Brane Supersymmetry Breaking

TL;DR

This paper presents a method to construct string models where supersymmetry is broken on certain branes while remaining intact in the bulk, with implications for low-scale string theories and hierarchy stability.

Contribution

It introduces a new class of chiral, tachyon-free orientifold models with localized supersymmetry breaking that is suppressed in the bulk, relevant for orbifold models with discrete torsion.

Findings

Supersymmetry breaking is localized on branes and suppressed in the bulk.

Models are tachyon-free and maintain chirality.

Hierarchy stability is preserved against gravitational corrections.

Abstract

We show how to construct chiral tachyon-free perturbative orientifold models, where supersymmetry is broken at the string scale on a collection of branes while, to lowest order, the bulk and the other branes are supersymmetric. In higher orders, supersymmetry breaking is mediated to the remaining sectors, but is suppressed by the size of the transverse space or by the distance from the brane where supersymmetry breaking primarily occurred. This setting is of interest for orbifold models with discrete torsion, and is of direct relevance for low-scale string models. It can guarantee the stability of the gauge hierarchy against gravitational radiative corrections, allowing an almost exact supergravity a millimeter away from a non-supersymmetric world.