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arXiv · 1401.6826

Penrose process in charged axion-dilaton coupled black hole

Chandrima Ganguly·Soumitra SenGupta
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Abstract

Using the Newman-Janis method to construct the axion-dilaton coupled charged rotating black holes, we show that the energy extraction from such black holes via Penrose process takes place from the axion/Kalb-Ramond field energy responsible for rendering the angular momentum to the black hole. Determining the explicit form for the Kalb-Ramond field strength, which is argued to be equivalent to spacetime torsion, we demonstrate that at the end of the energy extraction process, the spacetime becomes torsion free with a spherically symmetric non-rotating black hole remnant.

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Chandrima Ganguly, Soumitra SenGupta. 2014-01-28. Penrose process in charged axion-dilaton coupled black hole. https://arxiv.org/abs/1401.6826

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