A stellar model with diffusion in general relativity
Journal article, 2017

We consider a spherically symmetric stellar model in general relativity whose interior consists of a pressureless fluid undergoing microscopic velocity diffusion in a cosmological scalar field. We show that the diffusion dynamics compel the interior to be spatially homogeneous, by which one can infer immediately that within our model, and in contrast to the diffusion-free case, no naked singularities can form in the gravitational collapse. We then study the problem of matching an exterior Bondi type metric to the surface of the star and find that the exterior can be chosen to be a modified Vaidya metric with variable cosmological constant. Finally, we study in detail the causal structure of an explicit, self similar solution.

General relativity

Gravitational collapse

Diffusion

Self-similarity

Author

Artur Alho

Instituto Superior Tecnico

Simone Calogero

Chalmers, Mathematical Sciences, Analysis and Probability Theory

University of Gothenburg

Journal of Geometry and Physics

0393-0440 (ISSN)

Vol. 120 62-72

Subject Categories

Computational Mathematics

DOI

10.1016/j.geomphys.2017.05.018

More information

Latest update

6/20/2018