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arXiv · 2512.18512

Ergosphere Dynamics and Rotational Energy Extraction in Bumblebee Kerr-Newman-AdS Black Holes

H. Hassanabadi·A. Guvendi·F. Kafikang·T. Sathiyaraj·S. Zare
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Abstract

We present a comprehensive analysis of the thermodynamic and optical properties of the Bumblebee Kerr-Newman-Anti-de Sitter (AdS) black hole, a rotating and charged configuration arising in Lorentz symmetry-violating (LSV) gravity. The influence of the black hole parameters on the horizon structure, thermodynamic stability, and geometric deformation of spacetime is systematically investigated. Explicit expressions for the Hawking temperature, entropy, and heat capacity are derived, revealing the formation of black hole remnants and extended stability phases induced by Lorentz symmetry-violating (LSV) effects. The sparsity of Hawking radiation is quantified, showing that Lorentz violation suppresses the continuum limit and produces a more discrete, less thermal emission spectrum. A detailed analysis of null geodesics is performed to determine the photon region and shadow morphology, indicating that increasing l and Q compresses and distorts the shadow boundary, while rotation diminishes its overall size. The ergosphere geometry is analyzed in detail, showing that increases in a, l, and Q not only enlarge and distort the ergoregion but also intensify frame-dragging, thereby maximizing the efficiency of energy extraction via the Penrose process. These results reveal clear and potentially observable deviations from standard Kerr-Newman-AdS predictions, providing a powerful new avenue to probe Lorentz symmetry breaking and test the fundamental structure of gravity in extreme strong field regimes.

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H. Hassanabadi, A. Guvendi, F. Kafikang, T. Sathiyaraj, S. Zare. 2025-12-20. Ergosphere Dynamics and Rotational Energy Extraction in Bumblebee Kerr-Newman-AdS Black Holes. https://arxiv.org/abs/2512.18512

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