A General Supergravity Formalism for a Naturally Flat Inflaton Potential

Abstract

A globally supersymmetric model of inflation will not work in a generic supergravity theory because the higher order, nonrenormalisable supergravity corrections destroy the flatness of the inflaton's potential. In this talk I derive a form for the Kahler potential which eliminates these corrections if $ W = \partial W / \partial φ= ψ= 0 $ during inflation (where $W$ is the superpotential, the inflaton is contained in $φ$, and $ \partial W / \partial ψ\neq 0 $). I then point out that Kahler potentials of the required form often occur in superstrings and that the target space duality symmetries of superstrings often contain R-parities which would make $ W = \partial W / \partial φ= 0 $ automatic for $ψ= 0$.