相关论文: Flipping SU(5) Towards Five Dimensional Unificatio…

It is shown that embedding a four-dimensional flipped SU(5) model in a five-dimensional SO(10) model, preserves the best features of both flipped SU(5) and SO(10). The missing partner mechanism, which naturally achieves both doublet-triplet…

Gauge unification in a five dimensional supersymmetric SO(10) model compactified on an orbifold $S^1/(Z_2 \times Z_2^{\prime})$ is studied. One orbifolding reduces N=2 supersymmetry to N=1, and the other breaks SO(10) to the Pati-Salam…

A complete 5-dimensional SU(5) unified theory is constructed which, on compactification on the orbifold with two different Z_2's (Z_2 and Z_2'), yields the minimal supersymmetric standard model. The orbifold accomplishes SU(5) gauge…

We consider a 5-dimensional SU(5) model wherein the symmetry is broken to the 4-dimensional Standard Model by compactification of the 5th dimension on an S^1/(Z_2 \times Z^\prime_2) orbifold. We identify the members of all SU(5)…

Maximally supersymmetric SO(10) and SU(6) unified theories are constructed on the orbifold T^2/(Z_2 x Z'_2), with one length scale R_5 taken much larger than the other, R_6. The effective theory below 1/R_6 is found to be the highly…

It is pointed out that a class of flipped SU(5) models based on F-theory naturally explains the gauge coupling unification. It is because the group SU(5) x U(1)_X is embedded in SO(10) and E_8. To prohibit the dimension 4 and 5 proton decay…

We study in detail the d=6 operators for proton decay in the two possible matter unification scenarios based on SU(5) gauge symmetry. We investigate the way to distinguish between these two scenarios. The dependence of the branching ratios…

SU(5) $\otimes$ SU(5) provides a minimal grand unification scheme for fermions and gauge forces if there are vector-like quarks and leptons in nature. We explore the gauge coupling unification in a non-supersymmetric model of this type, and…

The idea of grand unification in a minimal supersymmetric SU(5)xSU(5) framework is revisited. It is shown that the unification of gauge couplings into a unique coupling constant can be achieved at a high-energy scale compatible with proton…

We propose a realistic flipped SU(5) model derived from a five-dimensional orbifold SO(10) model. The Standard Model (SM) fermion masses and mixings are explained by combining the traditional Froggatt-Nielsen mechanism with the…

We study supersymmetric (SUSY) flipped $SU(5)\times U(1)$ unification, focussing on its predictions for proton decay, fermion masses and gravitational waves. We performed a two-loop renormalisation group analysis and showed that the SUSY…

We consider the scenario where all the couplings in the theory are strong at the cut-off scale, in the context of higher dimensional grand unified field theories where the unified gauge symmetry is broken by an orbifold compactification. In…

Higher dimensional grand unified theories, with gauge symmetry breaking by orbifold compactification, possess SU(5) breaking at fixed points, and do not automatically lead to tree-level gauge coupling unification. A new framework is…

Quantum gravity or string compactification can lead to effective dimension-5 operators in Grand Unified Theories which modify the gauge kinetic terms. We exhaustively discuss the group-theoretic nature of such operators for the popular…

Based on the Z_{12-I} orbifold compactification of the heterotic string theory, we construct a flipped-SU(5) model with three families of the standard model matter and ingredients for dynamical supersymmetry breaking. The doublet-triplet…

A fully realistic unified theory is constructed, with SU(5) gauge symmetry and supersymmetry both broken by boundary conditions in a fifth dimension. Despite the local explicit breaking of SU(5) at a boundary of the dimension, the large…

We construct SU(5) SUSY GUT in 5D compactified on S^1/Z_2 orbifold where the matter fields are living in the five dimensional bulk. SU(5) symmetry is broken down to the Standard Model gauge group by the orbifold projection which…

We systematically construct flipped SU(5) X U(1)_X models without and with bulk vector-like particles from F-theory. To realize the decoupling scenario, we introduce sets of vector-like particles in complete SU(5) X U(1) multiplets at the…

We investigate the unification constraints in the minimal sypersymmetric grand unified theories based on SU(5) gauge symmetry. The most general constraints on the spectrum of minimal supersymmetric SU(5) and flipped SU(5) are shown. The…

We construct a minimal supersymmetric SO(10) grand unified model in 5 dimensions. The extra dimension is compactified on an S^1/(Z_2 x Z_2^\prime) orbifold which has two in-equivalent fixed points. These are flat 4-dimensional Minkowski…