DBI models for the unification of dark matter and dark energy
  We propose a model based on a DBI action for the unification of dark matter
and dark energy. This is supported by the results of the study of its
background behavior at early and late times, and reinforced by the analysis of
the evolution of perturbations. We also perform a Bayesian analysis to set
observational constraints on the parameters of the model using type Ia SN, CMB
shift and BAO data. Finally, to complete the study we investigate its
kinematics aspects, such as the effective equation of state parameter,
acceleration parameter and transition redshift. Particularizing those
parameters for the best fit one appreciates that an effective phantom is
preferred.
