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arXiv · 2510.26866

Third law of repetitive electric Penrose processes

Li Hu·Rong-Gen Cai·Shao-Jiang Wang
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Abstract

Recently, Ruffini et al. [Phys. Rev. Lett. 134 (2025) 8, 081403] pointed out that the repetitive Penrose process cannot drain the entire extractable energy of a Kerr black hole. In this Letter, we alternatively point out the charge of a Reissner-Nordstr\"{o}m black hole cannot drop down to exactly zero via the repetitive electric Penrose process that is terminated after a finite number of iterative steps, indicating a new thermodynamical third-law analog for the repetitive electric Penrose process.

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Li Hu, Rong-Gen Cai, Shao-Jiang Wang. 2025-10-30. Third law of repetitive electric Penrose processes. https://doi.org/10.1103/vlgc-y3qg

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