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Love numbers for extremal Kerr black holes

Malcolm Perry1,2,3,* and Maria J. Rodriguez4,5,6,†

  • *Contact author: malcolm@damtp.cam.ac.uk
  • †Contact author: maria.rodriguez@gmail.com
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Phys. Rev. D 112, 126004 – Published 3 December, 2025

DOI: https://doi.org/10.1103/s5vk-vdg1

Abstract

We perform a detailed study of the gravitational tidal Love numbers of extremal zero-temperature Kerr black holes. These coefficients are finite and exhibit the dissipative nature of these maximally spinning black holes. Upon considering the dynamical behavior of the tidal deformations of the extremal Kerr black holes, we provide explicit expressions of the Love numbers at low frequencies. Their calculation is simplified to specific formulas, which are directly derived using the Leaver–Mano-Suzuki-Takasugi method.

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Phys. Rev. D 112, 126004– Published 3 December, 2025
  • Received 30 June 2025
  • Accepted 20 October 2025
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