Relativistic dynamics of the motion of heat

Abstract

The motion of heat can be described by a thermal energy–momentum tensor. A general description of heat conduction in the geometrical language is developed based on a two-phase continuum model within the framework of relativistic continuum dynamics, and the momentum balance equation of heat, or the general heat conduction equation (GHCE), is derived by the balance equation of the thermal energy–momentum tensor. We demonstrate that the low-speed limit of the GHCE coincides the former version of GHCE of the thermomass theory that is based on the energy–mass equivalence and Newtonian dynamics. Numerical solutions of the GHCE are also provided to demonstrate that the GHCE not only overcomes the paradox of instantaneous heat propagation of the Fourier’s law, but also resolves the defect of the CV model that temperatures may drop below absolute zero under some conditions. The present work formulates a general description of the thermal transport processes, and can provide a deeper insight into the heat transfer discipline from the relativistic point of view.