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arXiv · 2607.16581

Separating the linearized Einstein equations in Kerr

Jianwei Mei
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Abstract

A direct separation of the linearized Einstein equations in Kerr is presented. The trace of the perturbed metric is found to obey the spin-0 perturbation equation and so is irrelevant for the spin-2 perturbations. By combining the traceless condition, the Killing-Yano symmetry, a parity requirement, and the de Donder gauge condition, it has been found possible to reduce the linearized Einstein equations in Kerr to a manageable level, thereby enabling the direct separation of the equations and the derivation of a unique set of decoupled mode functions for the spin-2 perturbation of the Kerr black hole.

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Jianwei Mei. 2026-07-18. Separating the linearized Einstein equations in Kerr. https://arxiv.org/abs/2607.16581

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