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arXiv · 2309.04368

Can quasi-circular mergers of charged black holes produce extremal black holes?

Gabriele Bozzola·Vasileios Paschalidis
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Abstract

In contrast to energy and angular momentum, electric charge is conserved in mergers of charged black holes. This opens up the possibility for the remnant to have Kerr-Newman parameter $χ^{2} + λ^{2}$ greater than 1 (with $χ$ and $λ$ being the black hole dimensionless spin and dimensionless charge, respectively), which is forbidden by the cosmic censorship conjecture. In this paper, we investigate whether a naked singularity can form in quasi-circular mergers of charged binary black holes. We extend a theoretical model to estimate the final properties of the remnant left by quasicircular mergers of binary black holes to the charged case. We validate the model with numerical-relativity simulations, finding agreement at the percent level. We then use our theoretical model to argue that while naked singularities cannot form following quasi-circular mergers of non-spinning charged binary black holes, it is possible to produce remnants that are arbitrarily close to the extremal limit.

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Gabriele Bozzola, Vasileios Paschalidis. 2023-09-08. Can quasi-circular mergers of charged black holes produce extremal black holes?. https://doi.org/10.1103/physrevd.108.064010

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