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arXiv · 0802.3629

Bianchi models with vorticity: The type III bifurcation

A. Coley·S. Hervik
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Abstract

We study the late-time behaviour of tilted perfect fluid Bianchi type III models using a dynamical systems approach. We consider models with dust, and perfect fluids stiffer than dust, and eludicate the late-time behaviour by studying the centre manifold which dominates the behaviour of the model at late times. In the dust case, this centre manifold is 3-dimensional and can be considered as a double bifurcation as the 2 parameters ($h$ and $γ$) of the type VI$_h$ model are varied. We calculate the decay rates and show that for dust or stiffer the models approach a vacuum spacetime, however, it does so rather slowly: $ρ/H^2\sim 1/\ln t$.

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A. Coley, S. Hervik. 2008-02-25. Bianchi models with vorticity: The type III bifurcation. https://doi.org/10.1088/0264-9381%2F25%2F19%2F198001

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