Toroidal Orbifold Models with a Wess-Zumino Term

TL;DR

This paper explores a Lagrangian path integral approach to closed bosonic string theory on toroidal orbifolds, introducing a twisted WZW action as a natural extension of string actions with background fields.

Contribution

It presents a novel formulation using a level one twisted WZW action restricted to Cartan subgroups, extending string theory on orbifolds with background fields.

Findings

WZW action provides a consistent extension of string theory on orbifolds.

The approach links orbifold models with Lie group structures.

New insights into background field effects in string theory.

Abstract

Closed bosonic string theory on toroidal orbifolds is studied in a Lagrangian path integral formulation. It is shown that a level one twisted WZW action whose field value is restricted to Cartan subgroups of simply-laced Lie groups on a Riemann surface is a natural and nontrivial extension of a first quantized action of string theory on orbifolds with an antisymmetric background field.