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arXiv · 2112.06056

Energy Extraction, or Lack Thereof

Nishanth Gudapati
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Abstract

The problem of stability of rotating black holes is the subject of a long standing research program since the 1960s and remains an unresolved problem in general relativity. A major obstacle in the black hole stability problem is that the energy of waves propagating through rotating black holes spacetimes is not necessarily positive-definite, due to the so called ergo-region. This is a serious complication that limits the efficacy of most mathematical techniques. In this Letter, we report that, despite the ergo-region, there exists a positive-definite \emph{total energy} for axisymmetric Maxwell, gravitational and electrovacuum perturbations of Kerr and Kerr-Newman black hole spacetimes.

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Nishanth Gudapati. 2021-12-11. Energy Extraction, or Lack Thereof. https://doi.org/10.1038/s41598-023-37451-z

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