A Solution to the Doublet-Triplet Splitting Problem in the Type IIB Supergravity
arXiv:hep-ph/0208107
Abstract
The doublet--triplet mass splitting problem is one of the most serious problems in supersymmetric grand unified theories (GUTs). A class of models based on a product gauge group, such as the SU(5)_{GUT} times U(3)_H or the SU(5)_{GUT} times U(2)_H, realize naturally the desired mass splitting that is protected by an unbroken R symmetry. It has been pointed out that various features in the models suggest that these product-group unification models are embedded in a supersymmetric brane world. We show an explicit construction of those models in the supersymmetric brane world based on the Type IIB supergravity in ten dimensions. We consider T^6/(Z_{12} times Z_2) orientifold for the compactified six extra dimensions. We find that all of the particles needed for the GUT-symmetry-breaking sector are obtained from the D-brane fluctuations. The three families of quarks and leptons are introduced at an orbifold singularity, although their origin remains unexplained. This paper includes extensive discussion on anomaly cancellation in a given orbifold geometry. Relation to the Type IIB string theory, realization of R symmetry as a rotation of extra-dimensional space, and effective superpotential at low energies are also discussed.
61 pages
References in corpus (20)
- Large N Field Theories, String Theory and Gravity
- D-branes, Quivers, and ALE Instantons
- Consistency Conditions for Orientifolds and D-Manifolds
- Gauge Unification in Higher Dimensions
- Not Even Decoupling Can Save Minimal Supersymmetric SU(5)
- Supersymmetric String Solitons
- Effect of an RRRR dimension 5 operator on the proton decay in the minimal SU(5) SUGRA GUT model
- Note on Discrete Gauge Anomalies
- New Phases of String Theory and 6d RG Fixed Points via Branes at Orbifold Singularities
- M-theory from its superalgebra
- A Complete Theory of Grand Unification in Five Dimensions
- Branes within Branes
- Naturally Light Higgs Doublets in the Supersymmetric Grand Unified Theories with Dynamical Symmetry Breaking
- Intersecting Branes Flip SU(5)
- Brane Boxes, Anomalies, Bending and Tadpoles
- A Note on Superconformal N=2 theories and Orientifolds
- Natural Unification with a Supersymmetric SO(10) SO(6) Gauge Theory
- Lectures on Strings and Dualities
- Semi-Simple Unification on T^6/Z_12 Orientifold in the Type IIB Supergravity
- R-Invariant Unification with Dynamical Higgs Multiplets