Interaction of Fermionic Matter and ECSK Black Hole with Torsion

TL;DR

This paper explores how fermionic matter interacting with torsion in ECSK gravity can prevent black hole singularities, leading to a bouncing universe scenario that addresses key cosmological problems without fine-tuning.

Contribution

It introduces a model where fermion-torsion interactions create a repulsive potential, resulting in nonsingular black holes and a natural solution to flatness and horizon problems.

Findings

Fermionic matter experiences a repulsive potential at high densities.

Black hole interiors can bounce into a new universe without singularities.

The model aligns with current cosmological parameters and solves classical problems.

Abstract

The interactions between the spin of fermionic matter and torsion in the Einstein-Cartan-Sciama-Kibble (ECSK) theory of gravity provides a repulsive gravitational potential at the very dense states of fermionic matter, which prevents the formation of black hole singularities inside the deeper horizon. While the fermionic matter in the black hole is attracted by the black hole at the beginning, after a critical point it is repelled to bounce at a critical high density and then expand into other side of the horizon as a newly created space, which may be considered as a nonsingular, closed universe. We constructed the action of these fermions in a black hole with torsion in the framework of ECSK theory of gravity from which the free Dirac action is inferred to obtain the interaction potential. The creation of a bouncing universe with the extremely repulsive potential may be related to the running vacuum and the modified Friedmann equations yield the consistent cosmological parameters with present FRW universe. Finally, this scenario naturally solves the flatness and horizon problems of cosmology without introducing finely tuned scalar fields, or more complicated functions of the Ricci Scalar R in the gravitational action.