Hard thermal loops in static external fields

TL;DR

This paper investigates the high-temperature behavior of thermal loops in static Yang-Mills and gravitational fields, showing they simplify to zero external energy and momentum evaluations, revealing a universal leading contribution.

Contribution

It demonstrates that at high temperatures, thermal loops in static fields can be approximated by zero external energy and momentum evaluations, simplifying calculations.

Findings

Hard thermal loops have a universal leading contribution at high temperatures.

Evaluating loops at zero external energies and momenta suffices in the static regime.

The approach applies to both Yang-Mills and gravitational fields.

Abstract

We study, in the imaginary-time formalism, the high temperature behavior of n-point thermal loops in static Yang-Mills and gravitational fields. We show that in this regime, any hard thermal loop gives the same leading contribution as the one obtained by evaluating the loop at zero external energies and momenta.