GUTs in Type IIB Orientifold Compactifications

TL;DR

This paper constructs and analyzes globally consistent SU(5) GUT models within Type IIB Calabi-Yau orientifolds, addressing complex geometric constraints and presenting explicit models with realistic phenomenological features.

Contribution

It introduces new classes of Calabi-Yau manifolds suitable for GUT model building and provides explicit globally consistent models with realistic particle physics features.

Findings

Five consistent string GUT models constructed

A 3-generation SU(5) model with no exotics

Identification of swiss-cheese Calabi-Yau manifolds for moduli stabilisation

Abstract

We systematically analyse globally consistent SU(5) GUT models on intersecting D7-branes in genuine Calabi-Yau orientifolds with O3- and O7-planes. Beyond the well-known tadpole and K-theory cancellation conditions there exist a number of additional subtle but quite restrictive constraints. For the realisation of SU(5) GUTs with gauge symmetry breaking via U(1)_Y flux we present two classes of suitable Calabi-Yau manifolds defined via del Pezzo transitions of the elliptically fibred hypersurface P_{1,1,1,6,9}[18] and of the Quintic P_{1,1,1,1,1}[5], respectively. To define an orientifold projection we classify all involutions on del Pezzo surfaces. We work out the model building prospects of these geometries and present five globally consistent string GUT models in detail, including a 3-generation SU(5) model with no exotics whatsoever. We also realise other phenomenological features such as the 10 10 5 Yukawa coupling and comment on the possibility of moduli stabilisation, where we find an entire new set of so-called swiss-cheese type Calabi-Yau manifolds. It is expected that both the general constrained structure and the concrete models lift to F-theory vacua on compact Calabi-Yau fourfolds.