Three-loop HTL gluon thermodynamics at intermediate coupling

TL;DR

This paper computes thermodynamic functions of pure-glue QCD at three-loop order using HTLpt, showing good agreement with lattice results down to about three times the critical temperature, and demonstrating HTLpt's potential for LHC-relevant temperatures.

Contribution

It extends HTLpt to three-loop order for pure-glue QCD thermodynamics, providing a systematic approach compatible with lattice data at intermediate temperatures.

Findings

HTLpt at three-loop order agrees with lattice results for pressure, energy density, and entropy.

Results are valid down to temperatures around 3 times the critical temperature.

HTLpt can be used to calculate static and dynamic quantities relevant at LHC energies.

Abstract

We calculate the thermodynamic functions of pure-glue QCD to three-loop order using the hard-thermal-loop perturbation theory (HTLpt) reorganization of finite temperature quantum field theory. We show that at three-loop order hard-thermal-loop perturbation theory is compatible with lattice results for the pressure, energy density, and entropy down to temperatures $T\simeq3\;T_c$. Our results suggest that HTLpt provides a systematic framework that can used to calculate static and dynamic quantities for temperatures relevant at LHC.