We discuss the possible consistency of the recently discovered Type Ia supernovae at z > 1 with models in which dark energy is strongly coupled to a significant fraction of dark matter , and in which an ( asymptotic ) accelerated phase exists where dark matter and dark energy scale in the same way .
Such a coupling has been suggested for a possible solution of the coincidence problem , and is also motivated by string cosmology models of “ late time ” dilaton interactions .
Our analysis shows that , for coupled dark energy models , the recent data are still consistent with acceleration starting as early as at z = 3 ( to within 90 % c.l .
) , although at the price of a large “ non-universality ” of the dark energy coupling to different matter fields .
Also , as opposed to uncoupled models which seem to prefer a “ phantom ” dark energy , we find that a large amount of coupled dark matter is compatible with present data only if the dark energy field has a conventional equation of state w > -1 .