Viscosities in the Gluon-Plasma within a Quasiparticle Model

TL;DR

This paper extends a quasiparticle model to calculate the bulk and shear viscosities of the gluon plasma, demonstrating compatibility with the low viscosities observed in strongly coupled deconfined gluonic matter.

Contribution

It introduces an extension of a quasiparticle model to compute viscosities within an effective kinetic theory framework, linking microscopic properties to macroscopic transport coefficients.

Findings

The model reproduces lattice QCD results for the equation of state.

It shows the gluon plasma has low shear and bulk viscosities consistent with strong coupling.

The quasiparticle ansatz aligns with experimental observations of low viscosities.

Abstract

A phenomenological quasiparticle model, featuring dynamically generated self-energies of excitation modes, successfully describes lattice QCD results relevant for the QCD equation of state and related quantities both at zero and non-zero net baryon density. Here, this model is extended to study bulk and shear viscosities of the gluon-plasma within an effective kinetic theory approach. In this way, the compatibility of the employed quasiparticle ansatz with the apparent low viscosities of the strongly coupled deconfined gluonic medium is shown.