Implications of an Extended Dark Energy Model with Massive Neutrinos

Abstract

Recently there have been reports of finding a lower bound on the neutrino mass parameter (Σmν) when using the Atacama Cosmology Telescope (ACT) and SPTpol data; however, these bounds on the Σmν are still weaker for most cases around the 1σ level. In this context, here in this work, we study the consequences of using an enlarged four parameter dynamical dark energy equation of state on the neutrino mass parameter as well as on the Hubble and S8 tensions. The four parameter dark energy equation of state incorporates a generic nonlinear monotonic evolution of the dark energy equation of state, where the four parameters are the early and the present value of the equation of state, the transition scale factor, and the sharpness of the transition. We report that with lensingmarginalized Planck + BAO + Pantheon and prior on absolute magnitude MB, and KIDS/Viking S8 prior, the model favors a nonzero value for the neutrino mass parameter at most at the 1σ level (S =n - + m 0.1847 0.165 0.0698 eV). In this case this model also brings down the Hubble tension to a 2.5σ level and the S8 tension to a ∼1.5σ level. This model also provides tighter constraints on the value of the dark energy equation of state at present epoch w0 ( = - - + w0 0.9901 0.0766 0.0561) in comparison to the Chevalier-Polarski and Linder-like parameterization.