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arXiv · 2512.17369

Generalized Kerr-Schild gauge

Enrique Alvarez·Jesus Anero
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Abstract

The Kerr-Schild gauge is generalized to the case that the vector generating the deformation is not null. Contrary to naive expectations, this vector generates a finite expansion for the curvature tensor. We prove a theorem on the conditions for the deformed metric being Ricci flat, namely that the deformation vector must be irrotational (then geodesic) in the background spacetime.

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Enrique Alvarez, Jesus Anero. 2026-04-03. Generalized Kerr-Schild gauge. https://arxiv.org/abs/2512.17369

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