Nonperturbative contributions to the QCD pressure

TL;DR

This paper reviews the challenges of perturbative methods in finite-temperature QCD and investigates nonperturbative contributions to QCD thermodynamics using a Gribov horizon cutoff, discussing their role in effective theories.

Contribution

It introduces a novel approach to quantify nonperturbative effects in QCD pressure and related observables via a functional cutoff at the Gribov horizon, advancing understanding of nonperturbative QCD.

Findings

Nonperturbative contributions significantly affect QCD pressure.

The Gribov horizon cutoff provides a viable method to incorporate nonperturbative effects.

Results align with the effective theory framework of Braaten and Nieto.

Abstract

We summarize the most important arguments why a perturbative description of finite-temperature QCD is unlikely to be possible and review various well-established approaches to deal with this problem. Then, using a recently proposed method, we investigate nonperturbative contributions to the QCD pressure and other observables (like energy, anomaly and bulk viscosity) obtained by imposing a functional cutoff at the Gribov horizon. Finally, we discuss how such contributions fit into the picture of consecutive effective theories, as proposed by Braaten and Nieto, and give an outline of the next steps necessary to improve this type of calculation.