Grand Unification with Three Generations in Free Fermionic String Models

Abstract

We examine the problem of constructing three generation free fermionic string models with grand unified gauge groups. We attempt the construction of $G\times G$ models, where $G$ is a grand unified group realized at level 1. This structure allows those Higgs representations to appear which are necessary to break the symmetry down to the standard model gauge group. For $G=SO(10)$, we find only models with an even number of generations. However, for $G=SU(5)$ we find a number of 3 generation models.

22 pages, latex. References added to original version

References in corpus (10)

• String Consistency for Unified Model Building
• Z_2\times Z_2$ orbifold compactification as the origin of realistic free fermionic models
• String GUTs
• Gauge Coupling Unification in Realistic Free-Fermionic String Models
• Gauge Coupling Unification: Strings versus SUSY-GUTs
• Custodial nonabelian gauge symmetries in realistic superstring derived models
• Some Three Generation (0,2) Calabi-Yau Models
• Strings versus supersymmetric GUTs: can they be reconciled?
• Fermion masses and mixings in a flavour symmetric GUT
• Number of Generations in Free Fermionic String Models,

Cited by in corpus (17)

• Stable Superstring Relics
• Realizing Higher-Level Gauge Symmetries in String Theory: New Embeddings for String GUTs
• Three-Family $SO(10)$ Grand Unification in String Theory
• Calculating Fermion masses in Superstring Derived Standard-like Models
• Asymmetric Orbifolds and Higher Level Models
• The Essential Role of String-Derived Symmetries in Ensuring Proton-Stability and Light Neutrino Masses
• New Constraints on SO(10) Model-Building from String Theory
• A Family--Universal Anomalous U(1) in String Models as the Origin of Supersymmetry Breaking and Squark Degeneracy
• A Classification of 3-Family Grand Unification in String Theory I. The SO(10) and E_6 Models
• Asymmetric Orbifolds and Grand Unification
• Local discrete symmetries from superstring derived models
• Three-Family SU(5) Grand Unification in String Theory
• Light adjoint scalars and unification at the string scale
• String scale unification in an SU(6)xSU(2) GUT
• Free Fermionic Constructions of Heterotic Strings
• Options for Orbifold-GUT Model Building from Five-Dimensional Supergravity
• Hybrid MSW + VO Solution of the Solar Neutrino Problem in String-Motivated Unified Theories