Hard-thermal-loop QCD Thermodynamics

TL;DR

This paper reviews a three-loop hard-thermal-loop perturbation theory approach to QCD thermodynamics, showing it aligns well with lattice data down to about twice the critical temperature, improving understanding of quark-gluon plasma properties.

Contribution

It presents a three-loop HTL perturbation calculation for QCD thermodynamics applicable to various N_c and N_f, demonstrating improved agreement with lattice results.

Findings

Three-loop HTL results agree with lattice data down to T ~ 2 T_c.

Resummed perturbation theory improves convergence over naive methods.

The approach is applicable for general N_c and N_f.

Abstract

Naively resummed perturbative approximations to the thermodynamic functions of QCD do not converge at phenomenologically relevant temperatures. Here we review recent results of a three-loop hard-thermal-loop perturbation theory calculation of the thermodynamic functions of a quark-gluon plasma for general N_c and N_f. We show comparisons of our recent results with lattice data from both the hotQCD and Wuppertal-Budapest groups. We demonstrate that the three-loop hard-thermal-loop perturbation result for QCD thermodynamics agrees with lattice data down to temperatures T ~ 2 T_c.