Moduli and Twisted Sector Dependence of Z_N x Z_M Orbifold Couplings

TL;DR

This paper derives explicit four-point correlation functions for twist fields in Z_N x Z_M orbifold compactifications, providing a general conformal field theory framework that respects target space duality.

Contribution

It presents a comprehensive derivation of correlation functions involving twist fields for arbitrary even-dimensional Z_N x Z_M orbifolds, including general modular backgrounds and twisted sectors.

Findings

Correlation functions are target space duality invariant.

Explicit formulas for four-point twist field correlators.

General framework applicable to various orbifold compactifications.

Abstract

We derive the four point correlation function involving four twist fields for arbitrary even dimensional Z_N x Z_M orbifold compactifications. Using techniques from the conformal field theory the three point correlation functions with twist fields are determined. Both the choice of the modular background (compatible with the twists) and of the (higher) twisted sectors involved are fully general. Our results turn out to be target space duality invariant.