Hierarchies from D-brane instantons in globally defined Calabi-Yau Orientifolds

TL;DR

This paper constructs globally consistent Type I string models on elliptically fibered Calabi-Yau manifolds, demonstrating how D-brane instantons can generate non-perturbative effects like Majorana masses and supersymmetry breaking.

Contribution

It presents the first semi-realistic global Type I string vacua where D-brane instantons produce phenomenologically relevant non-perturbative effects.

Findings

D1-instantons generate Majorana masses at intermediate scales.

D1-instantons induce a Polonyi superpotential for SUSY breaking.

Models are globally consistent and semi-realistic.

Abstract

We construct the first globally consistent semi-realistic Type I string vacua on an elliptically fibered manifold where the zero modes of the Euclidean D1-instanton sector allow for the generation of non-perturbative Majorana masses of an intermediate scale. In another class of global models, a D1-brane instanton can generate a Polonyi-type superpotential breaking supersymmetry at an exponentially suppressed scale.