Modification of T/E models and their multi-field versions

TL;DR

This paper introduces a modification to T/E supergravity inflation models that simplifies their derivatives at the minimum and extends them to multi-field scenarios, analyzing inflation dynamics and potential observational signatures.

Contribution

It proposes a new superpotential modification for T/E models and develops multi-field versions with detailed inflation dynamics analysis.

Findings

All first derivatives vanish at the minimum after modification.

Multi-field T/E models exhibit specific turning rates and entropic perturbation masses.

The models' inflationary behavior can be tested through observational data.

Abstract

We propose a modification on the super-potential of (arXiv: 1901.09046) which discusses the simplest construction of inflationary $\alpha$ attractor models (also called T/E models) in supergravity without the sinflaton. This can make all the components of the first derivative vanish at the minimum point after the specific choice for the modified part. We also extend T/E models into the multi-field versions, motivated by considering the effect of multi orthogonal nilpotent super-fields, whose sgoldstino, sinflatons and inflatinos are very heavy such that we can take the orthogonal nilpotent constraints to obtain physical limits. Finally, we study the inflation dynamics in the double field cases of both T and E models and show their turning rates and the square mass of the entropic perturbation, which can be used for further observational verification.