Related papers: Grand Unification with and without Supersymmetry
We describe a new technique which enables one to construct an SO(10)-symmetric fermion mass matrix model at the supersymmetric grand unification scale directly from the fermion mass and mixing data at the low energy scale. Applications to…
Recently SO(10) models with type-II see-saw dominance have been proposed as a promising framework for obtaining Grand Unification theories with approximate Tri-bimaximal (TB) mixing in the neutrino sector. We make a general study of SO(10)…
After a brief review of the flavour problem we present a new predictive framework based on SUSY $SO(10)$ theory, where the first family plays a role of the mass unification point. The inter-family hierarchy is first generated in a sector of…
We discuss the implications of large neutrino mixings for grand unified theories based on the seesaw mechanism. In SU(5) GUTs large mixings can be accomodated by means of $U(1)_F$ flavour symmetries. In these models the heavy Majorana…
We consider supersymmetric SO(10) grand unification where the unified gauge group can break to the Standard Model gauge group through different chains. The breaking of SO(10) necessarily involves the reduction of the rank, and consequent…
The value of the neutrino mass reported by the SuperK collaboration fits beautifully into the framework of gauge theory unification. Here I justify this claim, and review the other main reasons to believe in that framework. Supersymmetry…
The problem of fermion masses and mixings is discussed in the context of supersymmetric grand unification theories. Some predictive frameworks based on the $SU(5)$, $SO(10)$ and $SU(6)$ models are reviewed. [Based on lectures delivered at…
Evidence in favor of supersymmetric grand unification including that based on the observed family multiplet-structure, gauge coupling unification, neutrino oscillations, baryogenesis, and certain intriguing features of quark-lepton masses…
The recent evidence for neutrino oscillations stimulate us to discuss again the problem of fermion masses and mixings in gauge theories. In the standard model, several forms for quark mass matrices are equivalent. They become ansatze within…
A Model based on SO(10) grand unified theory (GUT) and supersymmetry is presented to describe observed phenomena for neutrinos. The large mixing angles among different generations, together with the small masses, are attributed to the Higgs…
The possibility of grand unification of the standard model (SM) with fermion spectrum extended to include mirror fermions is examined. SM gauge couplings do not automatically unify. SO(10) grand unification is studied with one intermediate…
Grand unified theories open the possibility to transfer the neutrino mixing matrix U_PMNS to the quark sector. This is accomplished in a controlled way in a supersymmetric grand-unified model proposed by Chang, Masiero and Murayama (CMM…
We discuss whether quark, charged lepton and neutrino masses and mixing angles may be related by an extended flavour and family symmetry group. We show that current measurements of all fermion masses and mixing angles are consistent with a…
An alternative supersymmetric SO(10) grand unification model with lopsided fermion mass matrices is introduced. It generates a large solar-neutrino-mixing angle through the neutrinos' Dirac mass matrix constrained by the SO(10) group…
We provide a unified description of fermion masses and mixing angles in the framework of a supersymmetric grand unified SO(10) model with anarchic Yukawa couplings of order unity. The space-time is five dimensional and the extra flat…
O(10) grand unification models which do not necessarily have an extra global symmetry are discussed, taking the model with one 10-plet in the Yukawa sector as an example. A strong correlation between mass ratios and CP is found. The mass…
We briefly review the issues of proton decay and fermion masses and mixings in minimal supersymmetric grand unified theories. We argue that minimal SU(5), although tightly constrained by proton decay data, is still not ruled out. However,…
The problem of neutrino masses and mixing angles is analysed in a class of supersymmetric grand unified models, with SO(10) gauge symmetry and global U(2) flavour symmetry. Adopting the seesaw mechanism for the generation of the neutrino…
We suggest a simple composite model that induces the large flavor mixing of neutrino in the supersymmetric theory. This model has only one hyper-color in addition to the standard gauge group, which makes composite states of preons. In this…
A non-minimal, semi-realistic version of supersymmetric SU(5) grand unified theory is discussed. The solution of the doublet-triplet splitting problem leads to a better agreement between the predicted and observed values of the low-energy…