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-to-vary 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.