Non-equilibrium fluctuations at the QCD phase transition

TL;DR

This paper investigates the non-equilibrium behavior of the sigma field during the QCD chiral phase transition, highlighting how fluctuations influence sigma excitations in a dynamic, dissipative environment.

Contribution

It introduces a Langevin-type approach to model non-equilibrium fluctuations of the sigma field coupled with a fluid dynamic description of the quark medium.

Findings

Increased sigma excitation intensity due to non-equilibrium fluctuations

Dissipative effects influence phase transition dynamics

Fluctuations are significant at the first order phase transition

Abstract

We study the chiral phase transition by the non-equilibrium propagation of the sigma field. A quark fluid acts as a heat bath in local thermal equilibrium and evolves fluid dynamically. We allow for dissipative processes and fluctuations since the sigma field is propagated according to a Langevin-type equation of motion. Non-equilibrium fluctuations at the first order phase transition lead to an increase in the intensity of sigma excitations.