General Relativistic Radiant Shock Waves in the Post-Quasistatic Approximation

TL;DR

This paper models the evolution of radiant shock waves in relativistic spheres using a post-quasistatic approximation, highlighting the effects of anisotropy, dissipation, and relativistic speeds on the shock dynamics and energy conditions.

Contribution

It introduces a novel method to analyze self-gravitating relativistic spheres with shock fronts, incorporating anisotropic phases and radiation transfer within the post-quasistatic framework.

Findings

Shock speeds can become relativistic and exceed light speed at critical points.

Energy conditions are highly sensitive to anisotropy, especially the strong energy condition.

Radiation pressure can dominate over matter pressure in the core region.

Abstract

An evolution of radiant shock wave front is considered in the framework of a recently presented method to study self-gravitating relativistic spheres, whose rationale becomes intelligible and finds full justification within the context of a suitable definition of the post-quasistatic approximation. The spherical matter configuration is divided into two regions by the shock and each side of the interface having a different equation of state and anisotropic phase. In order to simulate dissipation effects due to the transfer of photons and/or neutrinos within the matter configuration, we introduce the flux factor, the variable Eddington factor and a closure relation between them. As we expected the strength of the shock increases the speed of the fluid to relativistic values and for some critical ones is larger than light speed. In addition, we find that energy conditions are very sensible to the anisotropy, specially the strong one. As a special feature of the model, we find that the contribution of the matter and radiation to the radial pressure are the same order of magnitude as in the mant as in the core, moreover, in the core radiation pressure is larger than matter pressure.