Cosmology with interaction in the dark sector
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 ε. 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.