Information theory in the study of anisotropic radiation

TL;DR

This paper applies information theory to analyze non-equilibrium anisotropic radiation, deriving a new closure scheme for radiative transfer equations and exploring thermodynamic properties and photon chemical potential.

Contribution

It introduces a two-parameter Eddington factor derived from information theory, providing a natural closure for radiative transfer equations in anisotropic radiation.

Findings

Recovered known Eddington factors as special cases

Linked thermodynamic properties to non-equilibrium theories

Discussed the potential for a photon chemical potential

Abstract

Information theory is used to perform a thermodynamic study of non equilibrium anisotropic radiation. We limit our analysis to a second-order truncation of the moments, obtaining a distribution function which leads to a natural closure of the hierarchy of radiative transfer equations in the so-called variable Eddington factor scheme. Some Eddington factors appearing in the literature can be recovered as particular cases of our two-parameter Eddington factor. We focus our attention in the study of the thermodynamic properties of such systems and relate it to recent nonequilibrium thermodynamic theories. Finally we comment the possibility of introducing a nonequilibrium chemical potential for photons.