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arXiv · 2205.02628

Is there a trade-off relation between efficiency and power in a collisional Penrose process in an extreme Reissner-Nordström spacetime?

Naoki Tsukamoto
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Abstract

We investigate the power of a collisional Penrose process with an unbound energy extraction from an extreme Reissner-Nordström black hole. This process takes infinite time in a time coordinate at a constant radial coordinate outside of the black hole. For black holes as a power plant, the power of the process for an observer far away from the black hole can be useful. We define the power as energy gain from the extreme Reissner-Nordström black hole divided by the time interval of the process in a coordinate time; we estimate the upper bound of the power in a near-horizon limit, while the efficiency of the process can be arbitrary large in that limit. Thus, we conclude that there is no trade-off relation between the efficiency and power in the collisional Penrose process in extreme Reissner-Nordström spacetime.

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Naoki Tsukamoto. 2022-05-25. Is there a trade-off relation between efficiency and power in a collisional Penrose process in an extreme Reissner-Nordström spacetime?. https://doi.org/10.1103/physrevd.105.104065

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