UV Corrections in Sgoldstino-less Inflation

TL;DR

This paper investigates supergravity models of inflation with nilpotent multiplets, focusing on how heavy sgoldstino fields can be integrated out, and identifies conditions under which sgoldstino-less inflation remains viable despite potential corrections.

Contribution

It provides explicit supergravity models with finite sgoldstino mass from Yukawa or gauge interactions, analyzing the effects of heavy fields on inflationary potential corrections.

Findings

Sgoldstino decoupling is nontrivial due to competing correction scales.

A parameter window exists where sgoldstino-less inflation is consistent.

Corrections tend to flatten the inflaton potential.

Abstract

We study the embedding of inflation with nilpotent multiplets in supergravity, in particular the decoupling of the sgoldstino scalar field. Instead of being imposed by hand, the nilpotency constraint on the goldstino multiplet arises in the low energy-effective theory by integrating out heavy degrees of freedom. We present explicit supergravity models in which a large but finite sgoldstino mass arises from Yukawa or gauge interactions. In both cases the inflaton potential receives two types of corrections. One is from the backreaction of the sgoldstino, the other from the heavy fields generating its mass. We show that these scale oppositely with the Volkov-Akulov cut-off scale, which makes a consistent decoupling of the sgoldstino nontrivial. Still, we identify a parameter window in which sgoldstino-less inflation can take place, up to corrections which flatten the inflaton potential.