Duality Orbits, Dyon Spectrum and Gauge Theory Limit of Heterotic String Theory on T^6

TL;DR

This paper characterizes the T-duality invariants for dyons in heterotic string theory on T^6, extending degeneracy formulas and deriving the quarter BPS dyon spectrum in N=4 gauge theories, aligning with field theory results.

Contribution

It identifies the complete set of T-duality invariants and extends the dyon degeneracy formula to a broader class of dyons in heterotic string theory.

Findings

Complete set of T-duality invariants derived

Extended degeneracy formula for dyons established

Spectrum of quarter BPS dyons matches field theory predictions

Abstract

For heterotic string theory compactified on T^6, we derive the complete set of T-duality invariants which characterize a pair of charge vectors (Q,P) labelling the electric and magnetic charges of the dyon. Using this we can identify the complete set of dyons to which the previously derived degeneracy formula can be extended. By going near special points in the moduli space of the theory we derive the spectrum of quarter BPS dyons in N=4 supersymmetric gauge theory with simply laced gauge groups. The results are in agreement with those derived from field theory analysis.