Testing the Cosmic Censorship Conjecture with point particles: the effect of radiation reaction and the self-force

TL;DR

This paper investigates whether radiation reaction and self-force effects prevent over-spinning nearly extremal black holes with particles, supporting the cosmic censorship conjecture by showing these effects can inhibit naked singularity formation.

Contribution

It provides a detailed analysis of back-reaction effects, especially the conservative self-force, in the context of over-spinning black holes with particles, extending previous work.

Findings

Radiative effects can be neglected for certain trajectories leading to naked singularities.

Conservative self-force likely prevents the formation of naked singularities in these scenarios.

Supports the cosmic censorship conjecture by demonstrating self-force effects are protective.

Abstract

A classical thought-experiment to destroy black holes was envisaged by Wald in 1974: it consists of throwing particles with large angular momentum into an extremal black hole, checking whether their capture can over-spin the black hole past the extremal limit and create a naked singularity. Wald showed that in the test-particle limit, particles that would be otherwise capable of producing naked singularities are simply scattered. Recently Jacobson and Sotiriou showed that if one considers instead a black hole that is almost, but not exactly extremal, then in the absence of backreaction effects particle capture could indeed over-spin the spacetime above the Kerr limit. Here we analyze back-reaction effects and show that for some of the trajectories giving rise to naked singularities, radiative effects can be neglected. However, for these orbits the conservative self-force is important, and seems to have the right sign to prevent the formation of naked singularities.