2016/02/29 by Artur Alho, Simone Calogero · 1 citation
Mathematics · Physics and Astronomy · #Black Holes and Theoretical Physics #Classical mechanics #Cosmological constant #Cosmology and Gravitation Theories #General relativity #Gravitation #Gravitational singularity #Introduction to the mathematics of general relativity #Mathematical physics #Metric (unit) #Numerical relativity #Physics #Quantum mechanics #Relativity and Gravitational Theory #Scalar field #Theoretical motivation for general relativity #Theoretical physics #gr-qc #math-ph #math.MP
paper · pdf · doi:10.1016/j.geomphys.2017.05.018
16 pages, 2 figures. v2: 17 pages, matches final published version
arxiv created 2017/06/22 · openalex publication_date 2017/06/22 · arxiv updated 2017/08/23 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
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.