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arXiv · 2609.30990

Teukolsky Master Equation for a Kerr-like metric with Mass Quadrupole Moment

Pedro Gómez·Adrián Eduarte-Rojas·Francisco Frutos-Alfaro·Antonio Banichevich
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Abstract

The Teukolsky Master Equation (TME) is a powerful technique used to study perturbations of a spacetime with gravitational, electromagnetic, and neutrino components. The well-known Kerr metric is a suitable candidate for this formalism because it is a Petrov type D metric. However, the Kerr metric represents the exterior spacetime of a perfect sphere and only black holes are described using this metric. For another astrophysical object, such as fast-spinning neutron stars, the Kerr metric is not valid due to the rotation induced deformations to the gravitational source. The main goal of the present work is to show a TME for a Kerr-like metric (KL) with a mass quadrupole moment parameter $q$. This new parameter will represent deformations from a perfect sphere; therefore, KL is a better candidate to study perturbations surrounding spinning stars.

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Pedro Gómez, Adrián Eduarte-Rojas, Francisco Frutos-Alfaro, Antonio Banichevich. 2026-09-25. Teukolsky Master Equation for a Kerr-like metric with Mass Quadrupole Moment. https://arxiv.org/abs/2609.30990

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