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The Asymptotic Behaviour of Tilted Bianchi type VI$_0$ Universes

Sigbjorn Hervik
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Abstract

We study the asymptotic behaviour of the Bianchi type VI$_0$ universes with a tilted $γ$-law perfect fluid. The late-time attractors are found for the full 7-dimensional state space and for several interesting invariant subspaces. In particular, it is found that for the particular value of the equation of state parameter, $γ=6/5$, there exists a bifurcation line which signals a transition of stability between a non-tilted equilibrium point to an extremely tilted equilibrium point. The initial singular regime is also discussed and we argue that the initial behaviour is chaotic for $γ<2$.

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Sigbjorn Hervik. 2004-03-09. The Asymptotic Behaviour of Tilted Bianchi type VI$_0$ Universes. https://doi.org/10.1088/0264-9381%2F21%2F9%2F007

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