Unitarizing non-Minimal Inflation via a Linear Contribution to the Frame Function

Abstract

We show that non-minimal inflation, based on the phi^4 potential, may be rendered unitarity conserving and compatible with the Planck results for 4.6x10^(-3)<~r21=c2R/c1R^2<~1, if we introduce a linear contribution (c1R phi) to the frame function which takes the form fR=1+c1R phi+c2R phi^2. Supersymmetrization of this model can be achieved by considering two gauge singlet superfields and combining a linear-quadratic superpotential term, with a class of logarithmic or semi-logarithmic Kaehler potentials with prefactor for the logarithms including the inflaton field -(2n+3) or -2(n+1) where -0.01<~ n<~0.013.