Destroying Kaluza-Klein and Kerr-Newman black holes

TL;DR

This paper demonstrates that under idealized conditions, charged and rotating black holes, including Kerr-Newman and Kaluza-Klein types, can be converted into naked singularities by test particles or scalar fields, neglecting self-force effects.

Contribution

It shows that black holes can be destroyed into naked singularities using test particles or scalar fields without considering self-force or radiative effects.

Findings

Kerr-Newman black holes can be turned into naked singularities.

Kaluza-Klein black holes can be overspun by scalar fields.

Self-force and radiative effects are neglected in this analysis.

Abstract

We investigate the destroying of charged and rotating black holes in Einstein-Maxwell-(dilaton) theory. We show that a test particle with some appropriate properties in the black hole background can turn the black hole into a naked singularity. In this work, we neglect the self-force, self-energy, and radiative effects as considered by some others in literature. As the result, we are able to show that the Kerr-Newman and Kaluza-Klein black holes can be destroyed by the test particle. Furthermore, for Kaluza-Klein black hole, we consider the overspinning of the black hole by a neutral test scalar field.