Cosmic censorship in overcharging a Reissner-Nordstr\"{o}m black hole via charged particle absorption

TL;DR

This paper investigates whether a charged particle can overcharge a Reissner-Nordström black hole and violate cosmic censorship, emphasizing the importance of back reaction effects which prevent overcharging in realistic scenarios.

Contribution

It demonstrates that back reaction effects prevent overcharging of black holes, challenging previous claims based on test particle approximations.

Findings

Back reaction effects are crucial in overcharging scenarios.

Reissner-Nordström black holes cannot be overcharged via charged particle absorption.

Cosmic censorship remains valid when back reaction effects are properly considered.

Abstract

There is a claim that a static charged black hole (Reissner-Nordstr\"{o}m black hole) can be overcharged by absorbing a charged test particle. If it is true, it might give a counter example to the weak cosmic censorship conjecture, which states that spacetime singularities are never observed by a distant observer. However, so far the proposed process has only been analyzed within a test particle approximation. Here we claim that the back reaction effects of a charged particle cannot be neglected when judging whether the suggested process is really a counter example to the cosmic censorship conjecture or not. Furthermore, we argue that all the back reaction effects can be properly taken into account when we consider the trajectory of a particle on the border between the plunge and bounce orbits. In such marginal cases we find that the Reissner-Nordstr\"{o}m black hole can never be overcharged via the absorption of a charged particle. Since all the plunge orbits are expected to have a higher energy than the marginal orbit, we conclude that there is no supporting evidence that indicates the violation of the cosmic censorship in the proposed overcharging process.