A parametric model for dark energy
Abstract
Determining the mechanism behind the current cosmic acceleration constitutes a major question nowadays in theoretical physics. If the dark energy route is taken, this problem may potentially bring to light new insights not only in cosmology but also in high energy physics theories. Following this approach, we explore in this Letter some cosmological consequences of a new timedependent parameterization for the dark energy equation of state (EoS), which is a well behaved function of the redshift z over the entire cosmological evolution, i.e., z∈[1,∞). This parameterization allows us to divide the parametric plane (w_{},w_{}) in defined regions associated to distinct classes of dark energy models that can be confirmed or excluded from a confrontation with current observational data. By assuming a flat universe, a statistical analysis involving the most recent observations from type Ia supernovae, baryon acoustic oscillation peak, Cosmic Microwave Background shift parameter and Hubble evolution H(z) is performed to check the observational viability of the EoS parameterization here proposed.
 Publication:

Physics Letters B
 Pub Date:
 September 2008
 DOI:
 10.1016/j.physletb.2008.08.012
 arXiv:
 arXiv:0805.1713
 Bibcode:
 2008PhLB..666..415B
 Keywords:

 98.80.Cq;
 Particletheory and fieldtheory models of the early Universe;
 Astrophysics
 EPrint:
 6 pages, 3 figures, LaTeX