Dense spectrum of resonances and particle capture in a near-black-hole metric

TL;DR

This paper demonstrates that a massive body's gravitational field near the Schwarzschild radius causes a dense spectrum of narrow resonances for quantum particles, mimicking black hole absorption properties before actual black hole formation.

Contribution

It reveals that non-singular static metrics exhibit black-hole-like absorption characteristics through quantum resonances as the body's radius approaches the Schwarzschild radius.

Findings

Resonance spectrum becomes dense as R approaches r_s.

Particle capture cross section equals black hole absorption cross section.

Non-singular metrics show black-hole properties prior to formation.

Abstract

We show that a quantum scalar particle in the gravitational field of a massive body of radius R which slightly exceeds the Schwarzschild radius r_s, possesses a dense spectrum of narrow resonances. Their lifetimes and density tend to infinity in the limit R -> r_s. We determine the cross section of the particle capture into these resonances and show that it is equal to the absorption cross section for a Schwarzschild black hole. Thus, a non-singular static metric acquires black-hole properties before the actual formation of a black hole.