Related papers: Grand Unified Theories
We recapitulate the primary sources of theoretical uncertainties in proton lifetime estimates in renormalizable, four-dimensional and non-supersymmetric grand unifications that represent the most conservative framework in which this…
The extended supersymmetric SO(10) model with missing partner mechanism is studied. An intermediate vacuum expectation value is incorporated which corresponds to the see-saw scale. Gauge coupling unification is not broken explicitly. Proton…
We embed a theory with Zprime gauge boson (related to extra U(1) gauge group) into a supersymmetric GUT theory based on SO(10). Two possible sequences of SO(10) breaking via VEVs of appropriate Higgs fields are considered. Gauge coupling…
We construct a realistic SU(7) model which provides answers to many questions presently facing the prototype SU(5) SUSY GUT. Among them are a solution to the doublet-triplet splitting problem, string scale unification, proton decay, the…
We propose an SU(5)$\times $U(1)$_\text{X}\times$U(1)$_\text{PQ}$ model without SUSY because the SUSY particles have not been observed yet. The $\mathrm{U(1)_{X}}$ gauge symmetry is the generalization of the $\mathrm{U(1)_{B-L}}$ gauge…
Grand Unified Theories (GUTs) are attractive candidates for more fundamental elementary particle theories. They can not only unify the Standard Model (SM) interactions but also different types of SM fermions, in particular quarks and…
I discuss several issues concerning the use of string models as unified theories of all interactions. After a short review of gauge coupling unification in the string context, I discuss possible motivations for the construction of $SU(5)$…
We review the status of a class of gauge unified models based on SO(10) group and discuss the main phenomenological implications of these models in particular for neutrino masses.
In simple SO(10) SUSY GUTs the top, bottom and tau Yukawa couplings unify at the GUT scale. A naive renormalization group analysis, neglecting weak scale threshold corrections, leads to moderate agreement with the low energy data. However…
We study the breaking of supersymmetry and its transmission to the light states in the context of the minimal SU(5) grand unified theory, with no additional singlets. This simple theory can be taken as a prototype for a program of breaking…
We present a detailed study of the quark and lepton mass spectra in a SO(10) framework with one 10_H and one \bar{126}_H Higgs representations in the Yukawa sector. We consider in full generality the interplay between type-I and type-II…
We study models of supersymmetric grand unification based on the SO(10) gauge group. We investigate scenarios of non-universal gaugino masses including models containing a mixture of two representations of hidden sector chiral superfields.…
Grand gauge-Higgs unification of five dimensional SU(6) gauge theory on an orbifold $S^1/Z_2$ with localized gauge kinetic terms is discussed. The Standard model (SM) fermions on the boundaries and some massive bulk fermions coupling to the…
We consider SUSY SO(10) models in which SUSY breaking occurs via an F-term which does not transform as an SO(10) singlet. This results in non-universal GUT-scale gaugino masses leading to a different pattern of sparticle masses from what is…
In the minimal SUSY SU(5) GUT with $O(1)$ TeV SUSY particles and $O(1)$ or below self-coupling for the GUT-breaking Higgs field, the width of the dimension-6 proton decay is suppressed below the reach of Hyper-Kamiokande. In this paper, we…
Evaluation of nucleon decay modes and branching ratios in a non-minimal supersymmetric SO(10) grand unified theory is presented. The non-minimal GUT considered is the supersymmetrised version of the `realistic' SO(10) model originally…
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)…
It is shown that embedding of flipped SU(5) in a five-dimensional SO(10) enables exact unification of the gauge coupling constants. The demand for the unification uniquely determines both the compactification scale and the cutoff scale.…
In this article we review proton decay in the supersymmetric grand unified models.
LHC constraints on the recently proposed SUSY SO(10) GUT model with top-bottom-tau Yukawa unification are investigated. In this model, various phenomenological constraints are in concord with the Yukawa unification thanks to the negative…