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arXiv · 2512.00108

Enhanced energy extraction via magnetic reconnection in Kerr-AdS spacetime

Abstract

In this paper, we study the energy extraction from Kerr-AdS black holes following the magnetic reconnection process. The parameter space regions that satisfy the energy extraction condition, as well as the efficiency and power of the extracted energy, are analyzed. The study shows that the presence of a negative cosmological constant extends the range of dominant reconnection radial locations where the energy extraction condition is met, and enables energy extraction even from black holes with relatively low spin. Furthermore, the influence of the negative cosmological constant on energy extraction is modulated by the extent of the dominant reconnection radial region: a more negative cosmological constant enhances the extracted energy, efficiency, and power, particularly for smaller dominant reconnection radii. These results demonstrate that the energy extraction from Kerr-AdS black holes is more favorable than that from their asymptotically flat counterparts. Our results highlight the crucial role of the cosmological constant in energy extraction via magnetic reconnection.

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Bo Zhao, Chao-Hui Wang, Shao-Wen Wei. 2025-11-27. Enhanced energy extraction via magnetic reconnection in Kerr-AdS spacetime. https://arxiv.org/abs/2512.00108

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