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An analysis of the shear dynamics in Bianchi I cosmologies with $R^n$-gravity

Jannie A. Leach·Peter K. S. Dunsby·Sante Carloni
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Abstract

We consider the case of $R^n$-gravity and perform a detailed analysis of the dynamics in Bianchi I cosmologies which exhibit {\it local rotational symmetry} (LRS). We find exact solutions and study their behaviour and stability in terms of the values of the parameter $n$. In particular, we found a set of cosmic histories in which the universe is initially isotropic, then develops shear anisotropies which approaches a constant value.

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Jannie A. Leach, Peter K. S. Dunsby, Sante Carloni. 2007-02-23. An analysis of the shear dynamics in Bianchi I cosmologies with $R^n$-gravity. https://arxiv.org/abs/gr-qc/0702122

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