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arXiv · 1303.4576

Perturbations of Kantowski-Sachs models

Michael Bradley·Mats Forsberg·Zoltán Keresztes·László Á. Gergely·Peter K. S. Dunsby
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Abstract

Perturbations of Kantowski-Sachs models with a positive cosmological constant are considered in a harmonic decomposition, in the framework of gauge invariant 1+3 and 1+1+2 covariant splits of spacetime. Scalar, vector and tensor modes are allowed, however they remain vorticity-free and of perfect fluid type. The dynamics is encompassed in six evolution equations for six harmonic coefficients.

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Michael Bradley, Mats Forsberg, Zoltán Keresztes, László Á. Gergely, Peter K. S. Dunsby. 2013-03-19. Perturbations of Kantowski-Sachs models. https://arxiv.org/abs/1303.4576

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