Strong coupling expansion of lattice gauge theories at finite temperature

Critical exponents of the chiral transition in strong coupling QCD

“…We will study the chiral phase transition in strong coupling QCD (/3 = 0) for one species of staggered fermions (f = 1). We will show that the transition is second order in this case, which is in accordance with results from mean-field calculations [10,11]. However, it is strikingly different from the first-order transition found in fourflavour QCD (nf = 4) at larger values of /3 [5].…”

“…[11). It turned out that indeed these theories are in the same universality class as three-dimensional spin models with global Z(N) symmetry as originally suggested by Svetitsky and Yaffe [21. In particular, results for the critical exponents of the SU(2) theory are in complete agreement with the exponents of the three-dimensional Ising model [31. Compared to these high-precision results the analysis of the critical behaviour of full QCD, i.e in the presence of dynamical quarks, is still exploratory.…”

“…The mean-field free energy is given by where Z,~denotes the single-site partition function for SU(3) [10,11], …”

“…The finite-temperature behaviour of strong coupling QCD has been studied in mean-field theory [10,11] and also numerically, using the monomer-dimer-polymer (MDP) algorithm [13,14,171.These studies suggest that the finite-temperature chiral phase transition is continuous for /3 = 0. The MDP algorithm is particularly well suited to the analysis of strong coupling QCD as it allows a straightforward calculation of fermionic observables like the order parameter or the susceptibility.…”

Phase diagram at finite temperature and quark density in the strong coupling limit of lattice QCD for color SU(3)

“…One of the most instructive approximations to investigate the finite temperature T and chemical potential of QCD is to consider the strong coupling limit of lattice QCD [21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39]. In fact, effective free energy at finite T of strong coupling lattice QCD was analytically derived and predicted the second order chiral symmetry restoration temperature [28,29].…”