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arXiv · 2508.12657

Electric Penrose process in spherically symmetric regular black holes with and without a cosmological constant

Haowei Chen·Hengyu Xu·Yizhi Zhan·Shao-Jun Zhang
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Abstract

We investigate the electric Penrose process in Ay\'{o}n-Beato-Garc\'{i}a (ABG) black holes, both in the presence and absence of a cosmological constant, presenting, to the best of our knowledge, the first such analysis within the context of regular black holes. Our study systematically examines the effects of black hole charge and the cosmological constant on the formation of negative-energy states and the efficiency of energy extraction. Compared to Reissner-Nordstr\"{o}m (RN) black holes, ABG black holes exhibit a significantly larger negative-energy region, enabling the electric Penrose process to operate at larger distances from the event horizon and achieve higher energy extraction efficiency. This enhancement is particularly pronounced near the event horizon, where the performance gap widens with increasing black hole charge. Notably, even for astrophysically realistic values of charge and cosmological constant that approach vanishingly small values, distinct differences persist, yielding a maximum efficiency ratio of approximately $23/8$. These results suggest that, in realistic astrophysical scenarios, ABG black holes can accelerate charged particles more efficiently and serve as more powerful engines for energy extraction than their RN counterparts.

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Haowei Chen, Hengyu Xu, Yizhi Zhan, Shao-Jun Zhang. 2025-08-18. Electric Penrose process in spherically symmetric regular black holes with and without a cosmological constant. https://doi.org/10.1088/1361-6382%2Fae8e25

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