Gravitational Collapse with Torsion and Universe in a Black Hole

TL;DR

This paper explores how torsion in gravitational collapse prevents singularities, leading to a bouncing universe inside a black hole that can oscillate and eventually expand indefinitely, possibly originating from another universe.

Contribution

It introduces a model where torsion prevents singularities during collapse, resulting in a nonsingular bouncing universe with potential for oscillations and eventual dark energy-driven expansion.

Findings

Torsion prevents singularity formation during collapse.

Quantum particle creation induces a bounce and inflation.

The universe inside a black hole can oscillate and expand indefinitely.

Abstract

We consider gravitational collapse of a sphere of a fluid with torsion generated by spin, which forms 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, replacing it with a nonsingular bounce. Quantum particle creation during contraction prevents shear from overcoming torsion. Particle creation during expansion can generate a finite period of inflation and produce large 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 than the preceding cycle, until it reaches a size at which dark energy dominates and expands indefinitely. Our universe might have therefore originated from a black hole existing in another universe.