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arXiv · 0708.1812

1+1+2 gravitational perturbations on LRS class II space-times: Decoupling GEM tensor harmonic amplitudes

R. B. Burston
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Abstract

This paper considers gauge-invariant and covariant gravitational perturbations on arbitrary vacuum locally rotationally symmetric (LRS) class II space-times. Ultimately, we derive four decoupled equations governing four specific combinations of the gravito-electromagnetic (GEM) 2-tensor harmonic amplitudes. We use the gauge-invariant and covariant 1+1+2 formalism which Clarkson and Barrett developed for analysis of vacuum Schwarzschild perturbations. In particular we focus on the first-order 1+1+2 GEM system and use linear algebra techniques suitable for exploiting its structure. Consequently, we express the GEM system new 1+1+2 complex form by choosing new complex GEM tensors, which is conducive to decoupling. We then show how to derive a gauge-invariant and covariant decoupled equation governing a newly defined complex GEM 2-tensor. Finally, the GEM 2-tensor is expanded in terms of arbitrary tensor harmonics and linear algebra is used once again to decouple the system further into 4 real decoupled equations.

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R. B. Burston. 2007-08-14. 1+1+2 gravitational perturbations on LRS class II space-times: Decoupling GEM tensor harmonic amplitudes. https://doi.org/10.1088/0264-9381%2F25%2F7%2F075004

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