Topological constraints on stabilized flux vacua

TL;DR

This paper investigates how four-form fluxes and topological M5-instantons influence the stabilization of Kahler moduli in M-theory compactifications, revealing new topological constraints on suitable four-folds.

Contribution

It introduces a novel topological type of M5-instantons that generate superpotentials, expanding understanding of flux-induced moduli stabilization mechanisms.

Findings

M5-instantons of a new topological type generate superpotentials.

Topological constraints differ from flux-free nonperturbative effects.

Certain four-folds are restricted for stabilization by this mechanism.

Abstract

We study the influence of four-form fluxes on the stabilization of the Kahler moduli in M-theory compactified on a Calabi-Yau four-fold. We find that, under certain non-degeneracy condition on the flux, M5-instantons of a new topological type generate a superpotential. The existence of such an instanton restricts possible four-folds for which the stabilization by this mechanism is expected. These topological constraints on the background are different from the previously known constraints, derived from the flux-free analysis of the nonperturbative effects.