Five-Brane Superpotentials, Blow-Up Geometries and SU(3) Structure Manifolds

TL;DR

This paper explores the geometry and superpotentials of five-branes in heterotic and orientifold Calabi-Yau compactifications, introducing blow-up geometries and SU(3) structures to unify brane and bulk dynamics.

Contribution

It introduces a novel blow-up geometry approach to study five-brane superpotentials and derives open-closed Picard-Fuchs equations for these systems.

Findings

Computed the brane superpotential at special points.

Derived open-closed Picard-Fuchs differential equations.

Proposed a non-Kaehler SU(3) structure for heterotic backgrounds.

Abstract

We investigate the dynamics of space-time filling five-branes wrapped on curves in heterotic and orientifold Calabi-Yau compactifications. We first study the leading N=1 scalar potential on the infinite deformation space of the brane-curve around a supersymmetric configuration. The higher order potential is also determined by a brane superpotential which we compute for a subset of light deformations. We argue that these deformations map to new complex structure deformations of a non-Calabi-Yau manifold which is obtained by blowing up the brane-curve into a four-cycle and by replacing the brane by background fluxes. This translates the original brane-bulk system into a unifying geometrical formulation. Using this blow-up geometry we compute the complete set of open-closed Picard-Fuchs differential equations and identify the brane superpotential at special points in the field space for five-branes in toric Calabi-Yau hypersurfaces. This has an interpretation in open mirror symmetry and enables us to list compact disk instanton invariants. As a first step towards promoting the blow-up geometry to a supersymmetric heterotic background we propose a non-Kaehler SU(3) structure and an identification of the three-form flux.