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arXiv · gr-qc/0505108

Inhomogeneous perturbations of plane-wave spacetimes

Sigbjorn Hervik·Alan Coley
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Abstract

Recently it was shown that the exact cosmological solutions known as the vacuum plane-wave solutions are late-time attractors for an open set of the spatially homogeneous Bianchi universes containing a non-inflationary $γ$-law perfect fluid. In this paper we study inhomogeneous perturbations of these plane-wave spacetimes. By using expansion-normalised scale-invariant variables we show that these solutions are unstable to generic inhomogeneous perturbations. The crucial observation for establishing this result is a divergence of the expansion-normalised frame variables which ultimately leads to unstable modes.

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Sigbjorn Hervik, Alan Coley. 2005-07-08. Inhomogeneous perturbations of plane-wave spacetimes. https://doi.org/10.1088/0264-9381%2F22%2F17%2F002

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