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arXiv · 1705.04602

Anisotropic multiple bounce models

Anna Paula Bacalhau·Patrick Peter·Sandro D. P. Vitenti
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Abstract

We analyze the Galileon ghost condensate implementation of a bouncing cosmological model in the presence of a non negligible anisotropic stress. We exhibit its structure, which we find to be far richer than previously thought. In particular, even restricting attention to a single set of underlying microscopic parameters, we obtain, numerically, many qualitatively different regimes: depending on the initial conditions on the scalar field leading the dynamics of the universe, the contraction phase can evolve directly towards a singularity, avoid it by bouncing once, or even bounce many times before settling into an ever-expanding phase. We clarify the behavior of the anisotropies in these various situations.

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Anna Paula Bacalhau, Patrick Peter, Sandro D. P. Vitenti. 2017-05-11. Anisotropic multiple bounce models. https://doi.org/10.1103/physrevd.96.023517

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