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arXiv · 2008.02136

Gravitational collapse of a fluid with torsion into a universe in a black hole

Nikodem Popławski
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Abstract

We consider gravitational collapse of a spherically symmetric sphere of a fluid with spin and torsion into a black hole. We use the Tolman metric and the Einstein$-$Cartan field equations with a relativistic spin fluid as a source. We show that gravitational repulsion of torsion prevents a singularity and replaces it with a nonsingular bounce. Quantum particle production during contraction helps torsion to dominate over shear. Particle production during expansion can generate a finite period of inflation and produce enormous amounts of matter. The resulting closed universe on the other side of the event horizon may have several bounces. Such a universe is oscillatory, with each cycle larger in size than the previous cycle, until it reaches the cosmological size and expands indefinitely. Our universe might have therefore originated from a black hole.

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Nikodem Popławski. 2020-08-04. Gravitational collapse of a fluid with torsion into a universe in a black hole. https://doi.org/10.31857/s0044451021030068 10.1134/s1063776121030092

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