Challenging event horizons with spin (3/2) fields

TL;DR

This paper investigates whether massless spin (3/2) fields can destroy event horizons of Kerr black holes, showing that such perturbations can violate cosmic censorship and the third law of black hole dynamics.

Contribution

It provides a detailed analysis of spin (3/2) field interactions with Kerr black holes, including absorption probabilities and backreaction effects, revealing potential violations of fundamental black hole conjectures.

Findings

Small perturbations can destroy extremal black hole horizons.

Spin (3/2) fields can violate cosmic censorship.

Fermionic fields do not satisfy the null energy condition.

Abstract

We attempt to destroy the event horizons of Kerr black holes by perturbing them with massless spin (3/2) fields. We carry out a detailed analysis by incorporating the explicit form of the absorption probabilities and backreaction effects due to the self energy of the test fields. For extremal and nearly extremal black holes, backreaction effects dominate for perturbations with large magnitudes. However, small perturbations can destroy the event horizons of extremal black holes and drive nearly extremal black holes closer to extremality. Eventually, nearly extremal black holes reach a certain stage where they can be continuously driven to extremality and beyond. Both the cosmic censorship conjecture and the third law of black hole dynamics can be violated by spin (3/2) fields. This directly follows from the fact that fermionic fields do not satisfy the null energy condition. Therefore this result does not contradict with the fact that cosmic censorship and the laws of black hole mechanics remain valid for perturbations satisfying the null energy condition.