Fluctuations of Goldstone modes and the chiral transition in QCD

TL;DR

This paper investigates how thermal fluctuations of Goldstone modes affect the chiral condensate near the QCD chiral transition, revealing characteristic mass dependencies and divergence behaviors.

Contribution

It demonstrates the impact of Goldstone mode fluctuations on the chiral condensate and susceptibility near the transition, connecting QCD behavior with 3D O(N) models.

Findings

Chiral condensate depends on the square root of light quark mass below Tc.

Chiral susceptibility diverges as 1/sqrt(m_l) in the chiral limit.

Goldstone mode fluctuations significantly influence chiral transition dynamics.

Abstract

We provide evidence for the influence of thermal fluctuations of Goldstone modes on the chiral condensate at finite temperature. We show that at fixed temperature, T<Tc, in the vicinity of the chiral transition temperature this leads to a characteristic dependence of the chiral condensate on the square root of the light quark mass (m_l), which is expected for 3-dimensional models with broken O(N) symmetry. As a consequence the chiral susceptibility shows a strong quark mass dependence for all temperatures below Tc and diverges like 1/sqrt(m_l) in the chiral limit.