Overcharging Extremal Black Holes

TL;DR

This paper demonstrates that in certain modified gravity theories, extremal black holes can be overcharged, challenging the Weak Cosmic Censorship conjecture and constraining theory parameters.

Contribution

It shows that overcharging extremal black holes is possible in modified gravity, providing new constraints on theory parameters using the WCC criterion.

Findings

Overcharging extremal black holes in modified gravity theories is feasible.

The method reproduces known bounds on Einstein-aether black hole parameters.

Constraints on parameters are derived from the validity of the WCC.

Abstract

The Weak Cosmic Censorship (WCC) conjecture can be used as a consistency criterion for any viable modification over general relativity (GR). We employ this idea to show that in contrast to the black holes in GR, it is indeed possible to overcharge modified extremal black hole solutions. Demanding the validity of WCC, we put some stringent constraints on various parameters of the theory. In particular, for charged Einstein-aether black hole, our method is strong enough to reproduce the identical bound on the parameter obtained previously from entirely different considerations.