Speaker
Description
Dynamical dark energy (DDE) models have been proposed to address several observational tensions arising within the standard Lambda Cold Dark Matter scenario. Different DDE models, parameterized by different combinations of the local value of the equation-of-state parameter w0 and its time derivative wa, predict different maximal abundance of massive galaxies in the early Universe. We used the observed abundance of massive galaxies already in place at z~4-7 to constrain DDE models. To this aim we use three independent probes: (i) the observed stellar mass function at z~6 from the CANDELS survey; (ii) the estimated volume density of massive halos derived from the observation of massive, star-forming galaxies detected in the submillimeter range at z~4; (iii) the rareness of the most massive system detected at z~7 by the SPT survey (Marrone et al. 2018). I will show that the combination of these three probes exclude a sizable fraction of the DDE parameter space presently allowed (or even favored) by other existing probes.
