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arXiv · 2108.08328

Challenging the cosmic censorship in Einstein-Maxwell-scalar theory with numerically simulated gedankenexperiments

Fabrizio Corelli·Taishi Ikeda·Paolo Pani
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Abstract

We perform extensive nonlinear numerical simulations of the spherical collapse of (charged) wavepackets onto a charged black hole within Einstein-Maxwell theory and in Einstein-Maxwell-scalar theory featuring nonminimal couplings and a spontaneous scalarization mechanism. We confirm that black holes in full-fledged Einstein-Maxwell theory cannot be overcharged past extremality and no naked singularities form, in agreement with the cosmic censorship conjecture. We show that naked singularities do not form even in Einstein-Maxwell-scalar theory, although it is possible to form scalarized black holes with charge above the Reissner-Nordstr\"om bound. We argue that charge and mass extraction due to superradiance at fully nonlinear level is crucial to bound the charge-to-mass ratio of the final black hole below extremality. We also discuss some "descalarization" mechanisms for scalarized black holes induced either by superradiance or by absorption of an opposite-charged wavepacket; in all cases the final state after descalarization is a subextremal Reissner-Nordstr\"om black hole.

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Fabrizio Corelli, Taishi Ikeda, Paolo Pani. 2021-08-18. Challenging the cosmic censorship in Einstein-Maxwell-scalar theory with numerically simulated gedankenexperiments. https://doi.org/10.1103/physrevd.104.084069

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