paper

A WAY TO BREAK SUPERSYMMETRY

arXiv:hep-th/9503030

Abstract

I study the spontaneous breakdown of supersymmetry when higher-dimensional Yang-Mills or the type-I string theory are compactified on magnetized tori. Because of the universal gyromagnetic ratio , the splittings of all multiplets are given by the product of charge times internal helicity operators. As a result such compactifications have two remarkable and robust features: {\it (a)} they can reconcile {\it chirality} with {\it extended} low-energy supersymmetry in the limit of large tori, and {\it (b)} they can trigger gauge-symmetry breaking, via Nielsen-Olesen instabilities, at a scale tied classically to . I exhibit a compactification of the superstring, in which magnetic fields break spontaneously supersymmetry, produce the standard-model gauge group with three chiral families of quarks and leptons, and trigger electroweak symmetry breaking. I discuss supertrace relations and the ensuing ultraviolet softness. As with other known mechanisms of supersymmetry breaking, the one proposed here faces two open problems: the threat to perturbative calculability in the decompactification limit, and the problem of gravitational stability and in particular of the cosmological constant. I explain, however, why a good classical description of the vacuum may require small tadpoles for the dilaton, moduli and metric.

20 pages, Latex file

Cited by in corpus (175)