Starobinsky inflation from new-minimal supergravity

TL;DR

This paper embeds the Starobinsky inflation model within new-minimal supergravity, deriving a single-field inflation scenario with a massive vector, and discusses higher order corrections and initial conditions.

Contribution

It provides a superspace formulation of the Starobinsky model in new-minimal supergravity, highlighting the emergence of a massive vector and addressing higher order effects.

Findings

Successful embedding of Starobinsky inflation in supergravity

Identification of a propagating massive vector field

Discussion on higher order corrections and initial conditions

Abstract

In the new-minimal supergravity formulation we present the embedding of the $R+R^2$ Starobinsky model of inflation. Starting from the superspace action we perform the projection to component fields and identify the Starobinsky model in the bosonic sector. Since there exist no other scalar fields, this is by construction a single field model. This higher curvature supergravity also gives rise to a propagating massive vector. Finally we comment on the issues of higher order corrections and initial conditions.