Formation of nonsingular spherical black holes with holonomy corrections

TL;DR

This paper develops a loop quantum gravity-inspired model of spherical black holes, replacing singularities with finite curvature boundaries and predicting stable Planck-scale remnants.

Contribution

It introduces a covariant correction-based canonical model that generalizes Lemaître-Tolman-Bondi spacetimes and describes nonsingular black hole formation.

Findings

Singularity replaced by a finite curvature boundary.

Stable black-hole remnants of Planckian mass predicted.

Observers never reach the boundary, implying a modified black hole interior.

Abstract

We present a canonical model of spherical gravity with covariant corrections motivated by loop quantum gravity. The effective Hamiltonian defines univocally a family of geometries that generalizes the Lema\^itre-Tolman-Bondi spacetimes, and they can be matched to the vacuum of the theory across a timelike hypersurface comoving with the flow of matter. Such is precisely the complete spacetime picture of a spherical star subject to its own gravitational pull. The singularity gets replaced with a spacelike boundary in the trapped region of spacetime, where the curvature remains finite, and the area of the orbits of the spherical symmetry group attains its infimum. Observers falling into the black hole are doomed to travel forever towards this boundary without ever reaching it. The theory also predicts the formation of stable black-hole remnants of Planckian mass.