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The asymptotic regimes of tilted Bianchi II cosmologies

C. G. Hewitt·R. Bridson·J. Wainwright
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Abstract

In this paper we give, for the first time, a complete description of the dynamics of tilted spatially homogeneous cosmologies of Bianchi type II. The source is assumed to be a perfect fluid with equation of state $p = (γ-1) μ$, where $γ$ is a constant. We show that unless the perfect fluid is stiff, the tilt destabilizes the Kasner solutions, leading to a Mixmaster-like initial singularity, with the tilt being dynamically significant. At late times the tilt becomes dynamically negligible unless the equation of state parameter satisfies $γ> {10/7}$. We also find that the tilt does not destabilize the flat FL model, with the result that the presence of tilt increases the likelihood of intermediate isotropization.

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C. G. Hewitt, R. Bridson, J. Wainwright. 2000-08-15. The asymptotic regimes of tilted Bianchi II cosmologies. https://doi.org/10.1023/a%3A1002075902953

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