paper

BPS Spectra and Non--Perturbative Couplings in N=2,4 Supersymmetric String Theories

arXiv:hep-th/9512129 · doi:10.1016/0550-3213(96)00069-7

Abstract

We study the BPS spectrum in heterotic string compactifications, with some emphasis on intermediate BPS states. These intermediate states, which can become short in compactifications, are crucial for establishing an exchange symmetry in compactifications. We discuss the implications of a possible exchange symmetry for the BPS spectrum. Then we present the exact result for the 1-loop corrections to gravitational couplings in one of the heterotic models recently discussed by Harvey and Moore. We conjecture this model to have an exchange symmetry. This exchange symmetry can then be used to evaluate non-perturbative corrections to gravitational couplings in some of the non-perturbative regions (chambers) in this particular model and also in other heterotic models.

44 pages, LaTeX. Minor changes, version that will appear in Nucl. Phys. B

References in corpus (8)

Cited by in corpus (37)