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arXiv · 2303.07358

Extremal Kerr black holes as amplifiers of new physics

Gary T. Horowitz·Maciej Kolanowski·Grant N. Remmen·Jorge E. Santos
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Abstract

We show that extremal Kerr black holes are sensitive probes of new physics. Stringy or quantum corrections to general relativity are expected to generate higher-curvature terms in the gravitational action. We show that in the presence of these terms, asymptotically flat extremal rotating black holes have curvature singularities on their horizon. Furthermore, near-extremal black holes can have large yet finite tidal forces for infalling observers. In addition, we consider five-dimensional extremal charged black holes and show that higher-curvature terms can have a large effect on the horizon geometry.

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Gary T. Horowitz, Maciej Kolanowski, Grant N. Remmen, Jorge E. Santos. 2023-03-13. Extremal Kerr black holes as amplifiers of new physics. https://doi.org/10.1103/physrevlett.131.091402

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