Viscosity, wave damping and shock wave formation in cold hadronic matter

TL;DR

This paper investigates how viscosity affects wave propagation and shock formation in cold hadronic matter and quark-gluon plasma, revealing significant damping in hadronic matter with potential phenomenological implications.

Contribution

It provides a comparative analysis of wave dynamics in hadronic matter and quark-gluon plasma, incorporating viscosity effects using the Navier-Stokes equation and specific equations of state.

Findings

Viscosity strongly damps wave propagation in hadron gas.

Viscosity hinders shock wave formation in hadron gas.

Differences in wave behavior may serve as signatures for quark-gluon plasma.

Abstract

We study linear and nonlinear wave propagation in a dense and cold hadron gas and also in a cold quark gluon plasma, taking viscosity into account and using the Navier-Stokes equation. The equation of state of the hadronic phase is derived from the nonlinear Walecka model in the mean field approximation. The quark gluon plasma phase is described by the MIT equation of state. We show that in a hadron gas viscosity strongly damps wave propagation and also hinders shock wave formation. This marked difference between the two phases may have phenomenological consequences and lead to new QGP signatures.