Entropy Production in Gluodynamics in temporal axial gauge in 2+1 dimensions

TL;DR

This paper investigates entropy production in 2+1 dimensional gluodynamics using the Kadanoff-Baym equation, demonstrating entropy increase during relaxation from anisotropic to isotropic distributions due to off-shell scattering.

Contribution

It introduces a kinetic entropy framework in non-Abelian gauge theory and provides numerical evidence of entropy production in 2+1 dimensions.

Findings

Entropy increases during relaxation from anisotropic to isotropic states.

Entropy production is driven by off-shell scattering of transverse modes.

Numerical simulations confirm the H-theorem in this context.

Abstract

Entropy production in non-Abelian gauge theory is discussed in the limit of vanishing classical fields. Based on the Kadanoff-Baym equation with the leading order self-energy in the temporal axial gauge, the kinetic entropy is introduced and is proven to increase for a given self-energy. Numerical simulation of the Kadanoff-Baym equation for the non-Abelian gauge theory is performed in 2+1 dimensions. Starting from anisotropic distribution in momentum space, relaxation to isotropic distribution proceeds and the entropy is produced due to off-shell scattering of massive transverse polarization mode as expected from the proof of the H-theorem.