LARGE TIME-SCALE FLUCTUATIONS OF THE QUARK CONDENSATE AT HIGH-TEMPERATURE

The transport theory for a quark-antiquark plasma is used to study large time-scale fluctuations of the quark condensate. The interactions between quarks are assumed to be of the Nambu-Jona-Lasino type and we restrict ourselves to the mean field (Vlasov) approximation. The space-time behavior of the fluctuations of the mean field and, consequently, of the condensate depends strongly on the form of the initial conditions for the quark distribution function. If the latter can be initially represented as a sum of the thermal background distribution plus a perturbation which is broad in momentum, then the fluctuations are suppressed in time by a mechanism analogous to that of Landau damping. On the other hand, if we add a perturbation which is peaked in momentum to the thermal background distribution, the fluctuations are not damped and behave similarly to Van Dampen modes in ordinary plasmas. © 1994 The American Physical Society.