The Imaginary Starobinsky Model and Higher Curvature Corrections

TL;DR

This paper explores the imaginary Starobinsky inflation model within supergravity, analyzing how higher curvature corrections influence inflationary predictions, leading to models with quadratic or fractional power monomial potentials.

Contribution

It introduces the effects of higher-order curvature terms on the imaginary Starobinsky model, revealing new inflationary potential forms with fractional powers.

Findings

Higher curvature terms can produce quadratic inflation models.

Depending on parameters, fractional power monomial inflation models emerge.

The model's predictions vary with the inclusion of higher-order corrections.

Abstract

We elaborate on the predictions of the imaginary Starobinsky model of inflation coupled to matter, where the inflaton is identified with the imaginary part of the inflaton multiplet suggested by the Supergravity embedding of a pure R + R^2 gravity. In particular, we study the impact of higher-order curvature terms and show that, depending on the parameter range, one may find either a quadratic model of chaotic inflation or monomial models of chaotic inflation with fractional powers between 1 and 2.