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arXiv · 2109.02607

Scalar and Gravitational Transient "Hair" for Near-Extremal Black Holes

Kevin Gonzalez-Quesada·Subir Sabharwal·Gaurav Khanna
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Abstract

We study the existence and nature of Aretakis "hair" and its potentially observable imprint at a finite distance from the horizon (Ori-coefficient) in near-extremal black hole backgrounds. Specifically, we consider the time evolution of horizon penetrating scalar and gravitational perturbations with compact support on near-extremal Reissner-Nordstrom (NERN) and Kerr (NEK). We do this by numerically solving the Teukolsky equation and determining the Aretakis charge values on the horizon and at a finite distance from the black hole. We demonstrate that these values are no longer strictly conserved in the non-extremal case; however, their decay rate can be arbitrarily slow as the black hole approaches extremality allowing for the possibility of their observation as a transient hair.

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Kevin Gonzalez-Quesada, Subir Sabharwal, Gaurav Khanna. 2021-09-06. Scalar and Gravitational Transient "Hair" for Near-Extremal Black Holes. https://doi.org/10.1103/physrevd.105.044032

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