On the microscopic nature of dissipative effects in special relativistic kinetic theory

TL;DR

This paper develops a microscopic kinetic theory framework for relativistic gases, providing a novel physical interpretation of dissipative effects like heat flux and viscous stress through Lorentz transformations and chaotic velocities.

Contribution

It introduces a new microscopic formulation linking dissipative fluxes to chaotic kinetic energy and momentum flux in relativistic gases, establishing a kinetic foundation for relativistic transport equations.

Findings

Dissipative effects identified as averages of chaotic kinetic energy and momentum flux.

Lorentz transformation links laboratory and comoving frames for flux analysis.

Provides a novel kinetic foundation for relativistic transport equations.

Abstract

A microscopic formulation of the definition of both the heat flux and the viscous stress tensor is proposed in the framework of kinetic theory for relativistic gases emphasizing on the physical nature of such fluxes. A Lorentz transformation is introduced as the link between the laboratory and local comoving frames and thus between molecular and chaotic velocities. With such transformation, the dissipative effects can be identified as the averages of the chaotic kinetic energy and the momentum flux out of equilibrium, respectively. Within this framework, a kinetic foundation of the ensuing transport equations for the relativistic gas is achieved. To our knowledge, this result is completely novel.