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Yang-Mills thermodynamics Ralf Hofmann Universit ¨ at Karlsruhe (TH) “Delta Meeting” ITP Heidelberg 2007 December 14, 2007 Yang-Mills thermodynamics – p.1/28

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Page 1: Yang-Mills thermodynamics - Heidelberg Universityhofmann/HD07.pdfat low temperature Yang-Mills thermodynamics – p.3/28. preview: phase diagram SU(2) (anti) screening confining preconfining

Yang-Mills thermodynamicsRalf Hofmann

Universitat Karlsruhe (TH)

“Delta Meeting”

ITP Heidelberg 2007

December 14, 2007

Yang-Mills thermodynamics – p.1/28

Page 2: Yang-Mills thermodynamics - Heidelberg Universityhofmann/HD07.pdfat low temperature Yang-Mills thermodynamics – p.3/28. preview: phase diagram SU(2) (anti) screening confining preconfining

planI brief motivation and preview on phase diagram

[hep-th/0504064 and 0710.0962]

I deconfining ground-state physics:coarse-grained, interacting calorons

I coarse-grained excitations:Legendre-trafos and loop expansion

I preconfinement:cond. magn. monopoles, dual Meissner effect

I low temperatures:Hagedorn, flip of statistics, Borel summation

I summary, conclusions, mention of applicationsYang-Mills thermodynamics – p.2/28

Page 3: Yang-Mills thermodynamics - Heidelberg Universityhofmann/HD07.pdfat low temperature Yang-Mills thermodynamics – p.3/28. preview: phase diagram SU(2) (anti) screening confining preconfining

Why nonpert. YMTD?I infrared instability of PT even for T � Λ

in magnetic sector[Linde 1980]

I highly nonpert. ground-state physics even for T � Λ:

– θµµ ∝ T , magnetic charge, ...[Miller 1998, Ilgenfritz et al., Muller-Preussker et al.,

Gattringer, Bruckmann & van Baal,

Garcia Perez et al., Bruckmann, Nogradi, van Baal...1999-2007]

– spatial string tension: σ ∝ T2

[Philipsen 1998, Korthals-Altes 1998, Laine et al. 2004 ...]

I limited lattice control of thermodynamical quantitiesat low temperature Yang-Mills thermodynamics – p.3/28

Page 4: Yang-Mills thermodynamics - Heidelberg Universityhofmann/HD07.pdfat low temperature Yang-Mills thermodynamics – p.3/28. preview: phase diagram SU(2) (anti) screening confining preconfining

preview: phase diagram SU(2)

� �� �� ����

confining preconfining

ground state:

condensate of magnetic monopoles, collapsing center−vortex loops,negative pressure

excitations: massless and massive gauge modes

ground state: interacting calorons and anticalorons, negative pressure

power−like approach to Stefan Boltzmann limit

deconfining

2nd order likeHagedorn

excitations:

massive dual gauge modes

Cooper−pair condensateof single center−

ground state:

vortex loops, pressureprecisely zero

excitations:

massless (single) and massive (self−intersecting) center−vortex loops (spin−1/2 fermions)

T

P/T4 T 4ρ/ T 4

12 14 16 18 20 22 24

-2.5

-2

-1.5

-1

-0.5

0

0.5

1

12 14 16 18 20 22 24

1.8

2

2.2

2.4

2.6

electr

ic

mag

netic

electr

ic

mag

netic

Stefan−Boltzmann limit Stefan−Boltzmann limit

ρ/Τ =as 2.62P/T4as = 0.86

ρc,M /T

4c,E

ρ /T4c,Ec,E

λE

Tc

γV

+, V

(anti) screening

−+

c =2.73 KTdecoupling of , VV

−4, no (anti) screening

Λ∼10 eV

Yang-Mills thermodynamics – p.4/28

Page 5: Yang-Mills thermodynamics - Heidelberg Universityhofmann/HD07.pdfat low temperature Yang-Mills thermodynamics – p.3/28. preview: phase diagram SU(2) (anti) screening confining preconfining

deconfining ground stateI coarse-grained (anti)calorons of |Q| = 1

⇒ adjoint scalar field φa, |φ| spatially homogeneous

I strategy:

– thermodynamics ⇒ φa periodic in eucl. timein any admissible gauge ⇒phase φa determined by classical configs.

– stable configs.: |Q| = 1 HS (anti)calorons (BPS)of trivial holonomy

(no EXPLICIT holonomy in deconfining phase!)[Gross, Pisarski, Yaffe 1981]

Yang-Mills thermodynamics – p.5/28

Page 6: Yang-Mills thermodynamics - Heidelberg Universityhofmann/HD07.pdfat low temperature Yang-Mills thermodynamics – p.3/28. preview: phase diagram SU(2) (anti) screening confining preconfining

– compute φa ∈(Kernel of D)≡ K respectingisotropy and SHS = 8π2

g2 6= f(T, Λ) ininf.-vol. average over magnetic-magneticcorrelation mediated by single (anti)caloron

– fixes D uniquely ⇒ winding number

– pick max. resolution µ such that µ = |φ| = const

– consistency of BPS and Euler-Lagrange

⇒ V (φ) and Λ as constant of integration

⇒ µ = |φ| consistent with IR saturation of K

Yang-Mills thermodynamics – p.6/28

Page 7: Yang-Mills thermodynamics - Heidelberg Universityhofmann/HD07.pdfat low temperature Yang-Mills thermodynamics – p.3/28. preview: phase diagram SU(2) (anti) screening confining preconfining

technically:

(integration over SR=∞3 )

φa(τ) ∈∑

HS (anti)caloron

tr∫

d3x

dρλa

Fµν ((τ, 0)) {(τ, 0), (τ, ~x)} ×

Fµν ((τ, ~x)) {(τ, ~x), (τ, 0)} .

Fµν (x) Fµν (x)

Fµν (0)µν (0)Fz0 z

or

Fµν(z) 0

a parallel transport into isotropic case or gauge trafo thereof

isotropic case other path prohibited by isotropy since not

Yang-Mills thermodynamics – p.7/28

Page 8: Yang-Mills thermodynamics - Heidelberg Universityhofmann/HD07.pdfat low temperature Yang-Mills thermodynamics – p.3/28. preview: phase diagram SU(2) (anti) screening confining preconfining

saturation:

0 0.5 1 1.5 2

-300

-200

-100

0

100

200

300

0 0.5 1 1.5 2

-2000

-1000

0

1000

2000

0 0.5 1 1.5 2

-200000

-100000

0

100000

200000

(2π/β) τ

A ζ=10ζ=1 ζ=2

Yang-Mills thermodynamics – p.8/28

Page 9: Yang-Mills thermodynamics - Heidelberg Universityhofmann/HD07.pdfat low temperature Yang-Mills thermodynamics – p.3/28. preview: phase diagram SU(2) (anti) screening confining preconfining

=⇒

D = ∂2τ +

(

2πβ

)2

⇒ ∂|φ|2V (|φ|2) = −V (|φ|2)|φ|2 ⇒ V (φ) = tr Λ6φ−2

⇒ |φ| =√

Λ3

2π T

⇒ unique, coarse-grained action fornoninteracting |Q| = 1 HS (anti)calorons

⇒ φ’s inertness for λ ≡ 2πTΛ ≥ 13.87 = λc

(as we shall see)

Yang-Mills thermodynamics – p.9/28

Page 10: Yang-Mills thermodynamics - Heidelberg Universityhofmann/HD07.pdfat low temperature Yang-Mills thermodynamics – p.3/28. preview: phase diagram SU(2) (anti) screening confining preconfining

What about Q = 0?I perturbative renormalizability:

[’t Hooft, Veltman 1971-73]

⇒ coarse-graining over Q = 0 yieldssame form as fundamental action

I gauge invariance glues Q = 0 to |Q| = 1 ⇒

S = tr∫ β

0 dτ∫

d3x(

12GµνGµν + DµφDµφ + Λ6φ−2

)

I subject to offshellness constraints inunitary-Coulomb gauge(coarse-graining down to resolution |φ|)

Yang-Mills thermodynamics – p.10/28

Page 11: Yang-Mills thermodynamics - Heidelberg Universityhofmann/HD07.pdfat low temperature Yang-Mills thermodynamics – p.3/28. preview: phase diagram SU(2) (anti) screening confining preconfining

full ground stateI from DµGµν = ie[φ,Dνφ]:

– pure gauge abgµ = π

eTδµ4 λ3

⇒ ground-state energy-density and pressure

ρg.s = 4π Λ3 T = −P g.s 6= 0

I rotation to unitary gauge abgµ = 0:

– gauge transformation singular but admissible

(does not affect periodicity of fluct. δaµ)

– but: Pol[abg] = −1GT→ Pol[abg] = +1

⇒ Zel2 degeneracy

⇒ deconfinement

Yang-Mills thermodynamics – p.11/28

Page 12: Yang-Mills thermodynamics - Heidelberg Universityhofmann/HD07.pdfat low temperature Yang-Mills thermodynamics – p.3/28. preview: phase diagram SU(2) (anti) screening confining preconfining

excitations and loop expansionI adjoint Higgs mechanism:

2 out of 3 directions massive with m = e

Λ3

E

2πT

I evol. of eff. coupl. e: Legendre trafos betw. P , ρ, ...⇒ e =

√8π almost everywhere

λc12 14 16 18 20

5

10

15

20

25

λE

g e

elec

tric

mag

netic

= 4 π /e

plateau: e=8 1/2 π

=2 π T/ Λ

− )λ λce~−log(

Yang-Mills thermodynamics – p.12/28

Page 13: Yang-Mills thermodynamics - Heidelberg Universityhofmann/HD07.pdfat low temperature Yang-Mills thermodynamics – p.3/28. preview: phase diagram SU(2) (anti) screening confining preconfining

I trace anomaly: θµµ

Λ4 = 12λ for λ � λc

[Giacosa, RH 2007]

I counting of d.o.f.:

fundamentally:3 species (gluons)×2 pols.+1 species (monop)×2 charges =8

after coarse-graining:2 species (gluons)×3 pols.+1 species (gluon)×2 pols.=8

⇒ 8 (fund)=8 (coarse-grained).

same way for SU(3):⇒ 22 (fund)=22 (coarse-grained)

Yang-Mills thermodynamics – p.13/28

Page 14: Yang-Mills thermodynamics - Heidelberg Universityhofmann/HD07.pdfat low temperature Yang-Mills thermodynamics – p.3/28. preview: phase diagram SU(2) (anti) screening confining preconfining

I loop expansion:2-loop:[Rohrer,Herbst,RH 2004; Schwarz,RH,Giacosa 2006]

∆P =1

4+

1

8

+

0 20 40 60 80-0.0035

-0.003

-0.0025

-0.002

-0.0015

-0.001

-0.0005

0

HHM + ∆ Pttv ∆ P HHMttc( )/P1−loop

λ

Yang-Mills thermodynamics – p.14/28

Page 15: Yang-Mills thermodynamics - Heidelberg Universityhofmann/HD07.pdfat low temperature Yang-Mills thermodynamics – p.3/28. preview: phase diagram SU(2) (anti) screening confining preconfining

irreducible 3-loop:[Kaviani,RH 2007]

+ +481

1 2

3 4

5

34213 1 2 4

p4= p p p1+ _

2 3 p4= p p p1+ _

2 3p4= p p p1+ _

2 3p = p5 1

p_3

A B C

20 40 60 80 100 120 140

5·10-8

1·10-7

1.5·10-7

2·10-7

λ

P|∆ 1−loop| /P> B

Yang-Mills thermodynamics – p.15/28

Page 16: Yang-Mills thermodynamics - Heidelberg Universityhofmann/HD07.pdfat low temperature Yang-Mills thermodynamics – p.3/28. preview: phase diagram SU(2) (anti) screening confining preconfining

arguments on loop expansion in general:[RH 2006]

– resummation of 1PI diagrams⇒ no pinch singularities

– irreducible diagrams terminateat finite loop order

(Euler characteristics for spherical polyhedron,constraints on loop momenta in effective theory⇒number of constraints exceedsnumber of independent radial loop variables

at sufficiently large number of loops)Yang-Mills thermodynamics – p.16/28

Page 17: Yang-Mills thermodynamics - Heidelberg Universityhofmann/HD07.pdfat low temperature Yang-Mills thermodynamics – p.3/28. preview: phase diagram SU(2) (anti) screening confining preconfining

preconfining phaseI cond. of monop. (stable, nontrivial holonomy):

[Diakonov et al. 2004; Gerhold, Ilgenfritz, Muller-Preussker2006; Diakonov & Petrov 2007]

– phase of complex scalar =magnetic flux through SR=∞

2of M-A pair at rest (e → ∞)

– modulus as in dec. phase– no change of form of action for

free dual gauge modes by coarse-graining⇒ unique effective action– Polyakov loop always unique– pressure exact at one loop– evol. of dual coupling g (Legendre trafos)

Yang-Mills thermodynamics – p.17/28

Page 18: Yang-Mills thermodynamics - Heidelberg Universityhofmann/HD07.pdfat low temperature Yang-Mills thermodynamics – p.3/28. preview: phase diagram SU(2) (anti) screening confining preconfining

I counting of d.o.f.:

fundamentally:

1 species (’photon’)×2 pols.+1 species (center-vortex loop) =3

after coarse-graining:

1 species (massive ’photon’)×3 pols.=3

⇒ 3 (fund)=3 (coarse-grained).

same way for SU(3):⇒ 6 (fund)=6 (coarse-grained)

Yang-Mills thermodynamics – p.18/28

Page 19: Yang-Mills thermodynamics - Heidelberg Universityhofmann/HD07.pdfat low temperature Yang-Mills thermodynamics – p.3/28. preview: phase diagram SU(2) (anti) screening confining preconfining

low temperatureI condensation of center-vortex loops (CVL’s)

[’t Hooft 1978, de Forcrand & Smekal 2002, de Forcrand & Noth2005, ... ]

– discrete values of phase of complex scalar field= units of center flux through min. surface;spanned by SR=∞

1 ; modulus=condensate– spectrum: single and selfintersecting CVL’s

n=2:

n=3:= 4

)

)

2

3

= )1n= 0:

0

n=1: = )11

(

(N

(N2=

N

(N4λφ

multiplicity of mass−n soliton: number of connected bubble diagrams at order n in

large−order counting:

[Bender, Wu 1969−76]anharmonic oscillator

over−exponentially in energy growing density of states

Hagedorn transition topreconfining phase

Yang-Mills thermodynamics – p.19/28

Page 20: Yang-Mills thermodynamics - Heidelberg Universityhofmann/HD07.pdfat low temperature Yang-Mills thermodynamics – p.3/28. preview: phase diagram SU(2) (anti) screening confining preconfining

I counting of d.o.f.:

fundamentally:

1 species (’very massive photon’)×3 pols.=3

after coarse-graining:

1 species (massless CVL)+1 species (massive CVL)× 2 charges=3

⇒ 3 (fund)=3 (coarse-grained).

same way for SU(3):

⇒ 6 (fund)=6 (coarse-grained)

Yang-Mills thermodynamics – p.20/28

Page 21: Yang-Mills thermodynamics - Heidelberg Universityhofmann/HD07.pdfat low temperature Yang-Mills thermodynamics – p.3/28. preview: phase diagram SU(2) (anti) screening confining preconfining

– potential unique up to inessential,U(1) invariant rescaling[lattice invest.: Scheffler, RH, Stamatescu 2007]

-1

0

1-1

0

1

0

2

4

-1

0

1

-1

0

1-1

0

1

02468

-1

0

1

SU(2) SU(3)

pole

zero

negative tangential curvature

negative tangential curvature

negative tangential curvature

negative tangential curvaturenega

tive t

ange

ntia

l cur

vatu

re

Yang-Mills thermodynamics – p.21/28

Page 22: Yang-Mills thermodynamics - Heidelberg Universityhofmann/HD07.pdfat low temperature Yang-Mills thermodynamics – p.3/28. preview: phase diagram SU(2) (anti) screening confining preconfining

– asymptotic-series representation of pressure:

Pas = Λ4

2π2 β−4×

(

7π4

180 +√

2π β3

2

∑Ll=0 al

n≥1(32λ)n n! n3

2+l

)

,

where β ≡ Λ/T and λ ≡ exp[−β].[uses Bender, Wu 1968–1976]

– Borel transformation and analytic continuation⇒ analytic dependence on Borel parameter t(polylogs) for λ < 0

– inverse Borel trafo:⇒ analytic dependence for λ < 0 and

meromorphic in entire λ-plane except for λ ≥ 0Yang-Mills thermodynamics – p.22/28

Page 23: Yang-Mills thermodynamics - Heidelberg Universityhofmann/HD07.pdfat low temperature Yang-Mills thermodynamics – p.3/28. preview: phase diagram SU(2) (anti) screening confining preconfining

analyticity structure of physical pressure P :

Im λ

Re λP analytic branch cut

isolated poles

λ = e−T/Λ

Yang-Mills thermodynamics – p.23/28

Page 24: Yang-Mills thermodynamics - Heidelberg Universityhofmann/HD07.pdfat low temperature Yang-Mills thermodynamics – p.3/28. preview: phase diagram SU(2) (anti) screening confining preconfining

– Re P continuous across cut:– sign-ambiguous Im P grows slower than Re P

– turbulences become relevant for sufficiently high T only

0 0.05 0.1 0.15 0.2 0.25 0.3

-0.07

-0.06

-0.05

-0.04

-0.03

-0.02

-0.01

0

0 0.002 0.004 0.006 0.008 0.01-0.01

-0.008

-0.006

-0.004

-0.002

0

0 0.05 0.1 0.15 0.20

0.0025

0.005

0.0075

0.01

0.0125

0.015

0.0175

0 0.2 0.4 0.6 0.8 1

-0.05

-0.04

-0.03

-0.02

-0.01

0

0 0.00020.00040.00060.0008 0.0010

0.001

0.002

0.003

0.004

(a) (b)

(c) (d)

(e) Yang-Mills thermodynamics – p.24/28

Page 25: Yang-Mills thermodynamics - Heidelberg Universityhofmann/HD07.pdfat low temperature Yang-Mills thermodynamics – p.3/28. preview: phase diagram SU(2) (anti) screening confining preconfining

summary and conclusionsI deconf. phase:

– magnetic-magnetic correlations in(anti)calorons generate adj. Higgs field

– rapid saturation of average

– negative ground-state pressure by microscopicholonomy shifts (annihilating M-A pairs)

– thermal quasiparticles on tree level(adj. Higgs mech.)

– very small radiative corrections, terminationof expansion in terms of irreducible loops

Yang-Mills thermodynamics – p.25/28

Page 26: Yang-Mills thermodynamics - Heidelberg Universityhofmann/HD07.pdfat low temperature Yang-Mills thermodynamics – p.3/28. preview: phase diagram SU(2) (anti) screening confining preconfining

I preconf. phase:

– averaged magnetic flux of M-A pairthrough S∞

2 generates phaseof complex scalar

– dual gauge field Meissner massive

– loop expansion trivial

Yang-Mills thermodynamics – p.26/28

Page 27: Yang-Mills thermodynamics - Heidelberg Universityhofmann/HD07.pdfat low temperature Yang-Mills thermodynamics – p.3/28. preview: phase diagram SU(2) (anti) screening confining preconfining

I conf. phase:– averaged center flux of CVL pair

through min. surface spanned by S∞1

generates discrete values of phaseof complex scalar; modulus=condensate

– excitations are single or selfintersecting CVL’sof factorially growing multiplicity

– asymptotic-series representation of pressure– Borel summability for complex values of T– analytic continuation: rapidly (slowly) rising

modulus of real (imaginary) part– interpretation: growing relevance of turbulences

with increasing T

Yang-Mills thermodynamics – p.27/28

Page 28: Yang-Mills thermodynamics - Heidelberg Universityhofmann/HD07.pdfat low temperature Yang-Mills thermodynamics – p.3/28. preview: phase diagram SU(2) (anti) screening confining preconfining

I physics applications:

– CMB

– late-time cosmology (axion + SU(2))

– electroweak symmetry breaking

Thank you.

Yang-Mills thermodynamics – p.28/28