Ma. Stephanov, CHIRAL-SYMMETRY AT FINITE-T, THE PHASE OF THE POLYAKOV LOOP AND THE SPECTRUM OF THE DIRAC OPERATOR, Physics letters. Section B, 375(1-4), 1996, pp. 249-254
A recent Monte Carlo study of quenched QCD showed that the chiral cond
ensate is non-vanishing above T-c in the phase where the average of th
e Polyakov loop P is complex. We show how this is related to the depen
dence of the spectrum of the Dirac operator on the boundary conditions
in Euclidear. time. We use a random matrix model to calculate the den
sity of small eigenvalues and the chiral condensate as a function of a
rg P. The chiral symmetry is restored in the arg P = 2 pi/3 phase at a
higher T than in the arg P = 0 phase. In the phase arg P = pi of the
SU(2) gauge theory the chiral condensate stays nonzero for all T.