Thermal evolution of radiation spheres undergoing dissipative gravitational collapse.
Loading...
Date
2014
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
In this study we investigate the physics of a relativistic radiating star undergoing dissipative
collapse in the form of a radial heat flux. Our treatment clearly demonstrates
how the presence of shear affects the collapse process; we are in a position to contrast
the physical features of the collapsing sphere in the presence of shear with the
shear-free case. We first consider a particular exact solution found by Thirukkanesh
et al [1] which is expanding, accelerating and shearing. By employing a causal heat
transport equation of the Maxwell-Cattaneo form we show that the shear leads to an
enhancement of the core stellar temperature thus emphasizing that relaxational effects
cannot be ignored when the star leaves hydrostatic equilibrium. We also employ a
perturbative scheme to study the evolution of a spherically symmetric stellar body
undergoing gravitational collapse. The Bowers and Liang [2] static model is perturbed,
and its subsequent dynamical collapse is studied in the linear perturbative regime. We
find that anisotropic effects brought about by the differences in the radial and tangential
pressures enhance the perturbations to the temperature, and that causal and
non–causal cases yield identical profiles.
Description
Ph. D. University of KwaZulu-Natal, Durban 2014.
Keywords
General relativity (Physics), Anisotropy., Stars., Gravitational collapse., Thermodynamics., Astrophysics., Theses--Applied mathematics.