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arXiv · 2201.02220

Black Hole Superradiance in Dynamical Chern-Simons Gravity

Stephon Alexander·Gregory Gabadadze·Leah Jenks·Nicolás Yunes
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Abstract

Black hole superradiance provides a window into the dynamics of light scalar fields and their interactions close to a rotating black hole. Due to the rotation of the black hole, the amplitude of the scalar field becomes magnified, leading to a "black hole bomb" effect. Recent work has demonstrated that rotating black holes in dynamical Chern-Simons gravity possess unique structures, the "Chern-Simons caps," which may influence the behavior of matter near the black hole. Motivated by the presence of these caps, we study superradiance in dynamical Chern-Simons gravity in the context of a slowly rotating black hole. We find that additional modes are excited and contribute to the superradiance beyond what is expected for a Kerr black hole. Studying the superradiant spectrum of perturbations, we find that the Chern-Simons contributions give rise to small corrections to the angular dependence of the resulting scalar cloud. Finally, we comment on potential observable consequences and future avenues for investigation.

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Stephon Alexander, Gregory Gabadadze, Leah Jenks, Nicolás Yunes. 2022-01-06. Black Hole Superradiance in Dynamical Chern-Simons Gravity. https://doi.org/10.1103/physrevd.107.084016

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