Single-Superfield Helical-Phase Inflation

TL;DR

This paper introduces a simplified class of helical-phase inflation models in supergravity that do not require a stabilizer superfield, including quadratic, natural, and Starobinsky-type models.

Contribution

It proposes a more economical helical-phase inflation model without stabilizer superfields, expanding the class of viable supergravity inflation scenarios.

Findings

Models successfully realize inflation without stabilizer superfields.

The approach includes quadratic, natural, and Starobinsky-type inflation models.

The models are consistent with observational constraints.

Abstract

Large-field inflation in supergravity requires the approximate global symmetry needed to protect flatness of the scalar potential. In helical-phase inflation, the U(1) symmetry of the Kahler potential is assumed, the phase part of the complex scalar of a chiral superfield plays the role of inflaton, and the radial part is strongly stabilized. The original model of helical phase inflation, proposed by Li, Li and Nanopoulos (LLN), employs an extra (stabilizer) superfield. We propose a more economical new class of the helical phase inflationary models without a stabilizer superfield. As the specific examples, the quadratic, the natural, and the Starobinsky-type inflationary models are studied in our approach.