Viscous Quark-Gluon Plasma Model Through Fluid QCD Approach

TL;DR

This paper develops a fluid QCD model for viscous quark-gluon plasma, deriving the energy-momentum tensor and identifying shear viscosity within a gauge-invariant framework.

Contribution

It introduces a novel fluid-like QCD Lagrangian for viscous plasma, maintaining gauge symmetry except for viscous terms, and connects shear viscosity to the energy-momentum tensor.

Findings

Derived the energy-momentum tensor for viscous gluonic plasma.

Identified shear viscosity as an emergent property from the model.

Maintained gauge symmetry in the fluid QCD framework.

Abstract

A Lagrangian density for viscous quark-gluon plasma has been constructed within the fluid-like QCD framework. Gauge symmetry is preserved for all terms inside the Lagrangian, except for the viscous term. The transition mechanism from point particle field to fluid field, and vice versa, is discussed. The energy momentum tensor that is relevant for the gluonic plasma having the nature of fluid bulk of gluon sea is derived within the model. By imposing conservation law in the energy momentum tensor, shear viscosity appears as extractable from the equation.