Related papers: Finite Mixing Angles in the Standard Model
In the simplest examples of models with a discrete quark-lepton symmetry, an electroweak symmetry breaking sector with more than one Higgs doublet is necessary to obtain the correct mass relations between quarks and leptons. A two Higgs…
Guided by considerations of flavour symmetry, we construct a set of exact Standard Model (SM) renormalisation group evolution invariants which link quark masses and mixing parameters. We examine their phenomenological implications and infer…
In the quark sector, we experience a correlation between the mixing angles and the mass ratios. A partial realization of the similar tie-up in the neutrino sector helps to constrain the parametrization of masses and mixing, and hints for a…
In view of the fact that the data on neutrino mixing are still compatible with a situation where Bimaximal mixing is valid in first approximation and it is then corrected by terms of order of the Cabibbo angle, we present examples where…
We explore the hypothesis that the Cabibbo angle is an expansion parameter for lepton as well as quark mixing. Cabibbo effects are deviations from zero mixing for the quarks but are deviations from unknown mixings for the leptons, such that…
Two semi-empirical ideas are guiding the present research: 1) one neutrino and N color quark triple mixing angles have second physical meaning of vector direction angles in euclidean 3-space, and 2) the difference between neutrino and quark…
We propose an extension of the Standard Model by extending the EW symmetry to SU(2)_L x U(1) x Z_2 and introducing three SU(2)_L x U(1) singlet right handed neutrinos, N_R, and an additional Higgs doublet, phi. While the SM gauge bosons and…
The standard model of leptons is extended to accommodate a discrete Z_3 X Z_2 family symmetry. After rotating the charged-lepton mass matrix to its diagonal form, the neutrino mass matrix reveals itself as very suitable for explaining…
An extension of the Standard Model (SM) based on the non-Abelian discrete group $\Delta(27)$ is considered. The $\Delta(27)$ flavour symmetry is spontaneously broken only by gauge singlet scalar fields, therefore our model is free from any…
We study the implications of having a similarity between quark and lepton mixing in the Dirac sector of the Standard Model plus the right-handed neutrino. This enable us to describe all masses and mixings in the Dirac sector in terms of…
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…
From two different modifications of the Gell-Mann-Okubo mass relation for (1/2)^+ baryons: the first one given by a version of diquark-quark model and the second one being the optimal mass sum rule obtained by using quantum groups U_q(su_n)…
We study systematically the possibility for realizing realistic values of quark mass ratios $m_c/m_t$ and $m_s/m_b$ and the mixing angle $V_{cb}$ by using only renormalizable Yukawa couplings derived from heterotic orbifold models. We…
We study the implications of a large nu_mu - nu_tau mixing angle on flavour changing transitions of quarks and leptons in supersymmetric extensions of the standard model. Two patterns of supersymmetry breaking are considered, models with…
We study an extension of the standard model based on the flavor symmetry A4 only. Neutrino Majorana mass terms arise from dimension five operator and charged lepton masses from renormalizable Yukawa couplings. We introduce three Higgs…
We construct phenomenological quark-lepton mass matrices based on S$_3$ permutation symmetry in a manner fully compatible with SU(5) grand unification. The Higgs particles we need are {\bf 5}, {\bf 45} and their conjugates. The model gives…
We propose several Two Higgs Doublet Models with the addition of an Abelian gauge group which free the usual framework from flavor changing neutral interactions and explain neutrino masses through the seesaw mechanism. We discuss the…
We discuss systematically the fermion mass and mixing matrices in a generic \linebreak field-theoretical flipped $SU(5)$ model, with particular applications to neutrino and baryon number-changing physics. We demonstrate that the different…
We extend the standard model with two extra Higgs doublets. Making use of a symmetry principle, we present flavour symmetries based on cycle groups $Z_N$ that oblige each Higgs doublet to contribute to the mass of only one generation, thus…
We develop a model of ours fitting the quark and lepton masses and mixing angles by removing from the model a Higgs field previously introduced to organise a large atmospheric mixing angle for neutrino oscillations. Due to the off-diagonal…