A family of quantum interiors for ordinary and stringy black holes II: Geometric considerations and global properties

TL;DR

This paper explores a family of quantum interior spacetimes for black holes, demonstrating their physical plausibility, including isotropization and stringy core features, within a semiclassical framework, advancing the understanding of regular, self-gravitating black holes.

Contribution

It proves the uniqueness and physical properties of a specific family of quantum interior solutions, including the possibility of stringy cores, without relying on mass shells.

Findings

The family exhibits isotropization far from the regularization scale.

Mathematically, the family is shown to be unique and generic.

Includes analysis of stringy core possibilities within semiclassical gravity.

Abstract

A family of spacetimes suitable for describing the matter conditions of a static, spherically symmetric quantum vacuum is studied, as well as its reliability for describing a regular model for the interior of a semiclassical, static black hole ---without ever invoking a mass shell for the final object. In paper I, this condition was seen to limit the search to only one, distinguished family, that was investigated in detail. Here it will be proven that, aside from being mathematically generic (in its uniqueness), this family exhibits beautiful physical properties, that one would reasonably demand from a collapse process, including the remarkable result that isotropization may take place conveniently far from the (unavoidable) regularization scale. The analysis is also extended in order to include the possibility of a stringy core, always within the limits imposed by the semiclassical approach to gravitation. This constitutes a first approximation to the final goal of trying to characterize a regular, self-gravitating, stringy black hole.