Taibah The author is deeplyindebted to the referee for providing constructive commentsand help in improving the contents of this paper
References
[1] Z Ben Nahia and N Ben Salem ldquoSpherical harmonics andapplications associated with the Weinstein operatorrdquo in Pro-ceedings of the International Conference on PotentialTheory heldin Kouty Czech Republic (ICPT rsquo94) pp 235ndash241 1996
[2] Z Ben Nahia and N Ben Salem ldquoOn a mean value propertyassociated with the Weinstein operatorrdquo in Proceedings of theInternational Conference on Potential Theory held in KoutyCzech Republic (ICPT rsquo94) pp 243ndash253 1996
[3] M Brelot ldquoEquation de Weinstein et potentiels de MarcelRieszrdquo in Seminaire de Theorie de Potentiel Paris No 3 vol 681of Lecture Notes in Mathematics pp 18ndash38 Springer BerlinGermany 1978
[4] H Mejjaoli and M Salhi ldquoUncertainty principles for theweinstein transformrdquo Czechoslovak Mathematical Journal vol61 no 4 pp 941ndash974 2011
[5] H Mejjaoli and A Ould Ahmed Salem ldquoWeinstein Gabortransform and applicationsrdquo Advanced Studies in Pure Mathe-matics vol 2 no 3 pp 203ndash210 2012
[6] H Mejjaoli ldquoBesov spaces associated withthe Weinstein opera-tor and applicationsrdquo In press
[7] T Kawazoe and H Mejjaoli ldquoGeneralized Besov spaces andtheir applicationsrdquo Tokyo Journal of Mathematics vol 35 no 2pp 297ndash320 2012
[8] H Mejjaoli ldquoLittlewood-Paley decomposition associated withthe Dunkl operators and paraproduct operatorsrdquo Journal ofInequalities in Pure and Applied Mathematics vol 9 no 4 pp1ndash25 2008
[9] H Mejjaoli and N Sraeib ldquoGeneralized sobolev spaces inquantum calculus and applicationsrdquo Journal of Inequalities andSpecial Functions vol 1 no 4 pp 43ndash64 2012
[10] H Mejjaoli ldquoGeneralized homogeneous Besov spaces and theirapplicationsrdquo Serdica Mathematical Journal vol 38 no 4 pp575ndash614 2012
[11] H Triebel Interpolation Theory Functions Spaces DifferentialOperators North-Holland AmsterdamThe Netherlands 1978
[12] V S Guliev ldquoOn maximal function and fractional integralassociated with the Bessel differential operatorrdquo MathematicalInequalities and Applications vol 6 no 2 pp 317ndash330 2003
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Volume 2014
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Function Spaces
Abstract and Applied AnalysisHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
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Algebra
Discrete Dynamics in Nature and Society
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
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Decision SciencesAdvances in
Discrete MathematicsJournal of
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Volume 2014 Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Stochastic AnalysisInternational Journal of
Journal of Function Spaces and Applications 9
le 119862119906119903
Bminus2119904120573
119901119903(R119889+1+
)int
infin
0
(sum
119895isinZ
11990511990422119895119904119890minus12058111990522119895
119888119903
119903119895)
119889119905
119905
le 119862119906119903
Bminus2119904120573
119901119903(R119889+1+
)sum
119895isinZ
119888119903
119903119895int
infin
0
(11990511990422119895119904119890minus12058111990522119895
)
119889119905
119905
le 119862Γ (119904) 119906119903
Bminus2119904120573
119901119903(R119889+1+
)
(100)
In order to prove the other inequality let us observe thatfor any 119904 greater than minus1 we have
Δ 119895119906 =
1
Γ (119904 + 1)
int
infin
0
119905119904(minusΔ 120573)
119904+1
119867120573 (119905) Δ 119895119906 119889119905 (101)
Then Lemma 30 Proposition 9 and the fact that the operatorΔ 119895 commutes with the operator119867120573(119905) lead to the following
10038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862int
infin
0
11990511990422119895(119904+1)
119890minus1205811199052211989510038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889119905
(102)
In the case 119903 = infin we simply write
10038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862(sup
119905gt0
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
times int
infin
0
22119895(119904+1)
119890minus12058111990522119895
119889119905
le 11986222119895119904(sup119905gt0
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
(103)
In the case 119903 lt infin Holderrsquos inequality with the weight 119890minus12058111990522119895
gives
(int
infin
0
119905119904119890minus1205811199052211989510038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889119905)
119903
le 1198622minus2119895(119903minus1)
int
infin
0
119905119903119904119890minus1205811199052211989510038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)119889119905
(104)
Thanks to (99) and Fubinirsquos theorem we infer from (102) that
sum
119895isinZ
2minus211989511990311990410038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)le 119862int
infin
0
11990511990311990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)
119889119905
119905
(105)
The theorem is proved
Second Proof ofTheorem 29We only consider the case 1 le 119903 ltinfinThe case 119903 = infin can be shown similarlyWe first prove that
119862minus1119906
Bminus2119904120573
119901119903(R119889+1+
)le
10038171003817100381710038171003817100381710038171003817
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
10038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
(106)
It is easy to see that
Δ 119895119906 = 120594119895lowast119882119864(120573)
2minus2119895lowast119882119906
(107)
where 120594119895 = Fminus1
119882(120593(2
minus119895120585)119890
2minus21198951205852
) and119864(120573)2minus2119895
is the Gauss kernelassociated with Weinstein operators By relation (29) we get
10038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le
10038171003817100381710038171003817120594119895
100381710038171003817100381710038171198711120573(R119889+1+
)
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
) (108)
As10038171003817100381710038171003817120594119895
100381710038171003817100381710038171198711120573(R119889+1+
)= int
R119889+1+
100381610038161003816100381610038161003816F
minus1
119882(120593 (120585) 119890
1205852
)
100381610038161003816100381610038161003816119889120583120573 (120585) lt infin (109)
we obtain10038171003817100381710038171003817Δ 119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
) (110)
Moreover simple calculations give that
119864(120573)
2minus2119895lowast119882119906 = 119867120573 (2
minus4119895minus 119905
2) (119864
(120573)
1199052lowast119882119906)
(111)
Thus from Proposition 26 it follows that100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
100381710038171003817100381710038171003817119864(120573)
1199052lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1
+ )
(112)
for any 119905 isin [2minus119895minus1 2minus119895] which implies that
sum
119895isinZ
2minus211990411989511990310038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)
le 119862 sum
119895isinZ
int
2minus119895
2minus119895minus1(119905
2119904100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903119889119905
119905
le 119862int
infin
0
(1199052119904100381710038171003817100381710038171003817119864(120573)
1199052lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903119889119905
119905
le 119862int
infin
0
(11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903119889119905
119905
(113)
where we have used the fact that 119864(120573)1199052lowast119882119906 = 119867120573(119905
2)119906
We now prove that10038171003817100381710038171003817100381710038171003817
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
10038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
le 119862119906Bminus2119904120573
119901119903(R119889+1+
) (114)
Indeed one has
119864(120573)
2minus2119895lowast119882119906 = sum
119899isinZ
119864(120573)
2minus2119895lowast119882Δ 119899+119895119906 (115)
Arguing as above we have100381710038171003817100381710038171003817119864(120573)
1199052lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)le 119862
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1
+ )
(116)
for any 119905 isin [2minus119895 21minus119895] Thus10038171003817100381710038171003817100381710038171003817
11990511990410038171003817100381710038171003817119867120573 (119905) 119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
10038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
= 2
100381710038171003817100381710038171003817100381710038171003817
1003817100381710038171003817100381710038171199052119904119864(120573)
1199052lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)
100381710038171003817100381710038171003817100381710038171003817119871119903(R+ 119889119905119905)
le 119862 sum
119895isinZ
int
21minus119895
2minus119895(2
minus2119895119904100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903119889119905
119905
le 119862 sum
119895isinZ
(2minus2119895119904
sum
119899isinZ
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
(117)
10 Journal of Function Spaces and Applications
On the other hand it is easy to see that100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)le 1198622
minus211989911990410038171003817100381710038171003817Δ 119899+119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
) (118)
for any 119904 gt 0 For 0 lt 1199041 lt 119904 lt 1199042 and by using theMinkowskiinequality we have
sum
119895isinZ
(2minus2119895119904
sum
119899isinZ
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
le sum
119895isinZ
(2minus2119895119904
0
sum
minusinfin
2minus21198991199041
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
+ sum
119895isinZ
(2minus2119895119904
sum
119899isinN
2minus21198991199042
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
le 119862(
0
sum
minusinfin
2minus2119899(119904
1minus119904)(sum
119895isinZ
(2minus2(119899+119895)11990311990410038171003817
100381710038171003817Δ 119899+119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
)
1119903
)
119903
+ 119862(sum
N
2minus2119899(119904
2minus119904)(sum
119895isinZ
(2minus2(119899+119895)11990311990410038171003817
100381710038171003817Δ 119899+119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
)
1119903
)
119903
le 119862 sum
119895isinZ
2minus211989511990311990410038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)
(119)
The result is immediately from (117) and (119)
42 Embedding Sobolev Theorems
Theorem 31 Let 1 lt 119901 lt infin and let 0 lt 119904 lt (119889 + 2120573 +
2)119901There exists a positive constant119862 such that for all function119891 isin
H119904
119901120573(R119889+1
+) one has
10038171003817100381710038171198911003817100381710038171003817119871119902
120573(R119889+1+
)le 119862
10038171003817100381710038171198911003817100381710038171003817
1minus120579
H119904119901120573(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
120579
B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
) (120)
where 120579 = 119904119901(119889+2120573+2) and 119902 = 119901(119889+2120573+2)(119889+2120573+2minus119901119904)
Proof Bydensity we can suppose that119891belongs toSlowast(R119889+1
)It is easy to see that
119891 = int
infin
0
119867120573 (119905) Δ 120573119891119889119905(121)
and decompose the integral in two parts as follows
119891 = int
119860
0
119867120573 (119905) Δ 120573119891119889119905 + int
infin
119860
119867120573 (119905) Δ 120573119891119889119905(122)
where 119860 is a constant to be fixed laterOn the other hand byTheorem 29 we obtain10038171003817100381710038171003817119867120573 (119905) Δ 120573119891
10038171003817100381710038171003817119871infin120573(R119889+1+
)
le
119862
1199051minus(12)(119904minus(119889+2120573+2)119901)
10038171003817100381710038171198911003817100381710038171003817B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
)
(123)
Therefore after integrating we get
int
infin
119860
10038171003817100381710038171003817119867120573 (119905) Δ 120573119891
10038171003817100381710038171003817119871infin120573(R119889+1+
)119889119905
le 119860(12)(119904minus(119889+2120573+2)119901)1003817
1003817100381710038171198911003817100381710038171003817B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
)
(124)
On the other hand denoting 119892 = (minusΔ 120573)1199042119891 we have
119867120573 (119905) Δ 120573119891 =
1
(minus119905)1minus1199042
119867120573 (119905) (minus119905Δ 120573)
1minus1199042
119892 (125)
We proceed as in [8] we prove that1003816100381610038161003816100381610038161003816
119867120573 (119905) (minus119905Δ 120573)
1minus1199042
119892 (119909)
1003816100381610038161003816100381610038161003816
le 119862 (119904)119872120573 (119892) (119909) (126)
where119872120573(119892) is a maximal function of 119892 associated with theWeinstein operators (cf [12])
This leads to100381610038161003816100381610038161003816100381610038161003816
int
119860
0
119867120573 (119905) Δ 120573119891 (119909) 119889119905
100381610038161003816100381610038161003816100381610038161003816
le 1198621198601199042119872120573 (119892) (119909) (127)
In conclusion we get10038161003816100381610038161003816100381610038161003816
int
infin
0
119867120573 (119905) Δ 120573119891 (119909) 119889119905
10038161003816100381610038161003816100381610038161003816
le 119862 (1198601199042119872120573 (119892) (119909)
+119860(12)(119904minus(119889+2120573+2)119901)1003817
1003817100381710038171198911003817100381710038171003817B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
))
(128)
and the choice of 119860 such that
119860(119889+2120573+2)2119901
119872120573 (119892) (119909) =10038171003817100381710038171198911003817100381710038171003817B119904minus(119889+2120573+2)119901120573
infininfin (R119889+1+
)(129)
ensures that10038161003816100381610038161003816100381610038161003816
int
infin
0
119867120573 (119905) Δ 120573119891 (119909) 119889119905
10038161003816100381610038161003816100381610038161003816
le 119862(119872120573(119892)(119909))
1minus(119901119904(119889+2120573+2))10038171003817100381710038171198911003817100381710038171003817
119901119904(119889+2120573+2)
B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
)
(130)
Finally taking the 119871119902120573norm with 119902 = 119901(119889 + 2120573 + 2)(119889 + 2120573 +
2minus119901119904) ends the proof thanks to the fact themaximal function119872120573 is bounded of 119871119902
120573(R119889+1
+) into itself for 119902 gt 1
Theorem 32 Let 1 lt 119901 lt 119902 lt infin For all function 119891 such that119891 isin
H1199041
119901120573(R119889+1
+)⋂
Bminus120573120573
infininfin(R119889+1
+) one has
10038171003817100381710038171198911003817100381710038171003817H119904119901120573(R119889+1+
)le 119862
10038171003817100381710038171198911003817100381710038171003817
120579
H1199041
119901120573(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
1minus120579
Bminus120573120573
infininfin(R119889+1
+) (131)
where 120579 = 119901119902 119904 = 1205791199041 minus (1 minus 120579)120573 with 120573 gt 0 minus120573 lt 119904 lt 1199041
Proof It suffices to prove that1003817100381710038171003817100381710038171003817
(minusΔ 120573)
(119904minus1199041)2
119891
1003817100381710038171003817100381710038171003817119871119902
120573(R119889+1+
)
le 11986210038171003817100381710038171198911003817100381710038171003817
120579
119871119901
120573(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
1minus120579
Bminus120573minus1199041120573
infininfin (R119889+1+
)
(132)
Journal of Function Spaces and Applications 11
Indeed we use the following identity (which may be easilyproven by taking the Weinstein transform in 119909 of both sides)
(minusΔ 120573)
minus1205752
119891 (119909) =
1
Γ (1205752)
int
infin
0
1199051205752minus1
119867120573 (119905) 119891 (119909) 119889119905 (133)
with 120575 = 1199041 minus 119904 gt 0We decompose the integral in two parts as follows
(minusΔ 120573)
minus1205752
119891 (119909) =
1
Γ (1205752)
int
119879
0
1199051205752minus1
119867120573 (119905) 119891 (119909) 119889119905
+
1
Γ (1205752)
int
infin
119879
1199051205752minus1
119867120573 (119905) 119891 (119909) 119889119905
(134)
where 119879 is a constant to be fixed laterWe proceed as in [8] we obtain
10038161003816100381610038161003816119867120573 (119905) 119891 (119909)
10038161003816100381610038161003816le 119862119872120573 (119891) (119909) (135)
On the other hand we use Theorem 29 and the fact that 119891belongs to Bminus120573minus119904
1120573
infininfin(R119889+1
+) to deduce that
10038161003816100381610038161003816119867120573 (119905) 119891 (119909)
10038161003816100381610038161003816le 119862119905
(minus120573minus1199041)210038171003817100381710038171198911003817100381710038171003817Bminus120573minus1199041120573
infininfin (R119889+1+
) (136)
Thus by applying the preceding estimates on the right part of(134) we obtain
1003816100381610038161003816100381610038161003816
(minusΔ 120573)
minus1205752
119891 (119909)
1003816100381610038161003816100381610038161003816
le
1198621
Γ (1205752)
1198791205752119872120573 (119891) (119909)
+
1198622
Γ (1205752)
119879(120575minus120573minus119904
1)210038171003817100381710038171198911003817100381710038171003817Bminus120573minus1199041120573
infininfin (R119889+1+
)
(137)
We fix now
119879 = (
10038171003817100381710038171198911003817100381710038171003817Bminus120573minus1199041120573
infininfin (R119889+1+
)
119872120573 (119891) (119909)
)
2(120573+1199041)
(138)
We obtain
1003816100381610038161003816100381610038161003816
(minusΔ120573)
minus1205752
119891 (119909)
1003816100381610038161003816100381610038161003816
le
1198621 + 1198622
Γ (1205752)
(119872120573(119891)(119909))
12057910038171003817100381710038171198911003817100381710038171003817
1minus120579
Bminus120573minus1199041120573
infininfin (R119889+1+
)
(139)
Thus we deduce that1003817100381710038171003817100381710038171003817
(minusΔ120573)
minus1205752
119891
1003817100381710038171003817100381710038171003817119871119902
120573(R119889+1+
)
le
1198621 + 1198622
Γ (1205752)
10038171003817100381710038171003817119872120573 (119891)
10038171003817100381710038171003817
120579
119871119901
120573(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
1minus120579
Bminus120573minus1199041120573
infininfin (R119889+1+
)
(140)
To conclude we used the fact that the maximal function119872120573
is bounded of 119871119902120573(R119889+1
+) into itself for 119902 gt 1
43 Estimates in Generalized Besov Spaces For any interval 119868ofR (bounded or unbounded) and a normed space 119865(R119889+1
+)
we define the mixed space-time 119871119901(119868 119865(R119889+1
+)) space of
(classes of) measurable functions 119906 119868 rarr 119865(R119889+1
+) such that
||119906||119871119901(119868119865(R119889+1+
)) lt infin with
119906119871119901(119868119865(R119889+1+
)) = (int
119868
119906 (119905 sdot)119901
119865(R119889+1+
)119889119905)
1119901
if 1 le 119901 lt infin
119906119871infin(119868119865(R119889+1+
)) = ess sup119905isin119868
119906 (119905 sdot)119865(R119889+1+
)
(141)
For any interval 119868 of R (bounded or unbounded) anda Banach space 119883 we define the mixed space-time 119862(119868119883)space of continuous functions 119868 rarr 119883 When 119868 is bounded119862(119868119883) is a Banach space with the norm of 119871infin(119868 119883)
Theorem 33 Let 119904 isin R and 1 le 119901 119902 119903 le infin Let 119879 gt 0 119892 isin
B119904120573
119901119903(R119889+1
+) and119891 in 119871119902((0 119879) B
119904minus2+(2119902)120573
119901119903 (R119889+1
+)) Then (76)
has a unique solution
119906 isin 119871119902((0 119879)
B119904+(2119902)120573
119901119903(R
119889+1
+))
⋂119871infin((0 119879)
B119904120573
119901119903(R
119889+1
+))
(142)
and there exists a constant 119862 such that for all 1199021 isin [119902infin] onehas
1199061198711199021 ((0119879)B
119904+(21199021)120573
119901119903(R119889+1+
))
le 119862(10038171003817100381710038171198921003817100381710038171003817B119904120573
119901119903(R119889+1+
)+10038171003817100381710038171198911003817100381710038171003817119871119902((0119879)B
119904minus2+(2119902)120573
119901119903(R119889+1+
)))
(143)
If in addition 119903 lt infin then 119906 isin 119862([0 119879] B119904120573
119901119903(R119889+1
+))
Proof Since 119892 and 119891 are temperate distributions (76) has aunique solution 119906 in S1015840
((0 119879) timesR119889+1
+) which satisfies
F119882 (119906) (119905 120585) = 119890minus1199051205852
F119882 (119892) (120585)
+ int
119905
0
119890(120591minus119905)120585
2
F119882 (119891) (120591 120585) 119889120591
(144)
Next we notice that applying Δ 119895 to (76) and using formula(81) yield
Δ 119895119906 (119905 sdot) = 119867120573 (119905) Δ 119895119892 + int
119905
0
119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot) 119889120591(145)
Therefore
10038171003817100381710038171003817Δ 119895119906 (119905 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le
10038171003817100381710038171003817119867120573(119905)Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+ int
119905
0
10038171003817100381710038171003817119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591
(146)
12 Journal of Function Spaces and Applications
By virtue of Lemma 30 we thus have for some 120581 gt 0
10038171003817100381710038171003817Δ 119895119906(119905 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
le 119862[119890minus1205812211989511990510038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+ int
119905
0
119890minus12058122119895(119905minus120591) 10038171003817
100381710038171003817Δ 119895119891 (120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591]
(147)
Applying convolution inequalities we get
10038171003817100381710038171003817Δ 119895119906
100381710038171003817100381710038171198711199021 ((0119879)119871
119901
120573(R119889+1+
))
le 119862[
[
((
1 minus 119890minus120581119879119902122119895
120581119902122119895
)
11199021
)
10038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+((
1 minus 119890minus120581119879119902222119895
120581119902222119895
)
11199022
)
10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119902((0119879)119871
119901
120573(R119889+1+
))
]
]
(148)
with 11199022 = 1+ 11199021 minus1119902 Finally taking the 119897119903(Z) norm we
conclude that (with the usual convention if 119903 = infin)
1199061198711199021 ((0119879)B
119904+(21199021)120573
119901119903(R119889+1+
))
le 119862[
[
sum
119895isinZ
((
1 minus 119890minus120581119879119902122119895
120581119902122119895
)
1199031199021
)(211989511990410038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
]
]
1119903
+ 119862[
[
sum
119895isinZ
((
1 minus 119890minus120581119879119902222119895
120581119902222119895
)
1199031199022
)
times (2119895(119904minus2+2119902)10038171003817
100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119902(0119879119871
119901
120573(R119889+1+
))
119903
]
]
1119903
(149)
which insures that 119906 isin 119871119902((0 119879)
B119904+(2119902)120573
119901119903 (R119889+1
+))
⋂119871infin((0 119879)
B119904120573
119901119903(R119889+1
+)) and yields the desired inequality
Since 119906 belongs to 119862([0 119879]B119904120573
119901119903(R119889+1
+)) in the case where
119903 is finite may be easily deduced from the density ofSlowast(R
119889+1)⋂
B119904120573
119901119903(R119889+1
+) in B
119904120573
119901119903(R)
Theorem 34 Let 119904 isin R 119879 gt 0 and 1 le 119901 119902 119903 le infinOne supposes that 119892 isin 119861
119904120573
119901119903(R119889+1
+) and 119891 isin 119871
119902((0 119879)
119861119904minus2+(2119902)120573
119901119903 (R119889+1
+)) Then (76) has a unique solution 119906 belong-
ing to
119871119902((0 119879) 119861
119904+(2119902)120573
119901119903(R
119889+1
+))⋂119871
infin((0 119879) 119861
119904120573
119901119903(R
119889+1
+))
(150)
and there exists a constant 119862 such that for all 119902 le 1199021 le infin
1199061198711199021 ((0119879)119861
119904+(21199021)120573
119901119903(R119889+1+
))
le 119862 [ (1 + 11987911199021)10038171003817100381710038171198921003817100381710038171003817119861119904120573
119901119903(R119889+1+
)
+ (1 + 1198791+1119902
1minus1119902
)10038171003817100381710038171198911003817100381710038171003817119871119902((0119879)119861
119904minus2+(2119902)120573
119901119903(R119889+1+
))]
(151)
If in addition 119903 lt infin then 119906 isin 119862([0 119879] 119861119904120573119901119903(R119889+1
+))
Proof Since 119892 119891 are tempered (76) has a unique solution 119906in S1015840
((0 119879) timesR119889+1
+) satisfying
F119882 (119906) (119905 120585) = 119890minus1199051205852
F119882 (119892) (120585)
+ int
119905
0
119890(120591minus119905)120585
2
F119882 (119891) (120591 120585) 119889120591
(152)
Hence applying Δ 119895 119895 ge 0 to (81) we see that
Δ 119895119906 (119905 sdot) = 119867120573 (119905) Δ 119895119892 + int
119905
0
119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot) 119889120591(153)
and thus by Lemma 30 we can deduce that10038171003817100381710038171003817Δ 119895119906 (119905 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
le
10038171003817100381710038171003817119867120573(119905)Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)+ int
119905
0
10038171003817100381710038171003817119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591
le 119862[119890minus1205812211989511990510038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+int
119905
0
119890minus12058122119895(119905minus120591)10038171003817
100381710038171003817Δ 119895119891(120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591]
(154)
Then it follows from convolution inequalities thatΔ 1198951199061198711199021 ((0119879)119871
119901
120573(R119889+1+
))is dominated by
(
1 minus 119890minus120581119879119902122119895
120581119902122119895
)
11199021
10038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119861119904120573
119901119903(R119889+1+
)
+ (
1 minus 119890minus120581119879119902222119895
120581119902222119895
)
11199022
10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119902((0119879)119871
119901
120573(R119889+1+
))
(155)
with 11199022 = 1 + 11199021 minus 1119902 Moreover similarly as above wecan obtain that
1003817100381710038171003817Δminus1119906(119905 sdot)
1003817100381710038171003817119871119901
120573(R119889+1+
)le1003817100381710038171003817Δminus1119892
1003817100381710038171003817119871119901
120573(R119889+1+
)
+ int
119905
0
1003817100381710038171003817Δminus1119891 (120591 sdot)
1003817100381710038171003817119871119901
120573(R119889+1+
)119889120591
(156)
and thus if 1 le 119902 le 1199021 le infin1003817100381710038171003817Δminus1119906
10038171003817100381710038171198711199021 ((0119879)119871
119901
120573(R119889+1+
))
le 119862(119879111990211003817100381710038171003817Δminus1119892
1003817100381710038171003817119871119901
120573(R119889+1+
)+ 119879
111990221003817100381710038171003817Δminus1119891
1003817100381710038171003817119871119902((0119879)119871
119901
120573(R119889+1+
)))
(157)
Journal of Function Spaces and Applications 13
Finally taking the 119897119903-normwith respect to 119895 in (155) and (157)with the usual convention if 119903 = infin we can deduce the desiredestimate
Acknowledgment
Theauthor gratefully acknowledges theDeanship of ScientificResearch at the University of Taibah The author is deeplyindebted to the referee for providing constructive commentsand help in improving the contents of this paper
References
[1] Z Ben Nahia and N Ben Salem ldquoSpherical harmonics andapplications associated with the Weinstein operatorrdquo in Pro-ceedings of the International Conference on PotentialTheory heldin Kouty Czech Republic (ICPT rsquo94) pp 235ndash241 1996
[2] Z Ben Nahia and N Ben Salem ldquoOn a mean value propertyassociated with the Weinstein operatorrdquo in Proceedings of theInternational Conference on Potential Theory held in KoutyCzech Republic (ICPT rsquo94) pp 243ndash253 1996
[3] M Brelot ldquoEquation de Weinstein et potentiels de MarcelRieszrdquo in Seminaire de Theorie de Potentiel Paris No 3 vol 681of Lecture Notes in Mathematics pp 18ndash38 Springer BerlinGermany 1978
[4] H Mejjaoli and M Salhi ldquoUncertainty principles for theweinstein transformrdquo Czechoslovak Mathematical Journal vol61 no 4 pp 941ndash974 2011
[5] H Mejjaoli and A Ould Ahmed Salem ldquoWeinstein Gabortransform and applicationsrdquo Advanced Studies in Pure Mathe-matics vol 2 no 3 pp 203ndash210 2012
[6] H Mejjaoli ldquoBesov spaces associated withthe Weinstein opera-tor and applicationsrdquo In press
[7] T Kawazoe and H Mejjaoli ldquoGeneralized Besov spaces andtheir applicationsrdquo Tokyo Journal of Mathematics vol 35 no 2pp 297ndash320 2012
[8] H Mejjaoli ldquoLittlewood-Paley decomposition associated withthe Dunkl operators and paraproduct operatorsrdquo Journal ofInequalities in Pure and Applied Mathematics vol 9 no 4 pp1ndash25 2008
[9] H Mejjaoli and N Sraeib ldquoGeneralized sobolev spaces inquantum calculus and applicationsrdquo Journal of Inequalities andSpecial Functions vol 1 no 4 pp 43ndash64 2012
[10] H Mejjaoli ldquoGeneralized homogeneous Besov spaces and theirapplicationsrdquo Serdica Mathematical Journal vol 38 no 4 pp575ndash614 2012
[11] H Triebel Interpolation Theory Functions Spaces DifferentialOperators North-Holland AmsterdamThe Netherlands 1978
[12] V S Guliev ldquoOn maximal function and fractional integralassociated with the Bessel differential operatorrdquo MathematicalInequalities and Applications vol 6 no 2 pp 317ndash330 2003
Submit your manuscripts athttpwwwhindawicom
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
MathematicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Mathematical Problems in Engineering
Hindawi Publishing Corporationhttpwwwhindawicom
Differential EquationsInternational Journal of
Volume 2014
Applied MathematicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Probability and StatisticsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Mathematical PhysicsAdvances in
Complex AnalysisJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
OptimizationJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
CombinatoricsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
International Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Operations ResearchAdvances in
Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Function Spaces
Abstract and Applied AnalysisHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
International Journal of Mathematics and Mathematical Sciences
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Algebra
Discrete Dynamics in Nature and Society
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Decision SciencesAdvances in
Discrete MathematicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom
Volume 2014 Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Stochastic AnalysisInternational Journal of
10 Journal of Function Spaces and Applications
On the other hand it is easy to see that100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
)le 1198622
minus211989911990410038171003817100381710038171003817Δ 119899+119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
) (118)
for any 119904 gt 0 For 0 lt 1199041 lt 119904 lt 1199042 and by using theMinkowskiinequality we have
sum
119895isinZ
(2minus2119895119904
sum
119899isinZ
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
le sum
119895isinZ
(2minus2119895119904
0
sum
minusinfin
2minus21198991199041
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
+ sum
119895isinZ
(2minus2119895119904
sum
119899isinN
2minus21198991199042
100381710038171003817100381710038171003817119864(120573)
2minus2119895lowast119882Δ 119899+119895119906
100381710038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
le 119862(
0
sum
minusinfin
2minus2119899(119904
1minus119904)(sum
119895isinZ
(2minus2(119899+119895)11990311990410038171003817
100381710038171003817Δ 119899+119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
)
1119903
)
119903
+ 119862(sum
N
2minus2119899(119904
2minus119904)(sum
119895isinZ
(2minus2(119899+119895)11990311990410038171003817
100381710038171003817Δ 119899+119895119906
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
)
1119903
)
119903
le 119862 sum
119895isinZ
2minus211989511990311990410038171003817
100381710038171003817Δ 119895119906
10038171003817100381710038171003817
119903
119871119901
120573(R119889+1+
)
(119)
The result is immediately from (117) and (119)
42 Embedding Sobolev Theorems
Theorem 31 Let 1 lt 119901 lt infin and let 0 lt 119904 lt (119889 + 2120573 +
2)119901There exists a positive constant119862 such that for all function119891 isin
H119904
119901120573(R119889+1
+) one has
10038171003817100381710038171198911003817100381710038171003817119871119902
120573(R119889+1+
)le 119862
10038171003817100381710038171198911003817100381710038171003817
1minus120579
H119904119901120573(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
120579
B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
) (120)
where 120579 = 119904119901(119889+2120573+2) and 119902 = 119901(119889+2120573+2)(119889+2120573+2minus119901119904)
Proof Bydensity we can suppose that119891belongs toSlowast(R119889+1
)It is easy to see that
119891 = int
infin
0
119867120573 (119905) Δ 120573119891119889119905(121)
and decompose the integral in two parts as follows
119891 = int
119860
0
119867120573 (119905) Δ 120573119891119889119905 + int
infin
119860
119867120573 (119905) Δ 120573119891119889119905(122)
where 119860 is a constant to be fixed laterOn the other hand byTheorem 29 we obtain10038171003817100381710038171003817119867120573 (119905) Δ 120573119891
10038171003817100381710038171003817119871infin120573(R119889+1+
)
le
119862
1199051minus(12)(119904minus(119889+2120573+2)119901)
10038171003817100381710038171198911003817100381710038171003817B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
)
(123)
Therefore after integrating we get
int
infin
119860
10038171003817100381710038171003817119867120573 (119905) Δ 120573119891
10038171003817100381710038171003817119871infin120573(R119889+1+
)119889119905
le 119860(12)(119904minus(119889+2120573+2)119901)1003817
1003817100381710038171198911003817100381710038171003817B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
)
(124)
On the other hand denoting 119892 = (minusΔ 120573)1199042119891 we have
119867120573 (119905) Δ 120573119891 =
1
(minus119905)1minus1199042
119867120573 (119905) (minus119905Δ 120573)
1minus1199042
119892 (125)
We proceed as in [8] we prove that1003816100381610038161003816100381610038161003816
119867120573 (119905) (minus119905Δ 120573)
1minus1199042
119892 (119909)
1003816100381610038161003816100381610038161003816
le 119862 (119904)119872120573 (119892) (119909) (126)
where119872120573(119892) is a maximal function of 119892 associated with theWeinstein operators (cf [12])
This leads to100381610038161003816100381610038161003816100381610038161003816
int
119860
0
119867120573 (119905) Δ 120573119891 (119909) 119889119905
100381610038161003816100381610038161003816100381610038161003816
le 1198621198601199042119872120573 (119892) (119909) (127)
In conclusion we get10038161003816100381610038161003816100381610038161003816
int
infin
0
119867120573 (119905) Δ 120573119891 (119909) 119889119905
10038161003816100381610038161003816100381610038161003816
le 119862 (1198601199042119872120573 (119892) (119909)
+119860(12)(119904minus(119889+2120573+2)119901)1003817
1003817100381710038171198911003817100381710038171003817B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
))
(128)
and the choice of 119860 such that
119860(119889+2120573+2)2119901
119872120573 (119892) (119909) =10038171003817100381710038171198911003817100381710038171003817B119904minus(119889+2120573+2)119901120573
infininfin (R119889+1+
)(129)
ensures that10038161003816100381610038161003816100381610038161003816
int
infin
0
119867120573 (119905) Δ 120573119891 (119909) 119889119905
10038161003816100381610038161003816100381610038161003816
le 119862(119872120573(119892)(119909))
1minus(119901119904(119889+2120573+2))10038171003817100381710038171198911003817100381710038171003817
119901119904(119889+2120573+2)
B119904minus((119889+2120573+2)119901)120573
infininfin (R119889+1+
)
(130)
Finally taking the 119871119902120573norm with 119902 = 119901(119889 + 2120573 + 2)(119889 + 2120573 +
2minus119901119904) ends the proof thanks to the fact themaximal function119872120573 is bounded of 119871119902
120573(R119889+1
+) into itself for 119902 gt 1
Theorem 32 Let 1 lt 119901 lt 119902 lt infin For all function 119891 such that119891 isin
H1199041
119901120573(R119889+1
+)⋂
Bminus120573120573
infininfin(R119889+1
+) one has
10038171003817100381710038171198911003817100381710038171003817H119904119901120573(R119889+1+
)le 119862
10038171003817100381710038171198911003817100381710038171003817
120579
H1199041
119901120573(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
1minus120579
Bminus120573120573
infininfin(R119889+1
+) (131)
where 120579 = 119901119902 119904 = 1205791199041 minus (1 minus 120579)120573 with 120573 gt 0 minus120573 lt 119904 lt 1199041
Proof It suffices to prove that1003817100381710038171003817100381710038171003817
(minusΔ 120573)
(119904minus1199041)2
119891
1003817100381710038171003817100381710038171003817119871119902
120573(R119889+1+
)
le 11986210038171003817100381710038171198911003817100381710038171003817
120579
119871119901
120573(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
1minus120579
Bminus120573minus1199041120573
infininfin (R119889+1+
)
(132)
Journal of Function Spaces and Applications 11
Indeed we use the following identity (which may be easilyproven by taking the Weinstein transform in 119909 of both sides)
(minusΔ 120573)
minus1205752
119891 (119909) =
1
Γ (1205752)
int
infin
0
1199051205752minus1
119867120573 (119905) 119891 (119909) 119889119905 (133)
with 120575 = 1199041 minus 119904 gt 0We decompose the integral in two parts as follows
(minusΔ 120573)
minus1205752
119891 (119909) =
1
Γ (1205752)
int
119879
0
1199051205752minus1
119867120573 (119905) 119891 (119909) 119889119905
+
1
Γ (1205752)
int
infin
119879
1199051205752minus1
119867120573 (119905) 119891 (119909) 119889119905
(134)
where 119879 is a constant to be fixed laterWe proceed as in [8] we obtain
10038161003816100381610038161003816119867120573 (119905) 119891 (119909)
10038161003816100381610038161003816le 119862119872120573 (119891) (119909) (135)
On the other hand we use Theorem 29 and the fact that 119891belongs to Bminus120573minus119904
1120573
infininfin(R119889+1
+) to deduce that
10038161003816100381610038161003816119867120573 (119905) 119891 (119909)
10038161003816100381610038161003816le 119862119905
(minus120573minus1199041)210038171003817100381710038171198911003817100381710038171003817Bminus120573minus1199041120573
infininfin (R119889+1+
) (136)
Thus by applying the preceding estimates on the right part of(134) we obtain
1003816100381610038161003816100381610038161003816
(minusΔ 120573)
minus1205752
119891 (119909)
1003816100381610038161003816100381610038161003816
le
1198621
Γ (1205752)
1198791205752119872120573 (119891) (119909)
+
1198622
Γ (1205752)
119879(120575minus120573minus119904
1)210038171003817100381710038171198911003817100381710038171003817Bminus120573minus1199041120573
infininfin (R119889+1+
)
(137)
We fix now
119879 = (
10038171003817100381710038171198911003817100381710038171003817Bminus120573minus1199041120573
infininfin (R119889+1+
)
119872120573 (119891) (119909)
)
2(120573+1199041)
(138)
We obtain
1003816100381610038161003816100381610038161003816
(minusΔ120573)
minus1205752
119891 (119909)
1003816100381610038161003816100381610038161003816
le
1198621 + 1198622
Γ (1205752)
(119872120573(119891)(119909))
12057910038171003817100381710038171198911003817100381710038171003817
1minus120579
Bminus120573minus1199041120573
infininfin (R119889+1+
)
(139)
Thus we deduce that1003817100381710038171003817100381710038171003817
(minusΔ120573)
minus1205752
119891
1003817100381710038171003817100381710038171003817119871119902
120573(R119889+1+
)
le
1198621 + 1198622
Γ (1205752)
10038171003817100381710038171003817119872120573 (119891)
10038171003817100381710038171003817
120579
119871119901
120573(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
1minus120579
Bminus120573minus1199041120573
infininfin (R119889+1+
)
(140)
To conclude we used the fact that the maximal function119872120573
is bounded of 119871119902120573(R119889+1
+) into itself for 119902 gt 1
43 Estimates in Generalized Besov Spaces For any interval 119868ofR (bounded or unbounded) and a normed space 119865(R119889+1
+)
we define the mixed space-time 119871119901(119868 119865(R119889+1
+)) space of
(classes of) measurable functions 119906 119868 rarr 119865(R119889+1
+) such that
||119906||119871119901(119868119865(R119889+1+
)) lt infin with
119906119871119901(119868119865(R119889+1+
)) = (int
119868
119906 (119905 sdot)119901
119865(R119889+1+
)119889119905)
1119901
if 1 le 119901 lt infin
119906119871infin(119868119865(R119889+1+
)) = ess sup119905isin119868
119906 (119905 sdot)119865(R119889+1+
)
(141)
For any interval 119868 of R (bounded or unbounded) anda Banach space 119883 we define the mixed space-time 119862(119868119883)space of continuous functions 119868 rarr 119883 When 119868 is bounded119862(119868119883) is a Banach space with the norm of 119871infin(119868 119883)
Theorem 33 Let 119904 isin R and 1 le 119901 119902 119903 le infin Let 119879 gt 0 119892 isin
B119904120573
119901119903(R119889+1
+) and119891 in 119871119902((0 119879) B
119904minus2+(2119902)120573
119901119903 (R119889+1
+)) Then (76)
has a unique solution
119906 isin 119871119902((0 119879)
B119904+(2119902)120573
119901119903(R
119889+1
+))
⋂119871infin((0 119879)
B119904120573
119901119903(R
119889+1
+))
(142)
and there exists a constant 119862 such that for all 1199021 isin [119902infin] onehas
1199061198711199021 ((0119879)B
119904+(21199021)120573
119901119903(R119889+1+
))
le 119862(10038171003817100381710038171198921003817100381710038171003817B119904120573
119901119903(R119889+1+
)+10038171003817100381710038171198911003817100381710038171003817119871119902((0119879)B
119904minus2+(2119902)120573
119901119903(R119889+1+
)))
(143)
If in addition 119903 lt infin then 119906 isin 119862([0 119879] B119904120573
119901119903(R119889+1
+))
Proof Since 119892 and 119891 are temperate distributions (76) has aunique solution 119906 in S1015840
((0 119879) timesR119889+1
+) which satisfies
F119882 (119906) (119905 120585) = 119890minus1199051205852
F119882 (119892) (120585)
+ int
119905
0
119890(120591minus119905)120585
2
F119882 (119891) (120591 120585) 119889120591
(144)
Next we notice that applying Δ 119895 to (76) and using formula(81) yield
Δ 119895119906 (119905 sdot) = 119867120573 (119905) Δ 119895119892 + int
119905
0
119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot) 119889120591(145)
Therefore
10038171003817100381710038171003817Δ 119895119906 (119905 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le
10038171003817100381710038171003817119867120573(119905)Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+ int
119905
0
10038171003817100381710038171003817119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591
(146)
12 Journal of Function Spaces and Applications
By virtue of Lemma 30 we thus have for some 120581 gt 0
10038171003817100381710038171003817Δ 119895119906(119905 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
le 119862[119890minus1205812211989511990510038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+ int
119905
0
119890minus12058122119895(119905minus120591) 10038171003817
100381710038171003817Δ 119895119891 (120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591]
(147)
Applying convolution inequalities we get
10038171003817100381710038171003817Δ 119895119906
100381710038171003817100381710038171198711199021 ((0119879)119871
119901
120573(R119889+1+
))
le 119862[
[
((
1 minus 119890minus120581119879119902122119895
120581119902122119895
)
11199021
)
10038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+((
1 minus 119890minus120581119879119902222119895
120581119902222119895
)
11199022
)
10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119902((0119879)119871
119901
120573(R119889+1+
))
]
]
(148)
with 11199022 = 1+ 11199021 minus1119902 Finally taking the 119897119903(Z) norm we
conclude that (with the usual convention if 119903 = infin)
1199061198711199021 ((0119879)B
119904+(21199021)120573
119901119903(R119889+1+
))
le 119862[
[
sum
119895isinZ
((
1 minus 119890minus120581119879119902122119895
120581119902122119895
)
1199031199021
)(211989511990410038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
]
]
1119903
+ 119862[
[
sum
119895isinZ
((
1 minus 119890minus120581119879119902222119895
120581119902222119895
)
1199031199022
)
times (2119895(119904minus2+2119902)10038171003817
100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119902(0119879119871
119901
120573(R119889+1+
))
119903
]
]
1119903
(149)
which insures that 119906 isin 119871119902((0 119879)
B119904+(2119902)120573
119901119903 (R119889+1
+))
⋂119871infin((0 119879)
B119904120573
119901119903(R119889+1
+)) and yields the desired inequality
Since 119906 belongs to 119862([0 119879]B119904120573
119901119903(R119889+1
+)) in the case where
119903 is finite may be easily deduced from the density ofSlowast(R
119889+1)⋂
B119904120573
119901119903(R119889+1
+) in B
119904120573
119901119903(R)
Theorem 34 Let 119904 isin R 119879 gt 0 and 1 le 119901 119902 119903 le infinOne supposes that 119892 isin 119861
119904120573
119901119903(R119889+1
+) and 119891 isin 119871
119902((0 119879)
119861119904minus2+(2119902)120573
119901119903 (R119889+1
+)) Then (76) has a unique solution 119906 belong-
ing to
119871119902((0 119879) 119861
119904+(2119902)120573
119901119903(R
119889+1
+))⋂119871
infin((0 119879) 119861
119904120573
119901119903(R
119889+1
+))
(150)
and there exists a constant 119862 such that for all 119902 le 1199021 le infin
1199061198711199021 ((0119879)119861
119904+(21199021)120573
119901119903(R119889+1+
))
le 119862 [ (1 + 11987911199021)10038171003817100381710038171198921003817100381710038171003817119861119904120573
119901119903(R119889+1+
)
+ (1 + 1198791+1119902
1minus1119902
)10038171003817100381710038171198911003817100381710038171003817119871119902((0119879)119861
119904minus2+(2119902)120573
119901119903(R119889+1+
))]
(151)
If in addition 119903 lt infin then 119906 isin 119862([0 119879] 119861119904120573119901119903(R119889+1
+))
Proof Since 119892 119891 are tempered (76) has a unique solution 119906in S1015840
((0 119879) timesR119889+1
+) satisfying
F119882 (119906) (119905 120585) = 119890minus1199051205852
F119882 (119892) (120585)
+ int
119905
0
119890(120591minus119905)120585
2
F119882 (119891) (120591 120585) 119889120591
(152)
Hence applying Δ 119895 119895 ge 0 to (81) we see that
Δ 119895119906 (119905 sdot) = 119867120573 (119905) Δ 119895119892 + int
119905
0
119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot) 119889120591(153)
and thus by Lemma 30 we can deduce that10038171003817100381710038171003817Δ 119895119906 (119905 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
le
10038171003817100381710038171003817119867120573(119905)Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)+ int
119905
0
10038171003817100381710038171003817119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591
le 119862[119890minus1205812211989511990510038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+int
119905
0
119890minus12058122119895(119905minus120591)10038171003817
100381710038171003817Δ 119895119891(120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591]
(154)
Then it follows from convolution inequalities thatΔ 1198951199061198711199021 ((0119879)119871
119901
120573(R119889+1+
))is dominated by
(
1 minus 119890minus120581119879119902122119895
120581119902122119895
)
11199021
10038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119861119904120573
119901119903(R119889+1+
)
+ (
1 minus 119890minus120581119879119902222119895
120581119902222119895
)
11199022
10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119902((0119879)119871
119901
120573(R119889+1+
))
(155)
with 11199022 = 1 + 11199021 minus 1119902 Moreover similarly as above wecan obtain that
1003817100381710038171003817Δminus1119906(119905 sdot)
1003817100381710038171003817119871119901
120573(R119889+1+
)le1003817100381710038171003817Δminus1119892
1003817100381710038171003817119871119901
120573(R119889+1+
)
+ int
119905
0
1003817100381710038171003817Δminus1119891 (120591 sdot)
1003817100381710038171003817119871119901
120573(R119889+1+
)119889120591
(156)
and thus if 1 le 119902 le 1199021 le infin1003817100381710038171003817Δminus1119906
10038171003817100381710038171198711199021 ((0119879)119871
119901
120573(R119889+1+
))
le 119862(119879111990211003817100381710038171003817Δminus1119892
1003817100381710038171003817119871119901
120573(R119889+1+
)+ 119879
111990221003817100381710038171003817Δminus1119891
1003817100381710038171003817119871119902((0119879)119871
119901
120573(R119889+1+
)))
(157)
Journal of Function Spaces and Applications 13
Finally taking the 119897119903-normwith respect to 119895 in (155) and (157)with the usual convention if 119903 = infin we can deduce the desiredestimate
Acknowledgment
Theauthor gratefully acknowledges theDeanship of ScientificResearch at the University of Taibah The author is deeplyindebted to the referee for providing constructive commentsand help in improving the contents of this paper
References
[1] Z Ben Nahia and N Ben Salem ldquoSpherical harmonics andapplications associated with the Weinstein operatorrdquo in Pro-ceedings of the International Conference on PotentialTheory heldin Kouty Czech Republic (ICPT rsquo94) pp 235ndash241 1996
[2] Z Ben Nahia and N Ben Salem ldquoOn a mean value propertyassociated with the Weinstein operatorrdquo in Proceedings of theInternational Conference on Potential Theory held in KoutyCzech Republic (ICPT rsquo94) pp 243ndash253 1996
[3] M Brelot ldquoEquation de Weinstein et potentiels de MarcelRieszrdquo in Seminaire de Theorie de Potentiel Paris No 3 vol 681of Lecture Notes in Mathematics pp 18ndash38 Springer BerlinGermany 1978
[4] H Mejjaoli and M Salhi ldquoUncertainty principles for theweinstein transformrdquo Czechoslovak Mathematical Journal vol61 no 4 pp 941ndash974 2011
[5] H Mejjaoli and A Ould Ahmed Salem ldquoWeinstein Gabortransform and applicationsrdquo Advanced Studies in Pure Mathe-matics vol 2 no 3 pp 203ndash210 2012
[6] H Mejjaoli ldquoBesov spaces associated withthe Weinstein opera-tor and applicationsrdquo In press
[7] T Kawazoe and H Mejjaoli ldquoGeneralized Besov spaces andtheir applicationsrdquo Tokyo Journal of Mathematics vol 35 no 2pp 297ndash320 2012
[8] H Mejjaoli ldquoLittlewood-Paley decomposition associated withthe Dunkl operators and paraproduct operatorsrdquo Journal ofInequalities in Pure and Applied Mathematics vol 9 no 4 pp1ndash25 2008
[9] H Mejjaoli and N Sraeib ldquoGeneralized sobolev spaces inquantum calculus and applicationsrdquo Journal of Inequalities andSpecial Functions vol 1 no 4 pp 43ndash64 2012
[10] H Mejjaoli ldquoGeneralized homogeneous Besov spaces and theirapplicationsrdquo Serdica Mathematical Journal vol 38 no 4 pp575ndash614 2012
[11] H Triebel Interpolation Theory Functions Spaces DifferentialOperators North-Holland AmsterdamThe Netherlands 1978
[12] V S Guliev ldquoOn maximal function and fractional integralassociated with the Bessel differential operatorrdquo MathematicalInequalities and Applications vol 6 no 2 pp 317ndash330 2003
Submit your manuscripts athttpwwwhindawicom
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
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Differential EquationsInternational Journal of
Volume 2014
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Probability and StatisticsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
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Mathematical PhysicsAdvances in
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CombinatoricsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
International Journal of
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Operations ResearchAdvances in
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Function Spaces
Abstract and Applied AnalysisHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
International Journal of Mathematics and Mathematical Sciences
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Algebra
Discrete Dynamics in Nature and Society
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
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Decision SciencesAdvances in
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Volume 2014 Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Stochastic AnalysisInternational Journal of
Journal of Function Spaces and Applications 11
Indeed we use the following identity (which may be easilyproven by taking the Weinstein transform in 119909 of both sides)
(minusΔ 120573)
minus1205752
119891 (119909) =
1
Γ (1205752)
int
infin
0
1199051205752minus1
119867120573 (119905) 119891 (119909) 119889119905 (133)
with 120575 = 1199041 minus 119904 gt 0We decompose the integral in two parts as follows
(minusΔ 120573)
minus1205752
119891 (119909) =
1
Γ (1205752)
int
119879
0
1199051205752minus1
119867120573 (119905) 119891 (119909) 119889119905
+
1
Γ (1205752)
int
infin
119879
1199051205752minus1
119867120573 (119905) 119891 (119909) 119889119905
(134)
where 119879 is a constant to be fixed laterWe proceed as in [8] we obtain
10038161003816100381610038161003816119867120573 (119905) 119891 (119909)
10038161003816100381610038161003816le 119862119872120573 (119891) (119909) (135)
On the other hand we use Theorem 29 and the fact that 119891belongs to Bminus120573minus119904
1120573
infininfin(R119889+1
+) to deduce that
10038161003816100381610038161003816119867120573 (119905) 119891 (119909)
10038161003816100381610038161003816le 119862119905
(minus120573minus1199041)210038171003817100381710038171198911003817100381710038171003817Bminus120573minus1199041120573
infininfin (R119889+1+
) (136)
Thus by applying the preceding estimates on the right part of(134) we obtain
1003816100381610038161003816100381610038161003816
(minusΔ 120573)
minus1205752
119891 (119909)
1003816100381610038161003816100381610038161003816
le
1198621
Γ (1205752)
1198791205752119872120573 (119891) (119909)
+
1198622
Γ (1205752)
119879(120575minus120573minus119904
1)210038171003817100381710038171198911003817100381710038171003817Bminus120573minus1199041120573
infininfin (R119889+1+
)
(137)
We fix now
119879 = (
10038171003817100381710038171198911003817100381710038171003817Bminus120573minus1199041120573
infininfin (R119889+1+
)
119872120573 (119891) (119909)
)
2(120573+1199041)
(138)
We obtain
1003816100381610038161003816100381610038161003816
(minusΔ120573)
minus1205752
119891 (119909)
1003816100381610038161003816100381610038161003816
le
1198621 + 1198622
Γ (1205752)
(119872120573(119891)(119909))
12057910038171003817100381710038171198911003817100381710038171003817
1minus120579
Bminus120573minus1199041120573
infininfin (R119889+1+
)
(139)
Thus we deduce that1003817100381710038171003817100381710038171003817
(minusΔ120573)
minus1205752
119891
1003817100381710038171003817100381710038171003817119871119902
120573(R119889+1+
)
le
1198621 + 1198622
Γ (1205752)
10038171003817100381710038171003817119872120573 (119891)
10038171003817100381710038171003817
120579
119871119901
120573(R119889+1+
)
10038171003817100381710038171198911003817100381710038171003817
1minus120579
Bminus120573minus1199041120573
infininfin (R119889+1+
)
(140)
To conclude we used the fact that the maximal function119872120573
is bounded of 119871119902120573(R119889+1
+) into itself for 119902 gt 1
43 Estimates in Generalized Besov Spaces For any interval 119868ofR (bounded or unbounded) and a normed space 119865(R119889+1
+)
we define the mixed space-time 119871119901(119868 119865(R119889+1
+)) space of
(classes of) measurable functions 119906 119868 rarr 119865(R119889+1
+) such that
||119906||119871119901(119868119865(R119889+1+
)) lt infin with
119906119871119901(119868119865(R119889+1+
)) = (int
119868
119906 (119905 sdot)119901
119865(R119889+1+
)119889119905)
1119901
if 1 le 119901 lt infin
119906119871infin(119868119865(R119889+1+
)) = ess sup119905isin119868
119906 (119905 sdot)119865(R119889+1+
)
(141)
For any interval 119868 of R (bounded or unbounded) anda Banach space 119883 we define the mixed space-time 119862(119868119883)space of continuous functions 119868 rarr 119883 When 119868 is bounded119862(119868119883) is a Banach space with the norm of 119871infin(119868 119883)
Theorem 33 Let 119904 isin R and 1 le 119901 119902 119903 le infin Let 119879 gt 0 119892 isin
B119904120573
119901119903(R119889+1
+) and119891 in 119871119902((0 119879) B
119904minus2+(2119902)120573
119901119903 (R119889+1
+)) Then (76)
has a unique solution
119906 isin 119871119902((0 119879)
B119904+(2119902)120573
119901119903(R
119889+1
+))
⋂119871infin((0 119879)
B119904120573
119901119903(R
119889+1
+))
(142)
and there exists a constant 119862 such that for all 1199021 isin [119902infin] onehas
1199061198711199021 ((0119879)B
119904+(21199021)120573
119901119903(R119889+1+
))
le 119862(10038171003817100381710038171198921003817100381710038171003817B119904120573
119901119903(R119889+1+
)+10038171003817100381710038171198911003817100381710038171003817119871119902((0119879)B
119904minus2+(2119902)120573
119901119903(R119889+1+
)))
(143)
If in addition 119903 lt infin then 119906 isin 119862([0 119879] B119904120573
119901119903(R119889+1
+))
Proof Since 119892 and 119891 are temperate distributions (76) has aunique solution 119906 in S1015840
((0 119879) timesR119889+1
+) which satisfies
F119882 (119906) (119905 120585) = 119890minus1199051205852
F119882 (119892) (120585)
+ int
119905
0
119890(120591minus119905)120585
2
F119882 (119891) (120591 120585) 119889120591
(144)
Next we notice that applying Δ 119895 to (76) and using formula(81) yield
Δ 119895119906 (119905 sdot) = 119867120573 (119905) Δ 119895119892 + int
119905
0
119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot) 119889120591(145)
Therefore
10038171003817100381710038171003817Δ 119895119906 (119905 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)le
10038171003817100381710038171003817119867120573(119905)Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+ int
119905
0
10038171003817100381710038171003817119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591
(146)
12 Journal of Function Spaces and Applications
By virtue of Lemma 30 we thus have for some 120581 gt 0
10038171003817100381710038171003817Δ 119895119906(119905 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
le 119862[119890minus1205812211989511990510038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+ int
119905
0
119890minus12058122119895(119905minus120591) 10038171003817
100381710038171003817Δ 119895119891 (120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591]
(147)
Applying convolution inequalities we get
10038171003817100381710038171003817Δ 119895119906
100381710038171003817100381710038171198711199021 ((0119879)119871
119901
120573(R119889+1+
))
le 119862[
[
((
1 minus 119890minus120581119879119902122119895
120581119902122119895
)
11199021
)
10038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+((
1 minus 119890minus120581119879119902222119895
120581119902222119895
)
11199022
)
10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119902((0119879)119871
119901
120573(R119889+1+
))
]
]
(148)
with 11199022 = 1+ 11199021 minus1119902 Finally taking the 119897119903(Z) norm we
conclude that (with the usual convention if 119903 = infin)
1199061198711199021 ((0119879)B
119904+(21199021)120573
119901119903(R119889+1+
))
le 119862[
[
sum
119895isinZ
((
1 minus 119890minus120581119879119902122119895
120581119902122119895
)
1199031199021
)(211989511990410038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
]
]
1119903
+ 119862[
[
sum
119895isinZ
((
1 minus 119890minus120581119879119902222119895
120581119902222119895
)
1199031199022
)
times (2119895(119904minus2+2119902)10038171003817
100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119902(0119879119871
119901
120573(R119889+1+
))
119903
]
]
1119903
(149)
which insures that 119906 isin 119871119902((0 119879)
B119904+(2119902)120573
119901119903 (R119889+1
+))
⋂119871infin((0 119879)
B119904120573
119901119903(R119889+1
+)) and yields the desired inequality
Since 119906 belongs to 119862([0 119879]B119904120573
119901119903(R119889+1
+)) in the case where
119903 is finite may be easily deduced from the density ofSlowast(R
119889+1)⋂
B119904120573
119901119903(R119889+1
+) in B
119904120573
119901119903(R)
Theorem 34 Let 119904 isin R 119879 gt 0 and 1 le 119901 119902 119903 le infinOne supposes that 119892 isin 119861
119904120573
119901119903(R119889+1
+) and 119891 isin 119871
119902((0 119879)
119861119904minus2+(2119902)120573
119901119903 (R119889+1
+)) Then (76) has a unique solution 119906 belong-
ing to
119871119902((0 119879) 119861
119904+(2119902)120573
119901119903(R
119889+1
+))⋂119871
infin((0 119879) 119861
119904120573
119901119903(R
119889+1
+))
(150)
and there exists a constant 119862 such that for all 119902 le 1199021 le infin
1199061198711199021 ((0119879)119861
119904+(21199021)120573
119901119903(R119889+1+
))
le 119862 [ (1 + 11987911199021)10038171003817100381710038171198921003817100381710038171003817119861119904120573
119901119903(R119889+1+
)
+ (1 + 1198791+1119902
1minus1119902
)10038171003817100381710038171198911003817100381710038171003817119871119902((0119879)119861
119904minus2+(2119902)120573
119901119903(R119889+1+
))]
(151)
If in addition 119903 lt infin then 119906 isin 119862([0 119879] 119861119904120573119901119903(R119889+1
+))
Proof Since 119892 119891 are tempered (76) has a unique solution 119906in S1015840
((0 119879) timesR119889+1
+) satisfying
F119882 (119906) (119905 120585) = 119890minus1199051205852
F119882 (119892) (120585)
+ int
119905
0
119890(120591minus119905)120585
2
F119882 (119891) (120591 120585) 119889120591
(152)
Hence applying Δ 119895 119895 ge 0 to (81) we see that
Δ 119895119906 (119905 sdot) = 119867120573 (119905) Δ 119895119892 + int
119905
0
119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot) 119889120591(153)
and thus by Lemma 30 we can deduce that10038171003817100381710038171003817Δ 119895119906 (119905 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
le
10038171003817100381710038171003817119867120573(119905)Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)+ int
119905
0
10038171003817100381710038171003817119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591
le 119862[119890minus1205812211989511990510038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+int
119905
0
119890minus12058122119895(119905minus120591)10038171003817
100381710038171003817Δ 119895119891(120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591]
(154)
Then it follows from convolution inequalities thatΔ 1198951199061198711199021 ((0119879)119871
119901
120573(R119889+1+
))is dominated by
(
1 minus 119890minus120581119879119902122119895
120581119902122119895
)
11199021
10038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119861119904120573
119901119903(R119889+1+
)
+ (
1 minus 119890minus120581119879119902222119895
120581119902222119895
)
11199022
10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119902((0119879)119871
119901
120573(R119889+1+
))
(155)
with 11199022 = 1 + 11199021 minus 1119902 Moreover similarly as above wecan obtain that
1003817100381710038171003817Δminus1119906(119905 sdot)
1003817100381710038171003817119871119901
120573(R119889+1+
)le1003817100381710038171003817Δminus1119892
1003817100381710038171003817119871119901
120573(R119889+1+
)
+ int
119905
0
1003817100381710038171003817Δminus1119891 (120591 sdot)
1003817100381710038171003817119871119901
120573(R119889+1+
)119889120591
(156)
and thus if 1 le 119902 le 1199021 le infin1003817100381710038171003817Δminus1119906
10038171003817100381710038171198711199021 ((0119879)119871
119901
120573(R119889+1+
))
le 119862(119879111990211003817100381710038171003817Δminus1119892
1003817100381710038171003817119871119901
120573(R119889+1+
)+ 119879
111990221003817100381710038171003817Δminus1119891
1003817100381710038171003817119871119902((0119879)119871
119901
120573(R119889+1+
)))
(157)
Journal of Function Spaces and Applications 13
Finally taking the 119897119903-normwith respect to 119895 in (155) and (157)with the usual convention if 119903 = infin we can deduce the desiredestimate
Acknowledgment
Theauthor gratefully acknowledges theDeanship of ScientificResearch at the University of Taibah The author is deeplyindebted to the referee for providing constructive commentsand help in improving the contents of this paper
References
[1] Z Ben Nahia and N Ben Salem ldquoSpherical harmonics andapplications associated with the Weinstein operatorrdquo in Pro-ceedings of the International Conference on PotentialTheory heldin Kouty Czech Republic (ICPT rsquo94) pp 235ndash241 1996
[2] Z Ben Nahia and N Ben Salem ldquoOn a mean value propertyassociated with the Weinstein operatorrdquo in Proceedings of theInternational Conference on Potential Theory held in KoutyCzech Republic (ICPT rsquo94) pp 243ndash253 1996
[3] M Brelot ldquoEquation de Weinstein et potentiels de MarcelRieszrdquo in Seminaire de Theorie de Potentiel Paris No 3 vol 681of Lecture Notes in Mathematics pp 18ndash38 Springer BerlinGermany 1978
[4] H Mejjaoli and M Salhi ldquoUncertainty principles for theweinstein transformrdquo Czechoslovak Mathematical Journal vol61 no 4 pp 941ndash974 2011
[5] H Mejjaoli and A Ould Ahmed Salem ldquoWeinstein Gabortransform and applicationsrdquo Advanced Studies in Pure Mathe-matics vol 2 no 3 pp 203ndash210 2012
[6] H Mejjaoli ldquoBesov spaces associated withthe Weinstein opera-tor and applicationsrdquo In press
[7] T Kawazoe and H Mejjaoli ldquoGeneralized Besov spaces andtheir applicationsrdquo Tokyo Journal of Mathematics vol 35 no 2pp 297ndash320 2012
[8] H Mejjaoli ldquoLittlewood-Paley decomposition associated withthe Dunkl operators and paraproduct operatorsrdquo Journal ofInequalities in Pure and Applied Mathematics vol 9 no 4 pp1ndash25 2008
[9] H Mejjaoli and N Sraeib ldquoGeneralized sobolev spaces inquantum calculus and applicationsrdquo Journal of Inequalities andSpecial Functions vol 1 no 4 pp 43ndash64 2012
[10] H Mejjaoli ldquoGeneralized homogeneous Besov spaces and theirapplicationsrdquo Serdica Mathematical Journal vol 38 no 4 pp575ndash614 2012
[11] H Triebel Interpolation Theory Functions Spaces DifferentialOperators North-Holland AmsterdamThe Netherlands 1978
[12] V S Guliev ldquoOn maximal function and fractional integralassociated with the Bessel differential operatorrdquo MathematicalInequalities and Applications vol 6 no 2 pp 317ndash330 2003
Submit your manuscripts athttpwwwhindawicom
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
MathematicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Mathematical Problems in Engineering
Hindawi Publishing Corporationhttpwwwhindawicom
Differential EquationsInternational Journal of
Volume 2014
Applied MathematicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Probability and StatisticsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Mathematical PhysicsAdvances in
Complex AnalysisJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
OptimizationJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
CombinatoricsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
International Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Operations ResearchAdvances in
Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Function Spaces
Abstract and Applied AnalysisHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
International Journal of Mathematics and Mathematical Sciences
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Algebra
Discrete Dynamics in Nature and Society
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Decision SciencesAdvances in
Discrete MathematicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom
Volume 2014 Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Stochastic AnalysisInternational Journal of
12 Journal of Function Spaces and Applications
By virtue of Lemma 30 we thus have for some 120581 gt 0
10038171003817100381710038171003817Δ 119895119906(119905 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
le 119862[119890minus1205812211989511990510038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+ int
119905
0
119890minus12058122119895(119905minus120591) 10038171003817
100381710038171003817Δ 119895119891 (120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591]
(147)
Applying convolution inequalities we get
10038171003817100381710038171003817Δ 119895119906
100381710038171003817100381710038171198711199021 ((0119879)119871
119901
120573(R119889+1+
))
le 119862[
[
((
1 minus 119890minus120581119879119902122119895
120581119902122119895
)
11199021
)
10038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+((
1 minus 119890minus120581119879119902222119895
120581119902222119895
)
11199022
)
10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119902((0119879)119871
119901
120573(R119889+1+
))
]
]
(148)
with 11199022 = 1+ 11199021 minus1119902 Finally taking the 119897119903(Z) norm we
conclude that (with the usual convention if 119903 = infin)
1199061198711199021 ((0119879)B
119904+(21199021)120573
119901119903(R119889+1+
))
le 119862[
[
sum
119895isinZ
((
1 minus 119890minus120581119879119902122119895
120581119902122119895
)
1199031199021
)(211989511990410038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
))
119903
]
]
1119903
+ 119862[
[
sum
119895isinZ
((
1 minus 119890minus120581119879119902222119895
120581119902222119895
)
1199031199022
)
times (2119895(119904minus2+2119902)10038171003817
100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119902(0119879119871
119901
120573(R119889+1+
))
119903
]
]
1119903
(149)
which insures that 119906 isin 119871119902((0 119879)
B119904+(2119902)120573
119901119903 (R119889+1
+))
⋂119871infin((0 119879)
B119904120573
119901119903(R119889+1
+)) and yields the desired inequality
Since 119906 belongs to 119862([0 119879]B119904120573
119901119903(R119889+1
+)) in the case where
119903 is finite may be easily deduced from the density ofSlowast(R
119889+1)⋂
B119904120573
119901119903(R119889+1
+) in B
119904120573
119901119903(R)
Theorem 34 Let 119904 isin R 119879 gt 0 and 1 le 119901 119902 119903 le infinOne supposes that 119892 isin 119861
119904120573
119901119903(R119889+1
+) and 119891 isin 119871
119902((0 119879)
119861119904minus2+(2119902)120573
119901119903 (R119889+1
+)) Then (76) has a unique solution 119906 belong-
ing to
119871119902((0 119879) 119861
119904+(2119902)120573
119901119903(R
119889+1
+))⋂119871
infin((0 119879) 119861
119904120573
119901119903(R
119889+1
+))
(150)
and there exists a constant 119862 such that for all 119902 le 1199021 le infin
1199061198711199021 ((0119879)119861
119904+(21199021)120573
119901119903(R119889+1+
))
le 119862 [ (1 + 11987911199021)10038171003817100381710038171198921003817100381710038171003817119861119904120573
119901119903(R119889+1+
)
+ (1 + 1198791+1119902
1minus1119902
)10038171003817100381710038171198911003817100381710038171003817119871119902((0119879)119861
119904minus2+(2119902)120573
119901119903(R119889+1+
))]
(151)
If in addition 119903 lt infin then 119906 isin 119862([0 119879] 119861119904120573119901119903(R119889+1
+))
Proof Since 119892 119891 are tempered (76) has a unique solution 119906in S1015840
((0 119879) timesR119889+1
+) satisfying
F119882 (119906) (119905 120585) = 119890minus1199051205852
F119882 (119892) (120585)
+ int
119905
0
119890(120591minus119905)120585
2
F119882 (119891) (120591 120585) 119889120591
(152)
Hence applying Δ 119895 119895 ge 0 to (81) we see that
Δ 119895119906 (119905 sdot) = 119867120573 (119905) Δ 119895119892 + int
119905
0
119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot) 119889120591(153)
and thus by Lemma 30 we can deduce that10038171003817100381710038171003817Δ 119895119906 (119905 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
le
10038171003817100381710038171003817119867120573(119905)Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)+ int
119905
0
10038171003817100381710038171003817119867120573 (119905 minus 120591) Δ 119895119891 (120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591
le 119862[119890minus1205812211989511990510038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119871119901
120573(R119889+1+
)
+int
119905
0
119890minus12058122119895(119905minus120591)10038171003817
100381710038171003817Δ 119895119891(120591 sdot)
10038171003817100381710038171003817119871119901
120573(R119889+1+
)119889120591]
(154)
Then it follows from convolution inequalities thatΔ 1198951199061198711199021 ((0119879)119871
119901
120573(R119889+1+
))is dominated by
(
1 minus 119890minus120581119879119902122119895
120581119902122119895
)
11199021
10038171003817100381710038171003817Δ 119895119892
10038171003817100381710038171003817119861119904120573
119901119903(R119889+1+
)
+ (
1 minus 119890minus120581119879119902222119895
120581119902222119895
)
11199022
10038171003817100381710038171003817Δ 119895119891
10038171003817100381710038171003817119871119902((0119879)119871
119901
120573(R119889+1+
))
(155)
with 11199022 = 1 + 11199021 minus 1119902 Moreover similarly as above wecan obtain that
1003817100381710038171003817Δminus1119906(119905 sdot)
1003817100381710038171003817119871119901
120573(R119889+1+
)le1003817100381710038171003817Δminus1119892
1003817100381710038171003817119871119901
120573(R119889+1+
)
+ int
119905
0
1003817100381710038171003817Δminus1119891 (120591 sdot)
1003817100381710038171003817119871119901
120573(R119889+1+
)119889120591
(156)
and thus if 1 le 119902 le 1199021 le infin1003817100381710038171003817Δminus1119906
10038171003817100381710038171198711199021 ((0119879)119871
119901
120573(R119889+1+
))
le 119862(119879111990211003817100381710038171003817Δminus1119892
1003817100381710038171003817119871119901
120573(R119889+1+
)+ 119879
111990221003817100381710038171003817Δminus1119891
1003817100381710038171003817119871119902((0119879)119871
119901
120573(R119889+1+
)))
(157)
Journal of Function Spaces and Applications 13
Finally taking the 119897119903-normwith respect to 119895 in (155) and (157)with the usual convention if 119903 = infin we can deduce the desiredestimate
Acknowledgment
Theauthor gratefully acknowledges theDeanship of ScientificResearch at the University of Taibah The author is deeplyindebted to the referee for providing constructive commentsand help in improving the contents of this paper
References
[1] Z Ben Nahia and N Ben Salem ldquoSpherical harmonics andapplications associated with the Weinstein operatorrdquo in Pro-ceedings of the International Conference on PotentialTheory heldin Kouty Czech Republic (ICPT rsquo94) pp 235ndash241 1996
[2] Z Ben Nahia and N Ben Salem ldquoOn a mean value propertyassociated with the Weinstein operatorrdquo in Proceedings of theInternational Conference on Potential Theory held in KoutyCzech Republic (ICPT rsquo94) pp 243ndash253 1996
[3] M Brelot ldquoEquation de Weinstein et potentiels de MarcelRieszrdquo in Seminaire de Theorie de Potentiel Paris No 3 vol 681of Lecture Notes in Mathematics pp 18ndash38 Springer BerlinGermany 1978
[4] H Mejjaoli and M Salhi ldquoUncertainty principles for theweinstein transformrdquo Czechoslovak Mathematical Journal vol61 no 4 pp 941ndash974 2011
[5] H Mejjaoli and A Ould Ahmed Salem ldquoWeinstein Gabortransform and applicationsrdquo Advanced Studies in Pure Mathe-matics vol 2 no 3 pp 203ndash210 2012
[6] H Mejjaoli ldquoBesov spaces associated withthe Weinstein opera-tor and applicationsrdquo In press
[7] T Kawazoe and H Mejjaoli ldquoGeneralized Besov spaces andtheir applicationsrdquo Tokyo Journal of Mathematics vol 35 no 2pp 297ndash320 2012
[8] H Mejjaoli ldquoLittlewood-Paley decomposition associated withthe Dunkl operators and paraproduct operatorsrdquo Journal ofInequalities in Pure and Applied Mathematics vol 9 no 4 pp1ndash25 2008
[9] H Mejjaoli and N Sraeib ldquoGeneralized sobolev spaces inquantum calculus and applicationsrdquo Journal of Inequalities andSpecial Functions vol 1 no 4 pp 43ndash64 2012
[10] H Mejjaoli ldquoGeneralized homogeneous Besov spaces and theirapplicationsrdquo Serdica Mathematical Journal vol 38 no 4 pp575ndash614 2012
[11] H Triebel Interpolation Theory Functions Spaces DifferentialOperators North-Holland AmsterdamThe Netherlands 1978
[12] V S Guliev ldquoOn maximal function and fractional integralassociated with the Bessel differential operatorrdquo MathematicalInequalities and Applications vol 6 no 2 pp 317ndash330 2003
Submit your manuscripts athttpwwwhindawicom
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
MathematicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Mathematical Problems in Engineering
Hindawi Publishing Corporationhttpwwwhindawicom
Differential EquationsInternational Journal of
Volume 2014
Applied MathematicsJournal of
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Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Mathematical PhysicsAdvances in
Complex AnalysisJournal of
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OptimizationJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
CombinatoricsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
International Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Operations ResearchAdvances in
Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Function Spaces
Abstract and Applied AnalysisHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
International Journal of Mathematics and Mathematical Sciences
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Algebra
Discrete Dynamics in Nature and Society
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Decision SciencesAdvances in
Discrete MathematicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom
Volume 2014 Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Stochastic AnalysisInternational Journal of
Journal of Function Spaces and Applications 13
Finally taking the 119897119903-normwith respect to 119895 in (155) and (157)with the usual convention if 119903 = infin we can deduce the desiredestimate
Acknowledgment
Theauthor gratefully acknowledges theDeanship of ScientificResearch at the University of Taibah The author is deeplyindebted to the referee for providing constructive commentsand help in improving the contents of this paper
References
[1] Z Ben Nahia and N Ben Salem ldquoSpherical harmonics andapplications associated with the Weinstein operatorrdquo in Pro-ceedings of the International Conference on PotentialTheory heldin Kouty Czech Republic (ICPT rsquo94) pp 235ndash241 1996
[2] Z Ben Nahia and N Ben Salem ldquoOn a mean value propertyassociated with the Weinstein operatorrdquo in Proceedings of theInternational Conference on Potential Theory held in KoutyCzech Republic (ICPT rsquo94) pp 243ndash253 1996
[3] M Brelot ldquoEquation de Weinstein et potentiels de MarcelRieszrdquo in Seminaire de Theorie de Potentiel Paris No 3 vol 681of Lecture Notes in Mathematics pp 18ndash38 Springer BerlinGermany 1978
[4] H Mejjaoli and M Salhi ldquoUncertainty principles for theweinstein transformrdquo Czechoslovak Mathematical Journal vol61 no 4 pp 941ndash974 2011
[5] H Mejjaoli and A Ould Ahmed Salem ldquoWeinstein Gabortransform and applicationsrdquo Advanced Studies in Pure Mathe-matics vol 2 no 3 pp 203ndash210 2012
[6] H Mejjaoli ldquoBesov spaces associated withthe Weinstein opera-tor and applicationsrdquo In press
[7] T Kawazoe and H Mejjaoli ldquoGeneralized Besov spaces andtheir applicationsrdquo Tokyo Journal of Mathematics vol 35 no 2pp 297ndash320 2012
[8] H Mejjaoli ldquoLittlewood-Paley decomposition associated withthe Dunkl operators and paraproduct operatorsrdquo Journal ofInequalities in Pure and Applied Mathematics vol 9 no 4 pp1ndash25 2008
[9] H Mejjaoli and N Sraeib ldquoGeneralized sobolev spaces inquantum calculus and applicationsrdquo Journal of Inequalities andSpecial Functions vol 1 no 4 pp 43ndash64 2012
[10] H Mejjaoli ldquoGeneralized homogeneous Besov spaces and theirapplicationsrdquo Serdica Mathematical Journal vol 38 no 4 pp575ndash614 2012
[11] H Triebel Interpolation Theory Functions Spaces DifferentialOperators North-Holland AmsterdamThe Netherlands 1978
[12] V S Guliev ldquoOn maximal function and fractional integralassociated with the Bessel differential operatorrdquo MathematicalInequalities and Applications vol 6 no 2 pp 317ndash330 2003
Submit your manuscripts athttpwwwhindawicom
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
MathematicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Mathematical Problems in Engineering
Hindawi Publishing Corporationhttpwwwhindawicom
Differential EquationsInternational Journal of
Volume 2014
Applied MathematicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Probability and StatisticsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Mathematical PhysicsAdvances in
Complex AnalysisJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
OptimizationJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
CombinatoricsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
International Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Operations ResearchAdvances in
Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Function Spaces
Abstract and Applied AnalysisHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
International Journal of Mathematics and Mathematical Sciences
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Algebra
Discrete Dynamics in Nature and Society
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Decision SciencesAdvances in
Discrete MathematicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom
Volume 2014 Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Stochastic AnalysisInternational Journal of
Submit your manuscripts athttpwwwhindawicom
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
MathematicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Mathematical Problems in Engineering
Hindawi Publishing Corporationhttpwwwhindawicom
Differential EquationsInternational Journal of
Volume 2014
Applied MathematicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Probability and StatisticsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Mathematical PhysicsAdvances in
Complex AnalysisJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
OptimizationJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
CombinatoricsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
International Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Operations ResearchAdvances in
Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Function Spaces
Abstract and Applied AnalysisHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
International Journal of Mathematics and Mathematical Sciences
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Algebra
Discrete Dynamics in Nature and Society
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Decision SciencesAdvances in
Discrete MathematicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom
Volume 2014 Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Stochastic AnalysisInternational Journal of