# Deforming the Starobinsky model in ghost-free higher derivative supergravities

## TL;DR

This paper explores higher derivative supergravity models dual to ghost-free N=1 supergravities, deforming the Kähler function and superpotential to achieve Starobinsky-like inflationary behavior.

## Contribution

It introduces a novel class of no-scale supergravity models with nonlinear dependences on chiral fields, extending the Starobinsky model within a ghost-free higher derivative framework.

## Key findings

- Models are dual to ghost-free supergravities in Einstein frame.
- Deformations lead to multifield scalar potentials with Starobinsky-like features.
- Minimal models involve four chiral multiplets with specific Kähler geometry.

## Abstract

We consider higher derivative supergravities that are dual to ghost-free $N=1$ supergravity theories in the Einstein frame. The duality is implemented by deforming the K\"ahler function, and/or the superpotential, to include nonlinear dependences on chiral fields that in other approaches play the role of the Lagrange multipliers employed to establish this duality. These models are of the no-scale type, and in the minimal case, require the presence of four chiral multiplets, with a K\"ahler potential having the structure of the $ SU(4,1)/SU(4) \times U(1) $ coset manifold. In the standard $N=1$ supergravity formulation, these models are described by a multifield scalar potential, featuring Starobinsky-like behavior in particular directions.