On the infrared behavior of the shear spectral function in hot Yang-Mills theory

TL;DR

This paper improves the understanding of the infrared behavior of the shear spectral function in hot Yang-Mills theory by correcting previous errors and incorporating Hard Thermal Loop resummation, enabling better application in related correlators and sum rules.

Contribution

It corrects a technical error in the two-loop spectral function calculation and extends it with Hard Thermal Loop resummation for improved infrared behavior.

Findings

Infrared behavior of the spectral function is significantly improved.

The corrected and extended result can be directly used in imaginary time correlators.

Enhanced accuracy in shear sum rule applications.

Abstract

We revisit the determination of the two-loop spectral function in the shear channel of hot Yang-Mills theory. Correcting a technical error in an earlier computation and extending the result with a leading order Hard Thermal Loop resummation is seen to improve the infrared behavior of the quantity significantly. This makes it possible to straightforwardly use the result in the corresponding imaginary time correlator and the shear sum rule.