Matter accretion versus semiclassical bounce in Schwarzschild interior

TL;DR

This paper presents a semiclassical model of a Schwarzschild black hole interior where the singularity is replaced by a stable bounce, driven by vacuum polarization effects, with negligible quantum and classical perturbations.

Contribution

It introduces a stable semiclassical bounce model replacing the Schwarzschild singularity, considering quantum vacuum polarization and classical matter effects as negligible perturbations.

Findings

The model replaces the singularity with a regular bounce.

Quantum contributions from topology and particle production are negligible.

Classical accretion does not destabilize the bounce.

Abstract

We discuss the properties of the previously constructed model of a Schwarzschild black hole interior where the singularity is replaced by a regular bounce, ultimately leading to a white hole. The model is semiclassical in nature and uses as a source of gravity the effective stress-energy tensor (SET) corresponding to vacuum polarization of quantum fields, and a minimum spherical radius is a few orders of magnitude larger than the Planck length, so that the effects of quantum gravity should be still negligible. We estimate the other quantum contributions to the effective SET, caused by a nontrivial topology of spatial sections and particle production from vacuum due to a nonstationary gravitational field and show that these contributions are negligibly small as compared to the SET due to vacuum polarization. The same is shown for such classical phenomena as accretion of different kinds of matter to the black hole and its further motion to the would-be singularity. Thus, in a clear sense, our model of a semiclassical bounce instead of a Schwarzschild singularity is stable under both quantum and classical perturbations.