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arXiv · gr-qc/0212046

Viscous cosmological models and accelerated Universes

G. M. Kremer·F. P. Devecchi
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Abstract

It is shown that a present acceleration with a past deceleration is a possible solution of the Friedmann equation by considering the Universe as a mixture of a scalar with a matter field and by including a non-equilibrium pressure term in the energy-momentum tensor. The dark energy density decays more slowly with respect to the time than the matter energy density does. The inclusion of the non-equilibrium pressure leads to a less pronounced decay of the matter field with a shorter period of past deceleration.

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G. M. Kremer, F. P. Devecchi. 2002-12-12. Viscous cosmological models and accelerated Universes. https://doi.org/10.1103/physrevd.67.047301

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