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Irreversible processes and the accelerated-decelerated phases of the Universe

G. M. Kremer·M. C. N. Teixeira da Silva
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Abstract

A model for the Universe is proposed where it is considered as a mixture of scalar and matter fields. The particle production is due to an irreversible transfer of energy from the gravitational field to the matter field and represented by a non-equilibrium pressure. This model can simulate three distinct periods of the Universe: (a) an accelerated epoch where the energy density of the scalar field prevails over the matter field, (b) a past decelerated period where the energy density of the matter field becomes more predominant than the scalar energy density, and (c) a present acceleration phase where the scalar energy density overcomes the energy density of the matter field.

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G. M. Kremer, M. C. N. Teixeira da Silva. 2004-04-01. Irreversible processes and the accelerated-decelerated phases of the Universe. https://doi.org/10.1590/s0103-97332004000600012

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