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arXiv · 1211.2631

Destroying extremal Kerr-Newman black holes with test particles

Sijie Gao·Yuan Zhang
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Abstract

It has been shown that a nearly extremal black hole can be overcharged or overspun by a test particle if radiative and self-force effects are neglected, indicating that the cosmic censorship might fail. In contrast, the existing evidence in literature suggests that an extremal black hole cannot be overcharged or overspun in a similar process. In this paper, we show explicitly that even an exactly extremal black hole can be destroyed by a test particle, leading to a possible violation of the cosmic censorship. By considering higher order terms, which were neglected in previous analysis, we show that the violation is generic for any extremal Kerr-Newman black hole with nonvanishing charge and angular momentum. We also find that the allowed parameter range for the particle is very narrow, indicating that radiative and self-force effects should be considered and may prevent violation of the cosmic censorship.

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Sijie Gao, Yuan Zhang. 2013-02-25. Destroying extremal Kerr-Newman black holes with test particles. https://doi.org/10.1103/physrevd.87.044028

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