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arXiv · 2103.01321

Black hole in asymmetric cosmological bounce

Daniela Pérez·Santiago E. Perez Bergliaffa·Gustavo E. Romero
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Abstract

We determine the causal structure of the McVittie spacetime for a cosmological model with an asymmetric bounce. The analysis includes the computation of trapping horizons, regular, trapped, and anti-trapped regions, and the integration of the trajectories of radial null geodesics before, during, and after the bounce. We find a trapped region since the beginning of the contracting phase up to shortly before the bounce, thus showing the existence of a black hole. When the universe reaches a certain minimum scale in the contracting phase, the trapping horizons disappear and the central singularity becomes naked. These results suggest that neither a contracting nor an expanding universe can accommodate a black hole at all times.

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Daniela Pérez, Santiago E. Perez Bergliaffa, Gustavo E. Romero. 2021-03-01. Black hole in asymmetric cosmological bounce. https://doi.org/10.1002/asna.202113883

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