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arXiv · 2312.02032

Shell-crossings and shock formation during gravitational collapse in effective loop quantum gravity

Francesco Fazzini·Viqar Husain·Edward Wilson-Ewing
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Abstract

Effective models of gravitational collapse in loop quantum gravity for the Lema\^itre-Tolman-Bondi spacetime predict that collapsing matter reaches a maximum finite density, bounces, and then expands outwards. We show that in the marginally bound case, shell-crossing singularities commonly occur for inhomogeneous initial profiles of the dust energy density; this is the case in particular for all profiles that are continuous and of compact support, including configurations arbitrarily close to the Oppenheimer-Snyder model. When a shell-crossing singularity occurs, it is necessary to seek weak solutions to the dynamics; we argue that weak solutions typically contain shock waves.

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Francesco Fazzini, Viqar Husain, Edward Wilson-Ewing. 2023-12-04. Shell-crossings and shock formation during gravitational collapse in effective loop quantum gravity. https://doi.org/10.1103/physrevd.109.084052

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