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t Hooft limit (1, 2, 3, ···∞) - Theoretical Physics (TIFR)

t Hooft limit (1, 2, 3, ···∞) - Theoretical Physics (TIFR)

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Outline T c<br />

Latent heat EOS Summary<br />

The gluoN c plasma and its ’t <strong>Hooft</strong> <strong>limit</strong><br />

(1, 2, 3, · · · ∞)<br />

Saumen Datta and Sourendu Gupta<br />

ILGTI: <strong>TIFR</strong><br />

Extreme QCD 2010<br />

Physikzentrum Bad Honnef, Germany<br />

June 21, 2010<br />

SG<br />

Large N c Thermodynamics


Outline T c<br />

Latent heat EOS Summary<br />

RG scaling and ’t <strong>Hooft</strong> scaling<br />

Latent heat<br />

Equation of state<br />

Summary<br />

SG<br />

Large N c Thermodynamics


Outline T c<br />

Latent heat EOS Summary<br />

Limiting procedures<br />

◮ ’t <strong>Hooft</strong> scaling <strong>limit</strong>: take N c → ∞ and g 2 → 0 keeping<br />

λ = g 2 N c fixed. Correlation functions can be computed<br />

non-perturbatively but diagrammatically by resumming a<br />

well-defined class of diagrams. Simple caricature of hadron<br />

physics in this <strong>limit</strong>.<br />

’t <strong>Hooft</strong>, Coleman; tested by Teper and collaborators<br />

Extended to many other classes of theories. AdS/CFT<br />

correspondence works in the ’t <strong>Hooft</strong> <strong>limit</strong> of N c → ∞.<br />

◮ Strong scaling <strong>limit</strong>: work at (fixed) long distance scales and<br />

take N c → ∞. Non-perturbative content of the theory may be<br />

explored on the lattice and the <strong>limit</strong> taken.<br />

Teper, Lucini and collaborators<br />

Corrections organized in power of 1/N c<br />

SG<br />

Large N c Thermodynamics


Outline T c Latent heat EOS Summary<br />

Flag diagram of gluoN c plasmas<br />

line of chiral transitions<br />

0<br />

m<br />

N c<br />

3<br />

2+ε<br />

SG<br />

Large N c Thermodynamics


Outline T c Latent heat EOS Summary<br />

Flag diagram of gluoN c plasmas<br />

line of chiral transitions<br />

N c<br />

3<br />

0<br />

~10 MeV<br />

m<br />

2+ε<br />

SG<br />

Large N c Thermodynamics


Outline T c Latent heat EOS Summary<br />

Flag diagram of gluoN c plasmas<br />

line of chiral transitions<br />

0<br />

m<br />

Τ<br />

Deconfined<br />

Baryonic<br />

Α<br />

Quarkyonic<br />

µ<br />

N c<br />

3<br />

2+ε<br />

SG<br />

Large N c Thermodynamics


Outline T c Latent heat EOS Summary<br />

Flag diagram of gluoN c plasmas<br />

line of chiral transitions<br />

Τ<br />

Baryonic<br />

Deconfined<br />

Quarkyonic?<br />

µ<br />

N c<br />

Β<br />

3<br />

0<br />

m<br />

2+ε<br />

SG<br />

Large N c Thermodynamics


Outline<br />

Outline T c<br />

Latent heat EOS Summary<br />

RG scaling and ’t <strong>Hooft</strong> scaling<br />

Latent heat<br />

Equation of state<br />

Summary<br />

SG<br />

Large N c Thermodynamics


Outline T c Latent heat EOS Summary<br />

Unphysical strong–weak coupling crossover<br />

0.65<br />

0.60<br />

<br />

0.55<br />

0.50<br />

0.45<br />

0.40<br />

8 terms<br />

7 terms<br />

0.35<br />

0.30<br />

0.25<br />

8 9 10 11 12<br />

β<br />

Wilson action. Earlier generation of simulations <strong>limit</strong>ed by this<br />

bulk transition; solution now: move to smaller lattice spacing.<br />

Teper and collaborators, Panero<br />

SG<br />

Large N c Thermodynamics


Outline T c<br />

Latent heat EOS Summary<br />

· · · no longer a problem<br />

0.6<br />

SU(4)<br />

<br />

0.55<br />

N s =18<br />

N<br />

0.5<br />

s =24<br />

10.4 10.6 10.8 11 11.2 11.4<br />

Clear 1st order transition signal in L but not in plaquette: therefore<br />

thermal transition, not bulk. Similarly for N c = 6, 8 and 10.<br />

Computations for N t = 6, 8, 10 and (sometimes) 12.<br />

SG<br />

β<br />

Large N c Thermodynamics


Outline T c<br />

Latent heat EOS Summary<br />

· · · no longer a problem<br />

0.12<br />

SU(4)<br />

<br />

0.08<br />

0.04<br />

N s =18<br />

N<br />

0<br />

s =24<br />

10.4 10.6 10.8 11 11.2 11.4<br />

Clear 1st order transition signal in L but not in plaquette: therefore<br />

thermal transition, not bulk. Similarly for N c = 6, 8 and 10.<br />

Computations for N t = 6, 8, 10 and (sometimes) 12.<br />

SG<br />

β<br />

Large N c Thermodynamics


Outline T c Latent heat EOS Summary<br />

· · · no longer a problem<br />

0.08<br />

SU(4),β=10.79<br />

0.04<br />

N s =22<br />

Im L<br />

0<br />

-0.04<br />

-0.08<br />

-0.08 -0.04 0 0.04 0.08<br />

Re L<br />

Clear 1st order transition signal in L but not in plaquette: therefore<br />

thermal transition, not bulk. Similarly for N c = 6, 8 and 10.<br />

Computations for N t = 6, 8, 10 and (sometimes) 12.<br />

SG<br />

Large N c Thermodynamics


Outline T c Latent heat EOS Summary<br />

Precision test of RG<br />

Nt<br />

10<br />

Τ<br />

c<br />

8<br />

Τ<br />

c<br />

6<br />

Τ<br />

c<br />

β 10.788 11.078 11.339<br />

β c determined to one part in 10 4 . Strong coupling determined<br />

non-perturbatively. 2-loop RG works with precision of two parts in<br />

10 3 for a ≤ 1/(8T c ). For larger a: non-perturbative RG.<br />

SG<br />

Large N c Thermodynamics


Outline T c Latent heat EOS Summary<br />

Precision test of RG<br />

Nt<br />

10<br />

8<br />

(4/5)<br />

Τ c<br />

Τ<br />

c<br />

Τ<br />

c<br />

6<br />

Τ<br />

c<br />

(4/3) Τ<br />

c<br />

β 10.788 11.078 11.339<br />

β c determined to one part in 10 4 . Strong coupling determined<br />

non-perturbatively. 2-loop RG works with precision of two parts in<br />

10 3 for a ≤ 1/(8T c ). For larger a: non-perturbative RG.<br />

SG<br />

Large N c Thermodynamics


Outline T c Latent heat EOS Summary<br />

Precision test of RG<br />

Nt<br />

10<br />

(4/5)<br />

Τ c<br />

0.804(3)<br />

Τ<br />

c<br />

8<br />

Τ<br />

c<br />

6<br />

Τ<br />

c<br />

(4/3) Τ<br />

c<br />

1.308 (2)<br />

β 10.788 11.078 11.339<br />

β c determined to one part in 10 4 . Strong coupling determined<br />

non-perturbatively. 2-loop RG works with precision of two parts in<br />

10 3 for a ≤ 1/(8T c ). For larger a: non-perturbative RG.<br />

SG<br />

Large N c Thermodynamics


Outline T c<br />

Latent heat EOS Summary<br />

Precision test of RG<br />

2.5<br />

SU(4)<br />

T/T c (N t =6)<br />

2<br />

1.5<br />

1<br />

N t =5<br />

N t =6<br />

N t =8<br />

N t =10<br />

10.8 11 11.2 11.4 11.6 11.8<br />

β c determined to one part in 10 4 . Strong coupling determined<br />

non-perturbatively. 2-loop RG works with precision of two parts in<br />

10 3 for a ≤ 1/(8T c ). For larger a: non-perturbative RG.<br />

SG<br />

β<br />

Large N c Thermodynamics


Outline T c<br />

Latent heat EOS Summary<br />

Precision test of RG<br />

4<br />

3<br />

SU(4)<br />

T/T c (N t =6)<br />

2<br />

1<br />

N t =5<br />

N t =6<br />

N t =8<br />

N t =10<br />

10.4 11 11.6 12.2<br />

β c determined to one part in 10 4 . Strong coupling determined<br />

non-perturbatively. 2-loop RG works with precision of two parts in<br />

10 3 for a ≤ 1/(8T c ). For larger a: non-perturbative RG.<br />

SG<br />

β<br />

Large N c Thermodynamics


Outline T c<br />

Latent heat EOS Summary<br />

Step-scaling functions<br />

0.6<br />

∆β=β(a)-β(2a)<br />

0.5<br />

0.4<br />

V-scheme<br />

E-scheme<br />

Nonperturbative<br />

Boyd et al<br />

SU(3)<br />

0.3<br />

6 6.5 7<br />

β(a)<br />

SG<br />

Large N c Thermodynamics


Outline T c Latent heat EOS Summary<br />

Step-scaling functions<br />

1<br />

V-scheme<br />

E-scheme<br />

∆β=β(a)-β(2a)<br />

0.6<br />

Nonperturbative<br />

0.2<br />

SU(4)<br />

10.6 11 11.4 11.8 12.2<br />

β(a)<br />

SG<br />

Large N c Thermodynamics


Outline T c Latent heat EOS Summary<br />

’t <strong>Hooft</strong> scaling: fixed λ, fixed physics<br />

10.5<br />

10<br />

λ c (2πT c )<br />

9.5<br />

9<br />

8.5<br />

8<br />

0 0.04 0.08 0.12<br />

2<br />

1/N c<br />

λ c = g 2 (T c )N c . Clearly non-linear (even ignoring N t = 8 and 10).<br />

SG<br />

Large N c Thermodynamics


Outline T c Latent heat EOS Summary<br />

Very large corrections<br />

Best-fit function:<br />

λ c =<br />

{<br />

9.8771(4) −<br />

14.2562(2)<br />

N 2 c<br />

9.9904(6) + 1.2081(3)<br />

N 2 c<br />

+ 54.7830(2)<br />

N 4 c<br />

− 23.5709(3)<br />

N 4 c<br />

(non-perturbative),<br />

(2-loop).<br />

SG<br />

Large N c Thermodynamics


Outline T c Latent heat EOS Summary<br />

Very large corrections<br />

Best-fit function:<br />

λ c =<br />

{<br />

9.8771(4) −<br />

14.2562(2)<br />

N 2 c<br />

9.9904(6) + 1.2081(3)<br />

N 2 c<br />

+ 54.7830(2)<br />

N 4 c<br />

− 23.5709(3)<br />

N 4 c<br />

(non-perturbative),<br />

(2-loop).<br />

For N c = 3<br />

λ c =<br />

{<br />

9.8771(4) − 1.584 + 0.676 (non-perturbative),<br />

9.9904(6) + 0.134 − 0.291 (2-loop).<br />

1/N 2 c and 1/N 4 c corrections nearly equal to each other.<br />

SG<br />

Large N c Thermodynamics


Outline<br />

Outline T c<br />

Latent heat EOS Summary<br />

RG scaling and ’t <strong>Hooft</strong> scaling<br />

Latent heat<br />

Equation of state<br />

Summary<br />

SG<br />

Large N c Thermodynamics


Outline T c<br />

Latent heat EOS Summary<br />

Multiple peaks?<br />

50<br />

SU(4), N t =6, β=10.79<br />

40<br />

Prob(|L|)<br />

30<br />

20<br />

10<br />

N s =16<br />

0<br />

N s =24<br />

0 0.02 0.04 0.06 0.08<br />

|L|<br />

Clear multiple peaks for L but not for plaquette. Entropy surface<br />

not flat? Not a true first order transition?<br />

SG<br />

Large N c Thermodynamics


Outline T c Latent heat EOS Summary<br />

Multiple peaks?<br />

800<br />

700<br />

600<br />

SU(4), N t =6<br />

β=10.79<br />

N s =24<br />

Prob(δP)<br />

500<br />

400<br />

300<br />

200<br />

100<br />

N s =16<br />

0<br />

-0.002 -0.001 0 0.001 0.002 0.003<br />

δP<br />

Clear multiple peaks for L but not for plaquette. Entropy surface<br />

not flat? Not a true first order transition?<br />

SG<br />

Large N c Thermodynamics


Outline T c Latent heat EOS Summary<br />

Isolate phases using order parameter<br />

800<br />

β=10.78<br />

800<br />

β=10.78<br />

600<br />

Low<br />

High<br />

600<br />

Low<br />

High<br />

Prob(δP)<br />

Prob(δP)<br />

Prob(δP)<br />

400<br />

200<br />

8000<br />

600<br />

400<br />

200<br />

8000<br />

600<br />

400<br />

200<br />

Low<br />

Low<br />

β=10.79<br />

High<br />

β=10.80<br />

High<br />

Prob(δP)<br />

Prob(δP)<br />

Prob(δP)<br />

400<br />

200<br />

8000<br />

600<br />

400<br />

200<br />

8000<br />

600<br />

400<br />

200<br />

Low<br />

Low<br />

β=10.79<br />

High<br />

β=10.80<br />

High<br />

Stable against change in V and a<br />

0<br />

-0.002 -0.001 0 0.001 0.002 0.003<br />

0<br />

-0.002 -0.001 0 0.001 0.002 0.003<br />

δP<br />

δP<br />

SG<br />

Large N c Thermodynamics


Outline T c Latent heat EOS Summary<br />

Is N c = 3 special?<br />

N t N s ∆E/Tc 4 ∆E/∆ max<br />

4 16 2.06(1)(3)<br />

24 1.93(1)(3)<br />

32 1.90(2)(2)<br />

6 16 1.79(2)(4) 0.65(2)<br />

32 1.54(2)(5)<br />

48 1.44(4)(3)<br />

N c ≥ 4 results stable for N s /N t ≃ 3. But large finite size effect for<br />

N c = 3.<br />

SG<br />

Large N c Thermodynamics


Outline T c<br />

Latent heat EOS Summary<br />

Scaling with N c<br />

Latent heat depends on N c even after scaling by number of gluons:<br />

T A = N 2 c − 1. Best fit result—<br />

∆ǫ<br />

T A T 4 c<br />

= 0.388(3) − 1.61(4)<br />

Nc<br />

2 .<br />

N c = 3 may have larger finite volume effects than larger N c .<br />

For N c = 2<br />

∆ǫ<br />

T A Tc<br />

4 = 0.388(3) − 0.40(1) = 0!<br />

Good news? Bad news?<br />

SG<br />

Large N c Thermodynamics


Outline<br />

Outline T c<br />

Latent heat EOS Summary<br />

RG scaling and ’t <strong>Hooft</strong> scaling<br />

Latent heat<br />

Equation of state<br />

Summary<br />

SG<br />

Large N c Thermodynamics


Outline T c Latent heat EOS Summary<br />

Conformal symmetry breaking<br />

0.4<br />

SU(3)<br />

SU(4)<br />

SU(6)<br />

∆/(T A T 4 )<br />

0.2<br />

0<br />

1 2 3 4<br />

T/T c<br />

Good scaling of ∆/T 4 = (E − 3P)/T 4 with N c at fixed T/T c<br />

(strong N c scaling).<br />

∆ 1/4 ≃ T even at T ≃ 2T c for N c = 3: conformal symmetry<br />

broken. SG Large N c Thermodynamics


Outline T c Latent heat EOS Summary<br />

Evidence for mass?<br />

0.4<br />

∆/(T A T 2 T c<br />

2 )<br />

0.2<br />

0<br />

SU(3)<br />

SU(4)<br />

SU(6)<br />

1 2 3 4<br />

T/T c<br />

∆/T 2 ≃ constant is generic evidence for mass scales persisting in<br />

the high temperature phase.<br />

Meisinger, Miller, Ogilvie, 2002; Pisarski, 2007<br />

SG<br />

Large N c Thermodynamics


Outline T c<br />

Latent heat EOS Summary<br />

Cutoff dependence of pressure<br />

1<br />

0.8<br />

SU(4)<br />

p/p SB<br />

0.6<br />

0.4<br />

0.2<br />

0<br />

N t =5(Panero)<br />

N t =6<br />

N t =8<br />

1 2 3 4<br />

T/T c<br />

SG<br />

Large N c Thermodynamics


Outline T c<br />

Main results<br />

Latent heat EOS Summary<br />

4<br />

SU(4)<br />

Ts/p SB<br />

3<br />

ε/p SB<br />

2<br />

1<br />

p/p SB<br />

0<br />

1 2 3 4<br />

T/T c<br />

Far from ideal gas.<br />

Good scaling of EOS with N c at fixed T/T c (strong N c scaling).<br />

SG<br />

Large N c Thermodynamics


Outline T c<br />

Main results<br />

Latent heat EOS Summary<br />

1<br />

0.8<br />

0.2<br />

0<br />

ε/ε SB<br />

p/p SB<br />

SU(3)<br />

SU(4)<br />

SU(6)<br />

1 2 3 4<br />

T/T c<br />

0.6<br />

0.4<br />

Far from ideal gas.<br />

Good scaling of EOS with N c at fixed T/T c (strong N c scaling).<br />

SG<br />

Large N c Thermodynamics


Outline T c Latent heat EOS Summary<br />

’t <strong>Hooft</strong> scaling<br />

1<br />

0.8<br />

s/s SB<br />

0.6<br />

0.4<br />

0.2<br />

0<br />

SU(3)<br />

SU(4)<br />

SU(6)<br />

6 7 8 9 10<br />

λ(2πT)<br />

’t <strong>Hooft</strong> scaling fails for T ≤ 2T c .<br />

N = 4 SYM does not describe pure gauge theory.<br />

SG<br />

Large N c Thermodynamics


Outline T c Latent heat EOS Summary<br />

Conformal theory?<br />

1<br />

0.8<br />

SU(3)<br />

SU(4)<br />

SU(6)<br />

p/p SB<br />

0.6<br />

0.4<br />

0.2<br />

0<br />

0 0.2 0.4 0.6 0.8 1<br />

ε/ε SB<br />

SG<br />

Large N c Thermodynamics


Outline<br />

Outline T c<br />

Latent heat EOS Summary<br />

RG scaling and ’t <strong>Hooft</strong> scaling<br />

Latent heat<br />

Equation of state<br />

Summary<br />

SG<br />

Large N c Thermodynamics


Outline T c<br />

Main results<br />

Latent heat EOS Summary<br />

◮ Location of deconfining first order transition measured with<br />

high accuracy. Yields high precision test of RG scaling and ’t<br />

<strong>Hooft</strong> scaling. ’t <strong>Hooft</strong> coupling at T c has large 1/N c<br />

corrections near N c = 3. Signs of breakdown of the ’t <strong>Hooft</strong><br />

procedure.<br />

◮ New method developed for determination of latent heat in<br />

gluoN c plasmas. Find<br />

∆ǫ<br />

T A T 4 c<br />

= 0.388(3) − 1.61(4)<br />

Nc<br />

2 .<br />

◮ Strong N c scaling works very well for EOS. Conformal<br />

symmetry strongly broken up to T ≃ 3T c . Resummed weak<br />

coupling theory works much better in description of lattice<br />

data.<br />

SG<br />

Large N c Thermodynamics

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