Inflation with large supergravity corrections

TL;DR

This paper demonstrates that within the minimal supersymmetric standard model, it is possible to maintain a flat inflationary direction despite large supergravity corrections, aligning with cosmic microwave background data across a range of Hubble parameters.

Contribution

It introduces a method to preserve flat inflationary directions in supergravity models, even with significant Hubble-induced corrections, applicable to any F-term inflationary scenario.

Findings

A flat direction lifted by an n=6 operator matches CMB data.

The approach works for Hubble parameters between 10^5 and 10^8.5 GeV.

Large supergravity corrections do not necessarily spoil inflation.

Abstract

It is well known that large Hubble-induced supergravity corrections to the inflaton field can ruin the flatness of the potential, thus creating a tension between slow-roll inflation and supergravity. In this paper we show that it is possible to obtain a {\it cosmologically flat} direction, embedded within the minimal supersymmetric standard model, despite very large super-Hubble corrections. As an illustration, we show that a flat direction which is lifted by an $n=6$ operator matches the current cosmic microwave background data for a wide range of the Hubble parameter, $10^{5} {\rm GeV}\lesssim H_{inf}\lesssim 10^{8.5}$ GeV. Our approach can be applied to any $F$-term inflationary model.