Shear viscosity and spectral function of the quark matter

TL;DR

This paper investigates the shear viscosity of quark matter using the Kubo-Mori formula, relating it to the quark spectral function, and explores how it varies with temperature, density, and spectral width approximations.

Contribution

It introduces a spectral function-based approach to compute shear viscosity in quark matter and analyzes its dependence on spectral width, temperature, and density.

Findings

Shear viscosity decreases with increasing spectral width.

Viscosity varies with temperature and density.

Spectral function approximation impacts viscosity calculations.

Abstract

We discuss the shear viscosity of the quark matter by using the Kubo-Mori formula. It is found that the shear viscosity is expressed in terms of the quark spectral function. If the spectral function is approximated by a modified Bright-Wigner type, the viscosity decreases as the width of the spectral function increases. We also discuss dependence of the shear viscosity on the temperature and the density.