Toroidal Orientifolds in IIA with General NS-NS Fluxes

TL;DR

This paper explores advanced flux configurations in Type IIA toroidal orientifolds, including metric and non-geometric fluxes, to enhance moduli stabilization and model building, using effective field theory and geometric approaches.

Contribution

It introduces two methods for analyzing flux compactifications with NS-NS fluxes, highlighting the role of D-terms and flux quantization in these models.

Findings

Presence of D-terms in the effective potential.

Subtlety in quantizing NS-NS fluxes.

Application to T^6/Z_4 orientifold example.

Abstract

Type IIA toroidal orientifolds offer a promising toolkit for model builders, especially when one includes not only the usual fluxes from NS-NS and R-R field strengths, but also fluxes that are T-dual to the NS-NS three-form flux. These new ingredients are known as metric fluxes and non-geometric fluxes, and can help stabilize moduli or can lead to other new features. In this paper we study two approaches to these constructions, by effective field theory or by toroidal fibers twisted over a toroidal base. Each approach leads us to important observations, in particular the presence of D-terms in the four-dimensional effective potential in some cases, and a more subtle treatment of the quantization of the general NS-NS fluxes. Though our methods are general, we illustrate each approach on the example of an orientifold of T^6/Z_4.