Fluctuations and correlations in Polyakov loop extended chiral fluid dynamics

Abstract

We study nonequilibrium effects at the QCD phase transition within the framework of Polyakov loop extended chiral fluid dynamics. The quark degrees of freedom act as a locally equilibrated heat bath for the sigma field and a dynamical Polyakov loop. Their evolution is described by a Langevin equation with dissipation and noise. At a critical point we observe the formation of long-range correlations after equilibration. During a hydrodynamical expansion nonequilibrium fluctuations are enhanced at the first order phase transition compared to the critical point.