On the dark contents of the Universe: A Euclid survey approach
  In this work we study the consequences of allowing non pressureless dark
matter when determining dark energy constraints. We show that present-day dark
energy constraints from low-redshift probes are extremely degraded when
allowing this dark matter variation. However, adding the cosmic microwave
background (CMB) we can recover the $w_{DM} = 0$ case constraints. We also show
that with the future Euclid redshift survey we expect to largely improve these
constraints; but, without the complementary information of the CMB, there is
still a strong degeneracy between dark energy and dark matter equation of state
parameters.
