Dark matter from dark energy-baryonic matter couplings
  We present a scenario in which a scalar field dark energy is coupled to the
trace of the energy momentum tensor of the baryonic matter fields. In the
slow-roll regime, this interaction could give rise to the cosmological features
of dark matter. We work out the cosmological background solutions and fit the
parameters of the model using the Union 2 supernovae data set. Then, we develop
the cosmological perturbations up to linear order, and we find that the
perturbed variables have an acceptable behavior, in particular the density
contrast of baryonic matter grows similar to that in the $\Lambda$CDM model for
a suitable choice of the strength parameter of the coupling.
