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Axial perturbations of general spherically symmetric spacetimes

Max Karlovini
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Abstract

The aim of this paper is to present a governing equation for first order axial metric perturbations of general, not necessarily static, spherically symmetric spacetimes. Under the non-restrictive assumption of axisymmetric perturbations, the governing equation is shown to be a two-dimensional wave equation where the wave function serves as a twist potential for the axisymmetry generating Killing vector. This wave equation can be written in a form which is formally a very simple generalization of the Regge-Wheeler equation governing the axial perturbations of a Schwarzschild black hole, but in general the equation is accompanied by a source term related to matter perturbations. The case of a viscous fluid is studied in particular detail.

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Max Karlovini. 2002-03-28. Axial perturbations of general spherically symmetric spacetimes. https://doi.org/10.1088/0264-9381%2F19%2F8%2F305

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