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The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
The Major Problems in Particle Physicsand How We Hope to Address Them
• The standard model
• Testing the standard model
• Problems
• Beyond the standard model
• Where are we going?
NYS APS (October 15, 2004) Paul Langacker (Penn)
The Standard Model and Beyond
Fundamental Neutron Physics (October, 2005) Paul Langacker (FNAL/Penn/IAS)
The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
The New Standard Model
• Standard model, supplemented with neutrino mass (Dirac orMajorana):
SU(3)×SU(2)×U(1)×classical relativity
• Mathematically consistent field theory of strong, weak,electromagnetic interactions
• Gauge interactions correct to first approximation to 10−16 cm
• Complicated, free parameters, fine tunings ⇒must be new physics
WIN 05 (June 11, 2005) Paul Langacker (Penn)
The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
• Many special features usually not maintained in BSM
– mν = 0 in old standard model (need to add singlet fermion and/or
triplet Higgs and/or higher dimensional operator (HDO))
– Yukawa coupling h ∝ gm/MW ⇒ flavor conserving and smallfor light fermions (partially maintained in MSSM and simple 2HDM)
– No FCNC at tree level (Z or h); suppressed at loop level(SUSY loops; Z′ from strings, DSB)
– Suppressed off-diagonal #CP ; highly suppressed diagonal (EDMs)(SUSY loops, soft parameters, exotics)
– B, L conserved perturbatively (B − L non-perturbatively)(GUT (string) interactions, "Rp)
– New TeV scale interactions suggested by top-down(Z′, exotics, extended Higgs)
Physics at LHC (July 16, 2004) Paul Langacker (Penn)
The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
Quantum Chromodynamics (QCD)
Modern theory of the strong interactions
NYS APS (October 15, 2004) Paul Langacker (Penn)
10 16. Structure functions
Table 16.1: Lepton-nucleon and related hard-scattering processes and theirprimary sensitivity to the parton distributions that are probed.
Main PDFsProcess Subprocess Probed
!±N → !±X γ∗q → q g(x 0.01), q, q!+(!−)N → ν(ν)X W ∗q → q′
ν(ν)N → !−(!+)X W ∗q → q′
ν N → µ+µ−X W ∗s → c → µ+ s
pp → γX qg → γq g(x ∼ 0.4)pN → µ+µ−X qq → γ∗ q
pp, pn → µ+µ−X uu, dd → γ∗ u − d
ud, du → γ∗
ep, en → eπX γ∗q → q
pp → W → !±X ud → W u, d, u/d
pp → jet +X gg, qg, qq → 2j q, g(0.01 x 0.5)
all polarized PDFs. These polarized PDFs may be fully accessed via flavor tagging insemi-inclusive deep inelastic scattering. Fig. 16.5 shows several global analyses at a scaleof 2.5 GeV2 along with the data from semi-inclusive DIS.
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
x
x f
(x)
Figure 16.4: Distributions of x times the unpolarized parton distributions f(x)(where f = uv, dv, u, d, s, c, g) using the MRST2001 parameterization [29,13](withuncertainties for uv, dv, and g) at a scale µ2 = 10 GeV2.
June 16, 2004 14:04
Quantum Chromodynamics (QCD)
Modern theory of the strong interactions
• Quark model/ color/confinement
• Low energy symmetries(+ realization, breaking)(SU(3)L×SU(3)R)
• Hadronic models: Yukawa,Regge, dual resonance (→strings)
• Asymptotic freedom (weakcoupling at high energy)
Yoichiro Nambu Symposium (April 21, 2005) Paul Langacker (Penn)
The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
9. Quantum chromodynamics 7
0.1 0.12 0.14
Average
Hadronic Jets
Polarized DIS
Deep Inelastic Scattering (DIS)
! decays
Z width
Fragmentation
Spectroscopy (Lattice)
ep event shapes
Photo-production
" decay
e+e
- rates
#s(MZ)
Figure 9.1: Summary of the value of αs(MZ) from various processes. The valuesshown indicate the process and the measured value of αs extrapolated to µ = MZ .The error shown is the total error including theoretical uncertainties. The averagequoted in this report which comes from these measurements is also shown. See textfor discussion of errors.
extracted [44,45] are consistent with the theoretical estimates. If the nonperturbativeterms are omitted from the fit, the extracted value of αs(mτ ) decreases by ∼ 0.02.
For αs(mτ ) = 0.35 the perturbative series for Rτ is Rτ ∼ 3.058(1+0.112+0.064+0.036).The size (estimated error) of the nonperturbative term is 20% (7%) of the size of theorder α3
s term. The perturbation series is not very well convergent; if the order α3s term
is omitted, the extracted value of αs(mτ ) increases by 0.05. The order α4s term has been
estimated [46] and attempts made to resum the entire series [47,48]. These estimates canbe used to obtain an estimate of the errors due to these unknown terms [49,50]. Weassign an uncertainty of ±0.02 to αs(mτ ) from these sources.
Rτ can be extracted from the semi-leptonic branching ratio from the relationRτ = 1/(B(τ → eνν) − 1.97256); where B(τ → eνν) is measured directly or extractedfrom the lifetime, the muon mass, and the muon lifetime assuming universality of leptoncouplings. Using the average lifetime of 290.6 ± 1.1 fs and a τ mass of 1776.99 ± 0.29
September 8, 2004 15:07
9. Quantum chromodynamics 17
required, for example, to facilitate the extraction of CKM elements from measurementsof charm and bottom decay rates. See Ref. 169 for a recent review.
0
0.1
0.2
0.3
1 10 102
µ GeV
!s(µ
)
Figure 9.2: Summary of the values of αs(µ) at the values of µ where they aremeasured. The lines show the central values and the ±1σ limits of our average.The figure clearly shows the decrease in αs(µ) with increasing µ. The data are,in increasing order of µ, τ width, Υ decays, deep inelastic scattering, e+e− eventshapes at 22 GeV from the JADE data, shapes at TRISTAN at 58 GeV, Z width,and e+e− event shapes at 135 and 189 GeV.
9.13. Conclusions
The need for brevity has meant that many other important topics in QCDphenomenology have had to be omitted from this review. One should mention inparticular the study of exclusive processes (form factors, elastic scattering, . . .), thebehavior of quarks and gluons in nuclei, the spin properties of the theory, and QCDeffects in hadron spectroscopy.
We have focused on those high-energy processes which currently offer the mostquantitative tests of perturbative QCD. Figure 9.1 shows the values of αs(MZ) deduced
September 8, 2004 15:07
• Quark model/ color
• Low energy symmetries(+ realization, breaking)(SU(3)L×SU(3)R)
• Hadronic models: Yukawa,Regge, dual resonance (→strings)
• Asymptotic freedom (weakcoupling at low energy)
Relation of “running” αs at different scales
Yoichiro Nambu Symposium (April 21, 2005) Paul Langacker (Penn)
The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
Quantum Electrodynamics
Experiment Value of α−1 Difference from α−1(ae)
Deviation from gyromagnetic 137.035 999 58 (52) [3.8 × 10−9] –
ratio, ae = (g − 2)/2 for e−
ac Josephson effect 137.035 988 0 (51) [3.7 × 10−8] (0.116 ± 0.051) × 10−4
h/mn (mn is the neutron mass) 137.036 011 9 (51) [3.7 × 10−8] (−0.123 ± 0.051) × 10−4
from n beam
Hyperfine structure in 137.035 993 2 (83) [6.0 × 10−8] (0.064 ± 0.083) × 10−4
muonium, µ+e−
Cesium D1 line 137.035 992 4 (41) [3.0 × 10−8] (0.072 ± 0.041) × 10−4
Yoichiro Nambu Symposium (April 21, 2005) Paul Langacker (Penn)
Quantum Electrodynamics
Experiment Value of α−1 Difference from α−1(ae)
Deviation from gyromagnetic 137.035 999 58 (52) [3.8 × 10−9] –
ratio, ae = (g − 2)/2 for e−
ac Josephson effect 137.035 988 0 (51) [3.7 × 10−8] (0.116 ± 0.051) × 10−4
h/mn (mn is the neutron mass) 137.036 011 9 (51) [3.7 × 10−8] (−0.123 ± 0.051) × 10−4
from n beam
Hyperfine structure in 137.035 993 2 (83) [6.0 × 10−8] (0.064 ± 0.083) × 10−4
muonium, µ+e−
Cesium D1 line 137.035 992 4 (41) [3.0 × 10−8] (0.072 ± 0.041) × 10−4
Yoichiro Nambu Symposium (April 21, 2005) Paul Langacker (Penn)
The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
The Electroweak Theory
• QED and weak charged currentunified
• Weak neutral current predicted
• Stringent tests of wnc, Z-poleand beyond
• Fermion gauge and gauge selfinteractions
Yoichiro Nambu Symposium (April 21, 2005) Paul Langacker (Penn)
The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
10-2
10-1
1
10
75 100 125 150 175
LEP combined: e+e! " hadrons(#)
$s%
[GeV]
&hadro
n [n
b]
LEP1 $s%
´/%s%
> 0.10LEP2 $s
%´/%s%
> 0.10LEP2 $s
%´/%s%
> 0.85
The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
Measurement Fit |Omeas
!Ofit|/"
meas
0 1 2 3
0 1 2 3
#$had
(mZ)#$
(5)0.02758 ± 0.00035 0.02767
mZ [GeV]m
Z [GeV] 91.1875 ± 0.0021 91.1874
%Z [GeV]%
Z [GeV] 2.4952 ± 0.0023 2.4959
"had
[nb]"0
41.540 ± 0.037 41.478
Rl
Rl
20.767 ± 0.025 20.742
Afb
A0,l
0.01714 ± 0.00095 0.01643
Al(P
&)A
l(P
&) 0.1465 ± 0.0032 0.1480
Rb
Rb
0.21629 ± 0.00066 0.21579
Rc
Rc
0.1721 ± 0.0030 0.1723
Afb
A0,b
0.0992 ± 0.0016 0.1038
Afb
A0,c
0.0707 ± 0.0035 0.0742
Ab
Ab
0.923 ± 0.020 0.935
Ac
Ac
0.670 ± 0.027 0.668
Al(SLD)Al(SLD) 0.1513 ± 0.0021 0.1480
sin2'
effsin
2'
lept(Q
fb) 0.2324 ± 0.0012 0.2314
mW
[GeV]mW
[GeV] 80.410 ± 0.032 80.377
%W
[GeV]%W
[GeV] 2.123 ± 0.067 2.092
mt [GeV]mt [GeV] 172.7 ± 2.9 173.3
The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
• SM correct and unique to zerothapprox. (gauge principle, group,representations)
• SM correct at loop level (renormgauge theory; mt, αs, MH)
• TeV physics severely constrained(unification vs compositeness)
• Consistent with light elementaryHiggs
• Precise gauge couplings (gaugeunification)
Yoichiro Nambu Symposium (April 21, 2005) Paul Langacker (Penn)
0
1
2
3
4
5
6
10030 300
mH [GeV]
!"
2
Excluded
!#had
=!#(5)
0.02758±0.00035
0.02749±0.00012
incl. low Q2 data
Theory uncertainty
The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
-1.5
-1
-0.5
0
0.5
1
1.5
-1 -0.5 0 0.5 1 1.5 2
sin 2!
sol. w/ cos 2!
! 0
(excl. at CL "
0.95)
exclu
ded a
t CL " 0
.95
"
"
#
#
$md
$ms # $m
d
%K
%K
$Vub
/Vcb$
sin 2!
sol. w/ cos 2!
! 0
(excl. at CL "
0.95)
exclu
ded a
t CL " 0
.95
#
!"
&
'
excluded area has CL "
0.95
C K Mf i t t e r
EPS 2005
• Heavy B decays and CPviolation
– CKM (quark mixing) → CPbreaking
– Unitarity triangle
– Search for new physics
– Anomalies in electroweakpenguins?
– Baryogenesis?
• Universality?
– |Vud|2 + |Vus|2 + |Vub|2 = 1
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
Problems with the Standard Model
Lagrangian after symmetry breaking:
L = Lgauge + LHiggs +∑
i
ψi
(i !∂ − mi −
miH
ν
)ψi
−g
2√
2
(Jµ
W W −µ + Jµ†
W W +µ
)− eJµ
QAµ −g
2 cos θWJµ
ZZµ
Standard model: SU(2)×U(1) (extended to include ν masses) +QCD + general relativity
Mathematically consistent, renormalizable theory
Correct to 10−16 cm
Physics at LHC (July 16, 2004) Paul Langacker (Penn)
The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
However, too much arbitrariness and fine-tuning: O(27) parameters(+ 2 for Majorana ν) and electric charges
• Gauge Problem
– complicated gauge group with 3 couplings
– charge quantization (|qe| = |qp|) unexplained– Possible solutions: strings; grand unification; magnetic
monopoles (partial); anomaly constraints (partial)
• Fermion problem
– Fermion masses, mixings, families unexplained– Neutrino masses, nature? Probe of Planck/GUT scale?– CP violation inadequate to explain baryon asymmetry– Possible solutions: strings; brane worlds; family symmetries;
compositeness; radiative hierarchies. New sources of CPviolation.
Yoichiro Nambu Symposium (April 21, 2005) Paul Langacker (Penn)
The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
• Higgs/hierarchy problem
– Expect M2H = O(M2
W )– higher order corrections:
δM2H/M2
W ∼ 1034
Possible solutions: supersymmetry; dynamical symmetry breaking;large extra dimensions; Little Higgs; anthropically motivated fine-tuning (split supersymmetry) (landscape)
• Strong CP problem
– Can add θ32π2g
2sF F to QCD (breaks, P, T, CP)
– dN ⇒ θ < 10−9, but δθ|weak ∼ 10−3
– Possible solutions: spontaneously broken global U(1) (Peccei-Quinn) ⇒ axion; unbroken global U(1) (massless u quark);spontaneously broken CP + other symmetries
Yoichiro Nambu Symposium (April 21, 2005) Paul Langacker (Penn)
The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
• Graviton problem
– gravity not unified
– quantum gravity not renormalizable
– cosmological constant: ΛSSB = 8πGN〈V 〉 > 1050Λobs (10124
for GUTs, strings)– Possible solutions:
∗ supergravity and Kaluza Klein unify∗ strings yield finite gravity.∗ Λ? Anthropically motivated fine-tuning (landscape)?
Yoichiro Nambu Symposium (April 21, 2005) Paul Langacker (Penn)
The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
• Necessary new ingredients
– Mechanism for small neutrino masses
∗ Planck/GUT scale?
– Mechanism for baryon asymmetry?
∗ Electroweak transition (Z′ or extended Higgs?)
∗ Heavy Majorana neutrino decay (seesaw)?
∗ Decay of coherent field? CPT violation?
NYS APS (October 15, 2004) Paul Langacker (Penn)
The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
– What is the dark energy?
∗ Cosmological Constant? Quintessence?
∗ Related to inflation? Time variation of couplings?
– What is the dark matter?
∗ Lightest supersymmetric particle? Axion?
– Suppression of flavor changing neutral currents? Proton decay?Electric dipole moments?∗ Automatic in standard model, but not in extensions
NYS APS (October 15, 2004) Paul Langacker (Penn)
The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
Beyond the Standard Model
• The Whimper: A new layer at the TeV scale
• The Hybrid: low fundamental scale/large extra dimensions
• The Bang: unification at the Planck scale, MP = G−1/2N ∼ 1019
GeV
NYS APS (October 15, 2004) Paul Langacker (Penn)
The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
TypicalModel scale (GeV) MotivationNew W s, Zs, fermions, Higgs 102–1019 Remnant of something else
Family symmetry 102–1019 Fermion (No compelling models)
Composite fermions 102–1019 Fermion (No compelling models)Composite Higgs 103–104 Higgs (No compelling models)Composite W , Z (G, γ?) 103–104 Higgs (No compelling models)Little Higgs 103–104 Higgs
Large extra dimensions (d > 4) 103–106 Higgs, graviton
New global symmetry 108–1012 Strong CP
Kaluza–Klein 1019 GravitonHiggs (0) ⇔ gauge (1) ⇔
Graviton (2) (d > 4)
Grand unification 1014–1019 GaugeStrong ⇔ electroweak
Supersymmetry/supergravity 102–1019 Higgs, gravitonFermion ⇔ boson
Superstrings 1019 All problems!?Strong ⇔ electroweak ⇔
gravityFermion ⇔ boson (d > 4)
The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
Compositeness
• Onion-like layers
• Composite fermions, scalars (dynamical sym. breaking)
• Not like to atom → nucleus +e− → p + n → quark
• Other new TeV layer: Little Higgs
• At most one more layer accessible (Tevatron, LHC, ILC)
• Rare decays (e.g., K → µe)
• Typically, few % effects at LEP/SLC, WNC (challenge for models)
• anomalous V V V , new particles, future WW → WW , FCNC,EDM
Yoichiro Nambu Symposium (April 21, 2005) Paul Langacker (Penn)
The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
Large extra dimensions (deconstruction, brane worlds)
• Can be motivated by strings, butnew dimensions much larger thanM−1
P ∼ 10−33 cm
• Fundamental scale MF ∼1 − 100 TeV # MP l =1/
√8πGN ∼ 2.4 × 1018 GeV
– Assume δ extra dimensionswith volume Vδ & M−δ
F
M2P l = M2+δ
F Vδ & M2F
(Introduces new hierarchy problem)
NYS APS (October 15, 2004) Paul Langacker (Penn)
The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
• Black holes, graviton emission atcolliders!
• Macroscopic gravity effects
• Astrophysics
NYS APS (October 15, 2004) Paul Langacker (Penn)
Particle Physics Probes Of Extra Spacetime Dimensions 29
Figure 7: 95% confidence level upper limits on the strength α (relative to Newtonian gravity)as a function of the range λ of additional Yukawa interactions. The region excluded by previousexperiments (55,56,61) lies above the curves labeled Irvine, Moscow and Lamoreaux, respectively.The most recent results (60) correspond to the curves labeled Eot-Wash. The heavy dashed line isthe result from Ref. (60), the heavy solid line shows the most recent analysis that uses the totaldata sample.
The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
Unification
• Unification of interactions
• Grand desert to unification (GUT) or Planck scale
• Elementary Higgs, supersymmetry (SUSY), GUTs, strings
• Possibility of probing to MP and very early universe
NYS APS (October 15, 2004) Paul Langacker (Penn)
The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
Supersymmetry
• Fermion ↔ boson symmetry
• Motivations
– stabilize weak scale ⇒ MSUSY < O(1 TeV) (but recent high scale
ideas)
– supergravity (gauged supersymmetry): unification of gravity(non-renormalizable)
– coupling constants in supersymmetric grand unification
– decoupling of heavy particles (precision)
Yoichiro Nambu Symposium (April 21, 2005) Paul Langacker (Penn)
The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
• Consequences
– additional charged and neutralHiggs particles
– M2H0 < cos2 2βM2
Z+ H.O.T.(O(m4
t)) < (150 GeV)2,consistent with LEP
∗ cf., standard model: MH0 <1000 GeV
NYS APS (October 15, 2004) Paul Langacker (Penn)
100 120 140 160 180 200mt [GeV]
10
20
50
100
200
500
1000
MH [
GeV
]
ΓZ, σhad, Rl, Rqasymmetriesν scatteringMWmt
excl
uded
all data90% CL
The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
• Superpartners
– q ⇒ q, scalar quark
– ! ⇒ !, scalar lepton
– W ⇒ w, wino
– typical scale: several hundredGeV
– LSP: cold dark mattercandidate
– SUSY breaking ⇔ large mt
– May be large FCNC, EDM,∆(gµ − 2)
NYS APS (October 15, 2004) Paul Langacker (Penn)
0
100
200
300
400
500
600
700
800
m [GeV]
lR
lLνl
τ1
τ2
χ0
1
χ0
2
χ0
3
χ0
4
χ±1
χ±2
uL, dRuR, dL
g
t1
t2
b1
b2
h0
H0, A0 H±
The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
Grand Unification
• Unify strong SU(3) andelectroweak SU(2)×U(1)in simple group, broken at∼ 1016 GeV
• Gauge unification (only insupersymmetric version)
NYS APS (October 15, 2004) Paul Langacker (Penn)
0
10
20
30
40
50
60
105
1010
1015
1 µ (GeV)
!i-1
(µ)
SMWorld Average!
1
!2
!3
!S(M
Z)=0.117±0.005
sin2"
MS__=0.2317±0.0004
0
10
20
30
40
50
60
105
1010
1015
1 µ (GeV)
!i-1
(µ)
MSSMWorld Average68%
CL
U.A.W.d.BH.F.
!1
!2
!3
The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
1636
mode exposure !Bm observed B.G. (ktï yr) (%) event
p " e+ + #
092 40 0 0.2 54
p " µ+ + #
092 32 0 0.2 43
p " e+ + $ 92 17 0 0.2 23
p " µ+ + $ 92 9 0 0.2 13
n " %__
+ $ 45 21 5 9 5.6p " e
+ + & 92 4.2 0 0.4 5.6
p " e+ + ' 92 2.9 0 0.5 3.8
p " e+ + ( 92 73 0 0.1 98
p " µ+ + ( 92 61 0 0.2 82
p " %__
+ K+
92 22K
+"%µ
+ (spectrum) 34 -- -- 4.2
prompt ( + µ+
8.6 0 0.7 11K
+"#
+#
0 6.0 0 0.6 7.9
n " %__
+ K0
92 2.0K
0"#
0#
0 6.9 14 19.2 3.0
K0"#
+#
- 5.5 20 11.2 0.8
p " e+ + K
092 10.7
K0"#
0#
0 9.2 1 1.1 8.7
K0"#
+#
-
2-ring 7.9 5 3.6 4.0 3-ring 1.3 0 0.1 1.7
p " µ+ + K
092 13.9
K0"#
0#
0 5.4 0 0.4 7.1
K0"#
+#
-
2-ring 7.0 3 3.2 4.9 3-ring 2.8 0 0.3 3.7
1031
1032
1033
1034
p " e+ #
0
e+ $
e+ '
e+ &
0
e+ K
0
µ+ #
0
µ+ $
µ+ '
µ+ &
0
µ+ K
0
%__
#+
%__
&+
%__
K+
n " e+ #
-
e+ &
-
µ+ #
-
µ+ &
-
%__
#0
%__
$%__
'%__
&0
%__
K0
lifetime limit (years)
KAMIMB3SK
Soudan2
Fig. 1. The obtained lifet ime limit of nucleons from SK–I (left figure) and their
comparisons with other experiments (right figure).
6. References
1. J. Ellis et al., Nucl. Phys. B202, 43 (1982)
2. Y.Fukuda et al., Phys. Rev. Let t . 81, 1562 (1998)
3. Y.Fukuda et al., Nucl. Instr. Meth. A501, 418 (2003)
4. H. Georgi and S. L. Glashow, Phys. Rev. Let t . 32, 438 (1974)
5. Y. Hayato et al., Phys. Rev. Let t . 83, 1529 (1999)
6. Jogesh C. Pat i and Abdus Salam, Phys. Rev. Let t . 31, 661 (1973)
7. For example, Jogesh C. Pat i, hep-ph/ 0005095.
8. N. Sakai and T. Yanagida, Nucl. Phys. B197, 533 (1982)
9. M. Shiozawa et al., Phys. Rev. Let t . 81, 3319 (1998)
10. M. Shiozawa, PhD thesis, University of Tokyo (1999)
11. S. Weinberg, Phys. Rev. D26, 287 (1982)
• Seesaw model for small mν (but
why are mixings large?)
• Quark-lepton (q − l) unification(⇒ charge quantization)
• q − l mass relations (work only for
third family in simplest versions)
• Proton decay? (simplest versions
excluded) Neutron oscillations?
• Doublet-triplet problem?
• String embedding? (breaking,
families may be entangled in extra
dimensions)
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
Superstrings
• Finite, “parameter-free” “theoryof everything” (TOE), includingquantum gravity
– 1-d string-like object
– Appears pointlike for resolution> M−1
P ∼ 10−33 cm
– Vibrational modes → particles
– Consistent in 10 space-time dimensions → 6 mustcompactify to scale M−1
P
– 4-dim supersymmetric gaugetheory below MP
– May also be solitons (branes),terminating open strings
NYS APS (October 15, 2004) Paul Langacker (Penn)
The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
• Problems
– Which compactification manifold?
– Supersymmetry breaking? Cosmological constant?
– Many moduli (vacua). Landscape ideas - is there anypredictability left?
– Relation to supersymmetric standard model, GUT?
• Need theoretical progress and hints from experiment
– TeV scale remnants, such as Z′, extended Higgs, exotics
– SUSY breaking patterns
– Need very precise masses and couplings →International LinearCollider
Yoichiro Nambu Symposium (April 21, 2005) Paul Langacker (Penn)
The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
Future/present Experiments
• High energy colliders: the primary tool
– TEVATRON; Fermilab, 1.96 TeV pp, exploration
– Large Hadron Collider (LHC); CERN, 14 TeV pp, high luminosity,discovery (Discovery machine for supersymmetry, Rp violation, string
remnants (e.g., Z′, exotics, Higgs); or compositeness, dynamical symmetry
breaking, Higgless theories, Little Higgs, large extra dimensions, · · ·)
– International Linear Collider (ILC), in planning;500 GeV-1 TeV e+e−, cold technology, high precision studies(Precision parameters to map back to string scale)
• CP violation (B decays, electric dipole moments), CKM universality,flavor changing neutral currents (e.g., µ→eγ, µN→eN, B→φKs),B violation (proton decay, n − n oscillations), neutrino physics
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
Neutrinos as a Unique Probe: 10−33 − 10+28 cm
• Particle Physics
– νN, µN, eN scattering: existence/ properties of quarks, QCD
– Weak decays (n → pe−νe, µ− → e−νµνe): Fermi theory, parityviolation, mixing
– Neutral current, Z-pole, atomic parity: electroweak unification,field theory, mt; severe constraint on physics to TeV scale
– Neutrino mass: constraint on TeV physics, grand unification,superstrings, extra dimensions; seesaw: mν ∼ m2
q/MGUT
Xalapa (August, 2004) Paul Langacker (Penn)
The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
• Solar/atmosphericneutrino experiments
– Neutrinos have tinymasses (but largemixings)
– Standard Solar modelconfirmed
– First oscillation dipsobserved! (QM onlarge scale)
NYS APS (October 15, 2004) Paul Langacker (Penn)
00.20.40.60.8
11.21.41.61.8
1 10 102 103 104 00.20.40.60.811.21.41.61.8
1 10 102 103 104
L/E (km/GeV)
Data
/Pre
dict
ion
(nul
l osc
.)
The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
3 ν Patterns
– Solar: LMA (SNO,KamLAND)
– ∆m2! ∼ 8×10−5 eV2,
nonmaximal
– Atmospheric:|∆m2
Atm| ∼ 2×10−3
eV2, near-maximal mixing
– Reactor: Ue3 small
The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
12
3
3
12
normal inverted
!
!
!"#$
νL
h
NR
v = 〈φ〉
mD = hv
Dirac
!
!
""##
##""
νL
νcR
$
!
""##
##""
νL
νL
Majorana
NYS APS (October 15, 2004) Paul Langacker (Penn)
Neutrino Implications/questions
• Key constituent of the Universe
• Why are the masses so small?
– Planck/GUT scale? e.g., seesawor generalization, mν ∼ m2
D/MN
(may not be generic in strings)
• Are the neutrinos Dirac orMajorana?
– No SM gauge symmetry forbidsMajorana (but string, extended?)
– Neutrinoless double beta decay(ββ0ν) (inverted or degeneratespectra)
Yoichiro Nambu Symposium (April 21, 2005) Paul Langacker (Penn)
The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
12
3
3
12
normal inverted
!
!
!"#$
νL
h
NR
v = 〈φ〉
mD = hv
Dirac
!
!
""##
##""
νL
νcR
$
!
""##
##""
νL
νL
Majorana
NYS APS (October 15, 2004) Paul Langacker (Penn)
degenerate
NYS APS (October 15, 2004) Paul Langacker (Penn)
• What is the spectrum: number,mass scale/pattern, mixings
– Scale: β decay (KATRIN), ββ0ν,large scale structure (SDSS)
– Mixings and CP: reactor, longbaseline oscillation experiments,Solar
– Pattern: long baseline, ββ0ν,supernova
– Number: LSND? MiniBooNE
• Leptogenesis?
• Relic neutrinos?
– Indirect: Nucleosynthesis, largescale structure. Direct? (Z-burst?)
Yoichiro Nambu Symposium (April 21, 2005) Paul Langacker (Penn)
The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
The Universe
• The concordance
– 5% matter (including darkbaryons): CMB, BBN, Lymanα
– 25% dark matter (galaxies,clusters, CMB, lensing)
– 70% dark energy (Acceleration(Supernovae), CMB (WMAP))
NYS APS (October 15, 2004) Paul Langacker (Penn)
The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
Perlmutter, Physics Today (2003)
Expansion History of the Universe
0.0
0.5
1.0
1.5
–20 –10 0
Billions Years from Today
10
0.05 today futurepast
Sca
le o
f the
Uni
vers
eR
elat
ive
to T
oday
's S
cale
After inflation,the expansion either...
collapsesexp
ands
forever
10.1
0.01
0.00
1
0.00
01relativebrightness
reds
hift
0
0.25
0.50.75
1
1.5
2.52
3
...or
alw
ays
dece
lera
ted
fir
st decelerated, th
en accelerated
• What is the dark matter?
– Lightest neutralino insupersymmetry (if R parityconserved)? Axion?
– Direct searches: LHC, ILC;cold dark matter searches; highenergy annihilation ν’s
– Gravitation lensing (SNAP),CMB (Planck)
• What is the dark energy?
– Vacuum energy (cosmological constant);time varying field (quintessence)?
– High precision supernova survey (SNAP);CMB (Planck)
NYS APS (October 15, 2004) Paul Langacker (Penn)
The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
101 10210−43
10−42
10−41
10−40
WIMP Mass [GeV]
Cros
s−se
ctio
n [c
m2 ] (
norm
alise
d to
nuc
leon
)• What is the dark matter?
– Lightest neutralino insupersymmetry (if R parityconserved)? Axion?
– Direct searches: LHC, ILC;cold dark matter searches; highenergy annihilation ν’s
– Axion searches (resonantcavities)
– Gravitation lensing (SNAP),CMB (Planck)
• What is the dark energy?
– Vacuum energy (cosmological constant);time varying field (quintessence)?
– High precision supernova survey (SNAP);CMB (Planck)
NYS APS (October 15, 2004) Paul Langacker (Penn)
The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
broken phase
becomes our world
unbroken phase
vWall
= 0φ
>> H
0CP CP_~ΓB + L
Sph
ΓB + L
Sph
q_q
_
q_q
_
• Why is there matter and notantimatter?
– nB/nγ ∼ 10−10, nB ∼ 0
– Electroweak baryogenesis(extensions of MSSM)? Leptogenesis?Decay of heavy fields? CPTviolation?
Yoichiro Nambu Symposium (April 21, 2005) Paul Langacker (Penn)
The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
• Why is there matter and notantimatter?
– nB/nγ ∼ 10−10, nB ∼ 0– Electroweak baryogenesis?
Leptogenesis? Decay of heavyfields? CPT violation?
• The very beginning (inflation)
– Relation to particle physics, strings, Λ?
– CMB (Planck); gravity waves (LISA)
NYS APS (October 15, 2004) Paul Langacker (Penn)
The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
Second extreme example: time varying couplings and parameters
(Murphy et al, astro-ph/0209488)
TASI (June 5, 2003) Paul Langacker (Penn)
Far-Out Stuff
• LIV, VEP (e.g., maximum speeds, decays, (oscillations) of HE γ, e, gravity
waves (ν’s))
• LED, TeV black holes
• Time varying couplings
Yoichiro Nambu Symposium (April 21, 2005) Paul Langacker (Penn)
The Standard Model and Beyond
TPFNP (October, 2005) Paul Langacker (FNAL/Penn/IAS)
Conclusions
• The standard model is the correct description of fermions/gaugebosons down to ∼ 10−16 cm ∼ 1
1 TeV
• EWSB: consistent with light elementary Higgs but not proved
• Standard model is complicated → must be new physics
• Precision tests severely constrain new TeV-scale physics
• Promising theoretical ideas at Planck scale
• Promising experimental program at colliders, accelerators, lowenergy, cosmology
• Challenge to make contact between theory and experiment
Yoichiro Nambu Symposium (April 21, 2005) Paul Langacker (Penn)