Asymmetric Orbifolds and Grand Unification

TL;DR

This paper extends free fermionic string construction rules to include asymmetric orbifolds with world-sheet bosons, enabling the explicit construction of grand unified models with three chiral families in heterotic string theory.

Contribution

It introduces generalized rules for asymmetric orbifolds in string theory and constructs explicit three-family GUT models with level-3 current algebras.

Findings

Constructed three classes of 3-family GUT models with specific gauge groups.

Demonstrated how to obtain SO(10) and SU(5) models using Wilson lines and moduli.

Provided explicit models with three chiral families and Higgs representations.

Abstract

We generalize the rules for the free fermionic string construction to include other asymmetric orbifolds with world-sheet bosons. We use these rules to construct various grand unified string models that involve level-3 current algebras. We present the explicit construction of three classes of 3-chiral-family grand unified models in the heterotic string theory. Each model has 5 left-handed, and two right-handed families, and an adjoint Higgs. Two of them are SO(10) and the third is E_6. With Wilson lines and/or varying moduli, we show how other 3-family grand unified models, such as SO(10) and SU(5), may be constructed from them.