The chiral phase transition and the role of vacuum fluctuations

TL;DR

This paper examines how including or omitting certain terms in the free energy affects the nature and critical temperature of the chiral phase transition in a quark-meson model, emphasizing the importance of vacuum fluctuations.

Contribution

It demonstrates that neglecting specific contributions can significantly alter the predicted order and temperature of the chiral phase transition.

Findings

Omitting terms can change the transition order

Critical temperature depends on included contributions

Vacuum fluctuations play a crucial role

Abstract

We investigate the chiral phase transition in the quark-meson effective model using optimised perturbation theory to one loop. Certain terms in the free energy are frequently omitted in calculations, on the assumption that their contribution is negligible. We show that this is not necessarily the case, and that the order of the phase transition, as well as the critical temperature, depends heavily on which contributions are included.