Related papers: New and improved quark-lepton symmetric models
To generate the lepton and quark masses in the left-right symmetric models, we can consider a universal seesaw scenario by integrating out heavy fermion singlets which have the Yukawa couplings with the fermion and Higgs doublets. The…
Against the conventional picture that the mass matrix forms in the quark sectors will take somewhat different structures from those in the lepton sectors, on the basis of an idea that all the mass matrices of quarks and leptons have the…
We systematically investigate the parameter space of neutrino and charged lepton mass matrices for textures motivated by an extended quark-lepton complementarity. As the basic hypothesis, we postulate that all mixing angles in U_l and U_nu…
We study the consequences of the $Z_2$-symmetry behind the $\mu$--$\tau$ universality in neutrino mass matrix. We then implement this symmetry in the type-I seesaw mechanism and show how it can accommodate all sorts of lepton mass…
Numerous recent evidences for neutrino masses have established the leptogenesis mechanism as a very natural possible explanation for the baryon asymmetry of the Universe. The explicit realization of this mechanism depends on the neutrino…
Stimulated by a universal seesaw mass matrix model which can successfully give quark masses and CKM matrix elements in terms of charged lepton masses, the evolution of the seesaw mass matrices is investigated. Especially, an investigation…
We study a supersymmetric SO(10) gauge theory in six dimensions compactified on an orbifold. Three sequential quark-lepton families are localized at the three fixpoints where SO(10) is broken to its three GUT subgroups. Split bulk…
The implementation of the Type III seesaw mechanism for neutrino masses in the context of left-right theories where parity is broken spontaneously is investigated. We propose a simple left-right symmetric theory where the neutrinos masses…
We discuss a supersymmetric unified model based on a product gauge group SU(5)\times SU(5)\times SU(5), where the gauge symmetry breaking is achieved without the adjoint or higher-dimensional Higgs field, and the doublet-triplet splitting…
The Standard Model includes neutrinos as massless particles, but neutrino oscillations showed that neutrinos are not massless. A simple extension of adding gauge singlet fermions to the particle spectrum allows normal Yukawa mass terms for…
We show that assuming fermion generations to be given by a gauge symmetry plus a certain Higgs mechanism for its breaking, the known empirical features of quark and lepton mixing can be largely explained, including in particular the fact…
We apply the discrete S_3 flavor symmetry to both lepton and quark sectors of the standard model extended by introducing one Higgs triplet and realizing the type-II seesaw mechanism for finite neutrino masses. The resultant mass matrices of…
We consider the minimal 3-3-1 model with a heavy scalar sextet and realize, at the tree level, an effective dimension-five interaction that contributes to the mass of the charged leptons. In this case the charged leptons masses arise from a…
We propose a realistic A4 extension of the Standard Model involving a particular quark-lepton mass relation, namely that the ratio of the third family mass to the geometric mean of the first and second family masses are equal for down-type…
The idea of quark-lepton universality at high energies has recently been explored in unified theories based upon the quartification gauge group SU(3)^4. These schemes encompass a quark-lepton exchange symmetry that results upon the…
We propose a lepton seesaw model to get the same mass-origin of charged-leptons and neutrinos introducing a modular $A_4$ symmetry. In this scenario, the mass matrix of charged-leptons is induced via seesaw-like mechanism while the mass…
We propose a new $\mathrm{SU}(3)_C \otimes \mathrm{SU}(2)_{L}\otimes \mathrm{U}(1)_{Y}\otimes \mathrm{U}(1)_{X}$ gauge model which is non universal respect to the three fermion families of the Standard Model. We introduce additional one…
Recent neutrino data have been favourable to a nearly bimaximal mixing, which suggests a simple form of the neutrino mass matrix. Stimulated by this matrix form, a possibility that all the mass matrices of quarks and leptons have the same…
We study fermion masses and mixing angles, including the generation of a seesaw mechanism for the neutrinos, in extended technicolor (ETC) theories. We formulate an approach to these problems that relies on assigning right-handed $Q=-1/3$…
Two models incorporating different forms of spontaneously broken quark-lepton symmetry are discussed. Both models are constructed so that quark-lepton symmetry can be broken at as low an energy scale as phenomenology allows, thus maximising…