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arXiv · 2609.33661

Perturbations of Kerr-Newman black holes: separation and mode stability

Peter Hintz
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Abstract

We study linearized perturbations of the subextremal Kerr-Newman black hole solution of the Einstein-Maxwell equations. We show how to overcome what Chandrasekhar called the "apparent indissolubility of the coupling between the spin-1 and spin-2 fields" by using a matrix integrating factor for suitably transformed first-order systems that describe the radiative degrees of freedom. For the radial ODEs obtained after angular separation, we prove mode stability on the real axis, i.e., the absence of quasinormal modes with real frequencies, using a Whiting-type transform.

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Peter Hintz. 2026-09-27. Perturbations of Kerr-Newman black holes: separation and mode stability. https://arxiv.org/abs/2609.33661

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