Bouncing cosmologies with dark matter and dark energy
  We review matter bounce scenarios where the matter content is dark matter and
dark energy. These cosmologies predict a nearly scale-invariant power spectrum
with a slightly red tilt for scalar perturbations and a small tensor-to-scalar
ratio. Importantly, these models predict a positive running of the scalar
index, contrary to the predictions of the simplest inflationary and ekpyrotic
models, and hence could potentially be falsified by future observations. We
also review how bouncing cosmological space-times can arise in theories where
either the Einstein equations are modified or where matter fields that violate
the null energy condition are included.
