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arXiv · 2404.12243

Cosmic inflation prevents singularity formation in collapse into a Hayward black hole

Michał Bobula
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Abstract

We construct a (quantum mechanically) modified model for the Oppenheimer-Snyder collapse scenario where the exterior of the collapsing dust ball is a Hayward black hole spacetime and the interior is a dust Friedmann-Robertson-Walker cosmology. This interior cosmology is entirely determined by the junction conditions with the exterior black hole. It turns out to be non-singular, displaying a power-law contraction which precedes a de Sitter phase or, reversely, a power-law expansion followed by a de Sitter era. We demonstrate that cosmic inflation in the collapse setting is a mechanism that decelerates collapsing matter, thereby preventing singularity formation. We also analyse the global causal structure and the viability of the model.

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Michał Bobula. 2024-04-18. Cosmic inflation prevents singularity formation in collapse into a Hayward black hole. https://doi.org/10.1088/1361-6382/adbc40

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