Non-SUSY Heterotic String Vacua of Gepner Models with Vanishing Cosmological Constant

TL;DR

This paper constructs and classifies non-supersymmetric heterotic string vacua with zero one-loop cosmological constant using asymmetric orbifolds of Gepner models, expanding understanding of stable string solutions.

Contribution

It introduces a systematic method to build and classify non-SUSY heterotic vacua with vanishing cosmological constant via asymmetric orbifolds of Gepner models.

Findings

Classification of orbifold models leading to desired vacua

Construction of vacua similar to type II models with discrete torsions

Simpler models as asymmetric orbifolds of cyclic groups

Abstract

We study a natural generalization of that given in [arXiv:2005.13198 [hep-th]] to heterotic string. Namely, starting from the generic Gepner models for Calabi-Yau 3-folds, we construct the non-SUSY heterotic string vacua with the vanishing cosmological constant at the one loop. We especially focus on the asymmetric orbifolding based on some discrete subgroup of the chiral $U(1)$-action which acts on both of the Gepner model and the $SO(32)$ or $E_8\times E_8$-sector. We present a classification of the relevant orbifold models leading to the string vacua with the properties mentioned above. In some cases, the desired vacua can be constructed in the manner quite similar to those given in [arXiv:2005.13198 [hep-th]] for the type II string, in which the orbifold groups contain two generators with the discrete torsions. On the other hand, we also have simpler models that are just realized as the asymmetric orbifolds of cyclic groups with only one generator.