mgr Aleksander Kozak

Inflationary potentials from F(R) gravity in a unified hybrid metric-Palatini approach

A class of scalar-tensor theories that unify metric, Palatini and hybrid metric-Palatini gravitational actions with nonminimal interaction is investigated from the point of view of their consistency with generalized conformal transformations. It is known that such theory can be represented on shell by a purely metric scalar-tensor theory. This extends the formalism previously introduced in our last paper [1]. Exploiting properties of the Legendre transformation, we relate some viable inflationary potentials with F(R)-gravitational Lagrangians by solving corresponding Clairaut's equation. Then for given potential function various gravitational scenarios are discussed within a metric, Palatini, as well as a hybrid metric-Palatini formulations. [1] A. Kozak and A. Borowiec, "Palatini frames in scalar-tensor theories of gravity", Eur.Phys.J. C79 (2019) no.4, 335