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arXiv · 2508.17665

Testing the weak cosmic censorship conjecture via test particle induced overcharging/overspinning of Kerr Newman modified gravity black hole

Abstract

We investigate the weak cosmic censorship conjecture (WCCC) violation through the absorption of a charged, rotating test particle by Kerr Newman spacetime in modified gravity (KN MOG). The result is sensitive to multiple factors, including the sign of the particle's charge relative to that of the black hole, as well as the direction of rotation of the particle and the black hole. Additionally, the combined effect of the MOG parameter, the black hole's charge and angular momentum plays a significant role. Taking all these into account, we have determined the range of the particle's charge, angular momentum and energy of the particle for which the event horizon disappears. Our analysis shows that the WCCC can be violated in both extremal and non extremal KN MOG black hole, provided the particle's parameters are small and precisely adjusted. Crucially, prior work by [1] discussed the WCCC in KN spacetime without considering the modified gravity parameter {\alpha}. In contrast, our study shows that incorporating {\alpha} significantly enlarges the range of permissible parameters for the test particle, leading to the violation of the WCCC in both extremal and non extremal KN MOG black holes.

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Waqar Ahmad, Abdul Rehman Kashif. 2025-08-25. Testing the weak cosmic censorship conjecture via test particle induced overcharging/overspinning of Kerr Newman modified gravity black hole. https://arxiv.org/abs/2508.17665

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