Non-geometric flux vacua, S-duality and algebraic geometry

TL;DR

This paper investigates S-duality invariant flux vacua in type IIB string theory compactified on a specific orientifold, developing algebraic geometry methods to systematically solve flux constraints and identify supersymmetric Minkowski solutions.

Contribution

It introduces a systematic algebraic geometry-based method to solve flux constraints in S-duality invariant supergravity models from non-geometric string compactifications.

Findings

Fluxes can be implemented as linear deformations of the gauge algebra.

Systematic solutions for supersymmetric Minkowski vacua are obtained.

The approach clarifies the algebraic structure underlying flux constraints.

Abstract

The four dimensional gauged supergravities descending from non-geometric string compactifications involve a wide class of flux objects which are needed to make the theory invariant under duality transformations at the effective level. Additionally, complex algebraic conditions involving these fluxes arise from Bianchi identities and tadpole cancellations in the effective theory. In this work we study a simple T and S-duality invariant gauged supergravity, that of a type IIB string compactified on a $T^6/(Z_2 x Z_2)$ orientifold with O3/O7-planes. We build upon the results of recent works and develop a systematic method for solving all the flux constraints based on the algebra structure underlying the fluxes. Starting with the T-duality invariant supergravity, we find that the fluxes needed to restore S-duality can be simply implemented as linear deformations of the gauge subalgebra by an element of its second cohomology class. Algebraic geometry techniques are extensively used to solve these constraints and supersymmetric vacua, centering our attention on Minkowski solutions, become systematically computable and are also provided to clarify the methods.