On an exactly solvable confining quark model and its thermodynamics

TL;DR

This paper presents an exact calculation of the thermodynamics of a confining quark model inspired by QCD, showing non-trivial behavior consistent with lattice and Dyson-Schwinger results across all temperatures and densities.

Contribution

It introduces an exactly solvable confining quark model that reproduces nonperturbative thermodynamic features of QCD at all regimes.

Findings

Pressure and trace anomaly match lattice QCD results

Model exhibits stable thermodynamics at all temperatures and densities

Thermodynamics differs from free particle gas, showing non-trivial features

Abstract

We perform an exact computation of the grand partition function of a model of confined quarks at arbitrary temperatures and quark chemical potentials. The model is inspired by a version of QCD where the perturbative BRST symmetry is broken in the infrared, while perturbative QCD is recovered in the ultraviolet. The theory leads, even at tree level, to a quark mass function compatible with nonperturbative analyses of lattice simulations and Dyson-Schwinger equations. In spite of being defined at tree level, the model produces a non-trivial and stable thermodynamic behaviour at arbitrary values of temperature or chemical potential. Results for the pressure and the trace anomaly as a function of temperature qualitatively resemble those of non-perturbative interactions as observed in lattice simulations. The cold and dense thermodynamics is also contains non-trivial features, being unlike a gas of free massive particles.