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arXiv · 1202.1407

Singularities in cosmologies with interacting fluids

Spiros Cotsakis·Georgia Kittou
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Abstract

We study the dynamics near finite-time singularities of flat isotropic universes filled with two interacting but otherwise arbitrary perfect fluids. The overall dynamical picture reveals a variety of asymptotic solutions valid locally around the spacetime singularity. We find the attractor of all solutions with standard decay, and for `phantom' matter asymptotically at early times. We give a number of special asymptotic solutions describing universes collapsing to zero size and others ending at a big rip singularity. We also find a very complicated singularity corresponding with a logarithmic branch point that resembles of cyclic universe, and give an asymptotic local series representation of the general solution in the neighborhood of infinity.

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Spiros Cotsakis, Georgia Kittou. 2012-04-24. Singularities in cosmologies with interacting fluids. https://doi.org/10.1016/j.physletb.2012.04.057

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