Scaling cosmology with variable darkenergy equation of state
Abstract
Interactions between dark matter and dark energy which result in a powerlaw behavior (with respect to the cosmic scale factor) of the ratio between the energy densities of the dark components (thus generalizing the ΛCDM model) have been considered as an attempt to alleviate the cosmic coincidence problem phenomenologically. We generalize this approach by allowing for a variable equation of state for the dark energy within the CPLparametrization. Based on analytic solutions for the Hubble rate and using the Constitution and Union2 SNIa sets, we present a statistical analysis and classify different interacting and noninteracting models according to the Akaike (AIC) and the Bayesian (BIC) information criteria. We do not find noticeable evidence for an alleviation of the coincidence problem with the mentioned type of interaction.
 Publication:

Journal of Cosmology and Astroparticle Physics
 Pub Date:
 June 2012
 DOI:
 10.1088/14757516/2012/06/024
 arXiv:
 arXiv:1201.0850
 Bibcode:
 2012JCAP...06..024C
 Keywords:

 Astrophysics  Cosmology and Extragalactic Astrophysics;
 General Relativity and Quantum Cosmology;
 High Energy Physics  Theory
 EPrint:
 21 pages, 11 figures, 11 tables, discussion improved