Emergent Dark Energy, neutrinos and cosmological tensions

Abstract

The Phenomenologically Emergent Dark Energy model, a dark energy model with the same number of free parameters as the flat $\Lambda$CDM, has been proposed as a working example of a minimal model which can avoid the current cosmological tensions. A straightforward question is whether or not the inclusion of massive neutrinos and extra relativistic species may spoil such an appealing phenomenological alternative. We present the bounds on $M_{\nu }$ and $N_{\mathrm{eff}}$ and comment on the long standing $H_0$ and ${\sigma }_8$ tensions within this cosmological framework with a wealth of cosmological observations. Interestingly, we find, at $95\%$ confidence level, and with the most complete set of cosmological observations, $M_{\nu }\sim 0.21_{-0.14}^{+0.15}$ eV and $N_{\mathrm{eff}}=3.03\pm 0.32$ i.e. an indication for a non-zero neutrino mass with a significance above $2\sigma$. The well known Hubble constant tension is considerably easened, with a significance always below the $2\sigma$ level.

12 pages, 6 tables and 3 figures. Title has been changed; published version in Physics of the Dark Universe