Nonuniform-temperature effects on the phase transition in an Ising-like model

TL;DR

This paper explores how spatially nonuniform temperatures affect the QCD chiral phase transition, revealing that such effects can raise the transition temperature, enhance fluctuations, and suppress critical phenomena, with implications for heavy-ion collision experiments.

Contribution

It introduces a method to evaluate nonuniform-temperature effects on the QCD phase transition using an Ising-like model, linking temperature inhomogeneities to critical behavior modifications.

Findings

Nonuniform temperatures can lift the phase transition temperature.

Fluctuations and correlation length are enhanced near the transition.

Critical phenomena are suppressed by nonuniform temperature effects.

Abstract

In this study, we investigate the spatially nonuniform-temperature effects on the QCD chiral phase transition in the heavy-ion collisions. Since the QCD effective theory and the Ising model belong to the same universality class, we start our discussion by mimicking the QCD effective potential with an Ising-like effective potential. In contrast to the dynamical slowing down effects which delays the phase transition from quark-gluon-plasma to hadron gas, the spatially nonuniform-temperature effects show a possibility to lift the phase transition temperature. Besides, both the fluctuations and the correlation length are enhanced in the phase transition region. Furthermore, the critical phenomena is strongly suppressed like as the critical slowing down effects. The underlying mechanism is the nonzero-momentum mode fluctuations of the order parameter induced by the nonuniform temperature. Our study provides a method to evaluate the nonuniform-temperature effects, and illustrate its potential influence on analyzing the QCD phase transition signals at RHIC.