Thermal Conduction in Systems out of Hydrostatic Equilibrium

TL;DR

This paper investigates how thermal conduction influences the evolution of a relativistic fluid immediately after it leaves hydrostatic equilibrium, emphasizing the role of a causality-constrained thermodynamic parameter.

Contribution

It introduces a new analysis of thermal conduction effects in relativistic fluids out of equilibrium, highlighting the importance of a causality-bound parameter in their evolution.

Findings

Evolution depends critically on a thermodynamic parameter.

The parameter is constrained by causality.

Thermal relaxation time governs the dynamics.

Abstract

We analyse the effects of thermal conduction in a relativistic fluid, just after its departure from hydrostatic equilibrium, on a time scale of the order of thermal relaxation time. It is obtained that the resulting evolution will critically depend on a parameter defined in terms of thermodynamic variables, which is constrained by causality requirements.