String-String triality for d=4, Z_2 orbifolds

TL;DR

This paper explores dualities between different string theories with N=4 and N=2 supersymmetry in four dimensions, focusing on Z_2 orbifolds and their perturbative and non-perturbative correspondences.

Contribution

It provides a detailed analysis of the dual relationships between heterotic, type I, and type II string constructions involving Z_2 orbifolds, extending previous classifications.

Findings

Established dualities between heterotic and type I string models

Analyzed perturbative and non-perturbative correspondences in Z_2 orbifolds

Extended classification of symmetric Z_2 x Z_2 orbifolds

Abstract

We investigate the perturbative and non-perturbative correspondence of a class of four dimensional dual string constructions with N=4 and N=2 supersymmetry, obtained as Z_2 or Z_2 x Z_2 orbifolds of the type II, heterotic and type I string. In particular, we discuss the heterotic and type I dual of all the symmetric Z_2 x Z_2 orbifolds of the type II string, classified in hep-th/9901123. .