A covariant variational approach to Yang-Mills Theory at finite temperatures

TL;DR

This paper extends a covariant variational method to finite-temperature SU(N) Yang-Mills theory, demonstrating that the approach aligns qualitatively with lattice results for ghost and gluon propagators.

Contribution

It introduces a finite-temperature extension of the covariant variational approach for Yang-Mills theory, maintaining renormalization consistency and matching lattice data qualitatively.

Findings

Ghost and gluon propagators agree with lattice results

Renormalization uses the same counterterms as zero temperature

Method successfully extends to non-zero temperatures

Abstract

We extend the covariant variational approach for SU(N) Yang-Mills theory in Landau gauge to non-zero temperatures. The renormalization of the zero-temperature case is revisited and it is shown that the same counterterms are sufficient to render the low-order Green's function finite at non-zero temperature. We compute the ghost and gluon propagator numerically and show that it agrees in all qualitative respects with the results of high-precision lattice calculations.