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arXiv · gr-qc/9907016

Cosmological models with dynamical lambda in scalar-tensor theories

L. M. Diaz-Rivera·L. O. Pimentel
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Abstract

In the context of a family os scalar-tensor theories with a dynamical $Λ$, that is a binomial on the scalar field, the cosmological equations are considered. A general barotropic state equation $p=(γ-1)ρ$, for a perfect fluid is used for the matter content of the Universe. Some Friedmann- Robertson-Walker exact solutions are found, they have scale factor wich shows exponential or power law dependence on time. For some models the singularity can be avoided. Cosmological parameters as $Ω_m$, $Ω_Λ$, $q_0$ and $t_0$ are obtained and compared with observational data.

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L. M. Diaz-Rivera, L. O. Pimentel. 1999-11-11. Cosmological models with dynamical lambda in scalar-tensor theories. https://doi.org/10.1103/physrevd.60.123501

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