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Shear dynamics in Bianchi I cosmologies with R^n-gravity

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

We give the equations governing the shear evolution in Bianchi spacetimes for general f(R)-theories of gravity. We consider the case of R^n-gravity and perform a detailed analysis of the dynamics in Bianchi I cosmologies which exhibit local rotational symmetry. 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, Sante Carloni, Peter K S Dunsby. 2006-06-23. Shear dynamics in Bianchi I cosmologies with R^n-gravity. https://doi.org/10.1088/0264-9381%2F23%2F15%2F011

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