Quantum gravity of dust collapse: shock waves from black holes

TL;DR

This paper investigates quantum gravitational collapse of dust, revealing that black holes form and dissipate as shockwaves with a lifetime proportional to the square of their mass, challenging semiclassical expectations.

Contribution

It introduces a novel quantum gravity model for dust collapse using polymer quantization, showing black hole dynamics differ from semiclassical predictions.

Findings

Trapped surfaces form and then vanish as shockwaves.

Black hole lifetime scales with the square of its mass.

No mass inflation occurs at inner horizons.

Abstract

We study the quantum gravitational collapse of spherically symmetric pressureless dust. Using an effective equation derived from a polymer quantization in the connection-triad phase space variables of general relativity, we find numerically, for a variety of initial dust configurations, that (i) trapped surfaces form and disappear as an initially collapsing density profile evolves into an outgoing shockwave; (ii) black hole lifetime is proportional to the square of its mass; and (iii) there is no mass inflation at inner apparent horizons. These results provide a substantially different view of black hole formation and subsequent evolution than found from semiclassical analyses.