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Quasinormal modes of Kerr-Newman black holes: coupling of electromagnetic and gravitational perturbations

Emanuele Berti·Kostas D. Kokkotas
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Abstract

We compute numerically the quasinormal modes of Kerr-Newman black holes in the scalar case, for which the perturbation equations are separable. Then we study different approximations to decouple electromagnetic and gravitational perturbations of the Kerr-Newman metric, computing the corresponding quasinormal modes. Our results suggest that the Teukolsky-like equation derived by Dudley and Finley gives a good approximation to the dynamics of a rotating charged black hole for Q<M/2. Though insufficient to deal with Kerr-Newman based models of elementary particles, the Dudley-Finley equation should be adequate for astrophysical applications.

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Emanuele Berti, Kostas D. Kokkotas. 2005-05-29. Quasinormal modes of Kerr-Newman black holes: coupling of electromagnetic and gravitational perturbations. https://doi.org/10.1103/physrevd.71.124008

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