Instability of black hole formation in gravitational collapse

TL;DR

This paper demonstrates that small tangential stresses in gravitational collapse can destabilize black hole formation, potentially leading to naked singularities, thus challenging the stability of cosmic censorship.

Contribution

It introduces explicit tangential stress perturbations showing how black hole formation can be destabilized, resulting in naked singularities instead.

Findings

Small tangential stresses can change collapse outcomes

Black hole formation is unstable under certain perturbations

Naked singularities can form due to stress-induced instability

Abstract

We consider here the classic scenario given by Oppenheimer, Snyder, and Datt, for the gravitational collapse of a massive matter cloud, and examine its stability under the introduction of small tangential stresses. We show, by offering an explicit class of physically valid tangential stress perturbations, that an introduction of tangential pressure, however small, can qualitatively change the final fate of collapse from a black hole final state to a naked singularity. This shows instability of black hole formation in collapse and sheds important light on the nature of cosmic censorship hypothesis and its possible formulations. The key effect of these perturbations is to alter the trapped surface formation pattern within the collapsing cloud and the apparent horizon structure. This allows the singularity to be visible, and implications are discussed.