Heterotic Coset Models and (0,2) String Vacua

TL;DR

This paper develops a Lagrangian framework for (0,2) heterotic coset models, exploring their algebraic structure, modular invariants, and applications in constructing four-dimensional string theories with specific gauge groups.

Contribution

It introduces a gauge-invariant Lagrangian formulation of (0,2) heterotic coset models and constructs modular invariant partition functions, advancing the understanding of (0,2) string vacua.

Findings

Detailed study of (0,2) heterotic coset models

Construction of modular invariant partition functions

Examples of four-dimensional string theories with specific gauge groups

Abstract

A Lagrangian definition of a large family of (0,2) supersymmetric conformal field theories may be made by an appropriate gauge invariant combination of a gauged Wess-Zumino-Witten model, right-moving supersymmetry fermions, and left-moving current algebra fermions. Throughout this paper, use is made of the interplay between field theoretic and algebraic techniques (together with supersymmetry) which is facilitated by such a definition. These heterotic coset models are thus studied in some detail, with particular attention paid to the (0,2) analogue of the N=2 minimal models, which coincide with the `monopole' theory of Giddings, Polchinski and Strominger. A family of modular invariant partition functions for these (0,2) minimal models is presented. Some examples of N=1 supersymmetric four dimensional string theories with gauge groups E_6 X G and SO(10) X G are presented, using these minimal models as building blocks. The factor G represents various enhanced symmetry groups made up of products of SU(2) and U(1).