On the 3-form formulation of axion potentials from D-brane instantons

TL;DR

This paper develops a 3-form field framework to describe axion potentials arising from D-brane instantons, extending previous models to include non-gauge instanton effects via generalized geometry.

Contribution

It introduces a novel 3-form formulation for axion potentials from D-brane instantons, incorporating backreaction effects in generalized geometry.

Findings

3-form field description captures D-brane instanton effects

The 3-form arises in KK compactification, not in the original geometry

Provides a unified framework for non-perturbative axion potentials

Abstract

The study of axion models and quantum corrections to their potential has experienced great progress by phrasing the axion potential in terms of a 3-form field eating up the 2-form field dual to the axion. Such reformulation of the axion potential has been described for axion monodromy models, and for axion potentials from non-perturbative gauge dynamics. In this paper we propose a 3-form description of the axion potentials from non-gauge D-brane instantons. Interestingly, the required 3-form field does not arise in the underlying geometry, but rather shows up in the KK compactification in the generalized geometry obtained when the backreaction of the D-brane instanton is taken into account.