Spectra of Heterotic Strings on Orbifolds

TL;DR

This paper analyzes the spectrum of heterotic strings compactified on orbifolds, emphasizing algebraic structures like affine Lie algebras, twisted sectors, and charge relations to understand their properties.

Contribution

It introduces a detailed algebraic framework for heterotic string spectra on orbifolds, including twisted sectors and charge relations, advancing understanding of their structure.

Findings

Characterization of the twisted spectrum and Abelian charges

Use of affine Lie algebra to describe current algebra and representations

Development of a rule relating conformal weight to mass

Abstract

We obtain the spectrum of heterotic strings compactified on orbifolds, focusing on its algebraic structure. Affine Lie algebra provides its current algebra and representations. In particular the twisted spectrum and the Abelian charge are understood. The twisted version of algebra is used in the homomorphism from the orbifold action to the group action. The relation between the conformal weight and the mass gives a handy rule.