Cosmological constraints on alternative model to Chaplygin fluid revisited

Abstract

In this work we explore an alternative phenomenological model to Chaplygin gas proposed by Hova et al. (Int J Mod Phys D 26:1750178, 2017), consisting on a modification of a perfect fluid, to explain the dynamics of dark matter and dark energy at cosmological scales immerse in a flat or curved universe. Adopting properties similar to a Chaplygin gas, the proposed model is a mixture of dark matter and dark energy components parameterized by only one free parameter denoted as μ. We focus on contrasting this model with the most recent cosmological observations of Type Ia supernovae and Hubble parameter measurements. Our joint analysis yields a value μ=0.843-0.015+0.014 (0.822-0.024+0.022) for a flat (curved) universe. Furthermore, with these constraints we also estimate the deceleration parameter today q0=-0.67±0.02(-0.51±0.07), the acceleration-deceleration transition redshift zt=0.57±0.04(0.50±0.06), and the universe age tA=13.108-0.260+0.270×(12.314-0.430+0.590)Gyrs. We also report a best value of Ωk=0.183-0.079+0.073 consistent at 3 σ with the one reported by Planck Collaboration. Our analysis confirm the results by Hova et al. this Chaplygin gas-like is a plausible alternative to explain the nature of the dark sector of the universe.