Standard Grand Unification from Superstrings

TL;DR

This paper discusses constructing standard grand unified theories like SO(10) and SU(5) from 4D superstring models, focusing on techniques, constraints, and phenomenological implications.

Contribution

It introduces explicit methods using higher level affine Lie algebras and symmetric orbifolds to build string-based GUTs, clarifying generic versus specific constraints.

Findings

Successful construction of string GUTs with explicit techniques

Identification of key constraints and selection rules

Brief discussion of phenomenological implications

Abstract

Recent developments about the construction of standard $SO(10)$ and $SU(5)$ grand unified theories from 4-dimensional superstrings are presented. Explicit techniques involving higher level affine Lie algebras, for obtaining such stringGUTs from symmetric orbifolds are discussed. Special emphasis is put on the different constraints and selection rules for model building in this string framework, trying to disentangle those which are generic from those depending on the orbifold construction proposed. Some phenomenological implications from such constraints are briefly discussed.