# $F$-term Multi-Field Inflation in Supergravity without Stabiliser Superfields

## TL;DR

This paper presents a new supergravity inflation model that avoids the stabiliser superfield, broadening the scope of $F$-term inflation by extending an alternative mechanism to multi-field scenarios, with concrete examples and stability conditions.

## Contribution

It introduces a general framework for multi-field $F$-term inflation in supergravity without stabiliser superfields, expanding the theoretical possibilities beyond previous models.

## Key findings

- Successfully extended the alternative mechanism to multi-field models.
- Provided concrete examples demonstrating the approach.
- Clarified conditions to prevent tachyonic instabilities.

## Abstract

Realising $F$-term slow-roll inflation in supergravity is non-trivial due to the well-known $\eta$-problem. The common strategy to solve the problem is to impose a shift symmetry on the K\"ahler potential, but this often leads to a negative potential in the large-field regime. To avoid negative potentials, an additional superfield called the stabiliser is usually added with a desired interaction. An alternative mechanism in supergravity, avoiding the use of a stabiliser superfield, was earlier proposed by two of us in the setup with a single chiral superfield having inflaton and goldstino amongst its field components. In this work, we extend that alternative mechanism to multi-superfield models of inflation, thereby providing a generic framework for embedding a wide class of single- and multi-field inflation models into supergravity. We illustrate our approach by several concrete examples of multi-field inflation and clarify the conditions required to avoid tachyonic instabilities during multi-field evolution. Our proposal significantly broadens the theoretical landscape of $F$-term inflation models in supergravity.