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arXiv · 0908.4251

Cosmological consequences of a possible $Λ$-dark matter interaction

F. E. M. Costa·J. S. Alcaniz
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Abstract

We propose a general class of interacting models in which the interaction between the CDM component and $Λ$ is parameterized by an arbitrary function of the cosmic scale factor $ε(a)$. Differently from other dynamical $Λ$ scenarios in which the final stage of cosmic expansion is a de Sitter phase, we find solutions of transient acceleration, in which the $Λ$-dark matter interaction will drive the Universe to a new dark matter-dominated era in the future. We investigate some cosmological consequences of this model and discuss some constraints on its parameters from current SNe Ia, BAO, CMB and $H_0$ data.

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F. E. M. Costa, J. S. Alcaniz. 2009-08-28. Cosmological consequences of a possible $Λ$-dark matter interaction. https://doi.org/10.1103/physrevd.81.043506

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