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arXiv · 2104.11376

Charged black-bounce spacetimes

Edgardo Franzin·Stefano Liberati·Jacopo Mazza·Alex Simpson·Matt Visser
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Abstract

Given the recent development of rotating black-bounce-Kerr spacetimes, for both theoretical and observational purposes it becomes interesting to see whether it might be possible to construct black-bounce variants of the entire Kerr-Newman family. Specifically, herein we shall consider black-bounce-Reissner-Nordstr\"om and black-bounce-Kerr-Newman spacetimes as particularly simple and clean everywhere-regular black hole "mimickers" that deviate from the Kerr-Newman family in a precisely controlled and minimal manner, and smoothly interpolate between regular black holes and traversable wormholes. While observationally the electric charges on astrophysical black holes are likely to be extremely low, $|Q|/m \ll 1$, introducing any non-zero electric charge has a significant theoretical impact. In particular, we verify the existence of a Killing tensor (and associated Carter-like constant) but without the full Killing tower of principal tensor and Killing-Yano tensor, also we discuss how, assuming general relativity, the black-bounce-Kerr-Newman solution requires an interesting, non-trivial matter/energy content.

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Edgardo Franzin, Stefano Liberati, Jacopo Mazza, Alex Simpson, Matt Visser. 2021-04-23. Charged black-bounce spacetimes. https://doi.org/10.1088/1475-7516/2021/07/036

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