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arXiv · 1804.03656

Cosmological singularities and analytical solutions in varying vacuum cosmologies

S. Basilakos·A. Paliathanasis·J. D. Barrow·G. Papagiannopoulos
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Abstract

We investigate the dynamical features of a large family of running vacuum cosmologies for which $Λ$ evolves as a polynomial in the Hubble parameter. Specifically, using the critical point analysis we study the existence and the stability of singular solutions which describe de-Sitter, radiation and matter dominated eras. We find several classes of $Λ(H)$ cosmologies for which new analytical solutions are given in terms of Laurent expansions. Finally, we show that the Milne universe and the $R_{h}=ct$ model can be seen as perturbations around a specific $Λ(H)$ model, but this model is unstable.

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S. Basilakos, A. Paliathanasis, J. D. Barrow, G. Papagiannopoulos. 2018-08-07. Cosmological singularities and analytical solutions in varying vacuum cosmologies. https://doi.org/10.1140/epjc%2Fs10052-018-6139-8

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