Revealing the effects of curvature on the cosmological models

In this paper, we consider the effects of adding curvature in extended cosmologies involving a free-tovary neutrino sector and different parametrizations of dark energy (DE). We make use of the Planck 2018 cosmic microwave background temperature and polarization data, baryon acoustic oscillations and Pantheon type Ia supernovae data. Our main result is that a nonflat Universe cannot be discarded in light of the current astronomical data, because we find an indication for a closed Universe in most of the DE cosmologies explored in this work. On the other hand, forcing the Universe to be flat can significantly bias the constraints on the equation of state of the DE component and its dynamical nature.

Automated summary

In this study, the effects of introducing curvature in extended cosmologies with a varying neutrino sector and different parametrizations of dark energy are considered. The Planck 2018 data, including cosmic microwave background temperature and polarization data, baryon acoustic oscillations, and Pantheon type Ia supernovae data are utilized. The main finding is that a nonflat Universe cannot be ruled out based on the current astronomical data, as there is evidence for a closed Universe in most of the explored dark energy cosmologies. However, enforcing a flat Universe can significantly bias the constraints on the equation of state of the dark energy component and its dynamical nature.