Modulus D-term Inflation

TL;DR

This paper introduces a novel single-field D-term inflation model in supergravity, driven by a modulus field with a non-linear U(1) transformation, avoiding the cosmic string problem common in previous models.

Contribution

It presents a new supergravity-based D-term inflation model with a modulus field that preserves the U(1) symmetry in the vacuum, solving the cosmic string issue.

Findings

The model successfully avoids the cosmic string problem.

It maintains a unbroken U(1) symmetry in the vacuum.

Provides a consistent inflationary scenario within supergravity.

Abstract

We propose a new model of single-field D-term inflation in supergravity, where the inflation is driven by a single modulus field which transforms non-linearly under the U(1) gauge symmetry. One of the notable features of our modulus D-term inflation scenario is that the global U(1) remains unbroken in the vacuum and hence our model is not plagued by the cosmic string problem which can exclude most of the conventional D-term inflation models proposed so far due to the CMB observations.