Non-Minimally Gravity-Coupled Inflationary Models

Understand

We consider the non-supersymmetric models of chaotic (driven by a quadratic potential) and hybrid inflation, taking into account the minimal possible radiative corrections to the inflationary potential.

• We show that two simple coupling functions f(sigma) (with a parameter ck involved) between the inflaton field, sigma, and the Ricci scalar curvature ensure, for sub-Planckian values of the inflaton field, observationally acceptable values for the spectral index, ns, and sufficient reheating after inflation.
• In the case of chaotic inflation we consider two models with large ck's resulting to ns=0.955 or 0.967 and tensor-to-scalar ratio r=0.2 or 0.003, respectively.
• In the case of hybrid inflation, the selected f(sigma) assists us to obtain hilltop-type inflation.