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arXiv · 0905.0672

Cosmology with interaction in the dark sector

F. E. M. Costa·E. M. Barboza Jr.·J. S. Alcaniz
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Abstract

Unless some unknown symmetry in Nature prevents or suppresses a non-minimal coupling in the dark sector, the dark energy field may interact with the pressureless component of dark matter. In this paper, we investigate some cosmological consequences of a general model of interacting dark matter-dark energy characterized by a dimensionless parameter $\epsilon$. We derive a coupled scalar field version for this general class of scenarios and carry out a joint statistical analysis involving SNe Ia data ({Legacy} and {Constitution} sets), measurements of baryon acoustic oscillation peak at $z = 0.20$ (2dFGRS) and $z = 0.35$ (SDSS), and measurements of the Hubble evolution $H(z)$. For the specific case of vacuum decay ($w = -1$), we find that, although physically forbidden, a transfer of energy from dark matter to dark energy is favored by the data.

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F. E. M. Costa, E. M. Barboza Jr., J. S. Alcaniz. 2009-05-05. Cosmology with interaction in the dark sector. https://doi.org/10.1103/physrevd.79.127302

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