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arXiv · 2103.03611

Black Hole Superradiance in the Presence of Lorentz Symmetry Violation

Mohsen Khodadi
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Abstract

In this paper we consider the massive scalar perturbation on the top of a small spinning-like black hole in context of Einstein-bumblebee modified gravity in order to probe the role of spontaneous Lorentz symmetry breaking on the superradiance scattering and corresponding instability. We show that at the low-frequency limit of the scalar wave the superradiance scattering will be enhanced with the Lorentz-violating parameter $\alpha<0$ and will be weakened with $\alpha>0$. Moreover, by addressing the black hole bomb issue, we extract an improved bound in the instability regime indicating that $\alpha<0$ increases the parameter space of the scalar field instability, while $\alpha>0$ decreases it.

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Mohsen Khodadi. 2021-03-05. Black Hole Superradiance in the Presence of Lorentz Symmetry Violation. https://doi.org/10.1103/physrevd.103.064051

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