Related papers: Universal 2-3 symmetry
We study a number of models, based on a non-Abelian discrete group, that successfully reproduce the simple and predictive Yukawa textures usually associated with U(2) theories of flavor. These models allow for solutions to the solar and…
We consider the oscillations of atmospheric neutrinos in the earth in the three-neutrino scheme with a $\Delta m^2$ hierarchy and a small admixture of the electron neutrino in the heavy mass eigenstate characterized by the mixing angle…
We apply the permutation symmetry S_3 to both charged-lepton and neutrino mass matrices, and suggest a useful symmetry-breaking scheme, in which the flavor symmetry is explicitly broken down via S_3 -> Z_3 -> nothing in the charged-lepton…
We review the problem of neutrino masses and mixings in the context of Grand Unified Theories. After a brief summary of the present experimental status of neutrino physics, we describe how the see-saw mechanism can automatically account for…
Assuming high-energy tri-bi-maximal mixing we study the radiative running of leptonic mixing angles and obtain limits on the high-energy scale from requiring consistency with the observed mixing. We construct a model in which a non-Abelian…
The observed neutrino mixing, having a near maximal atmospheric neutrino mixing angle and a large solar mixing angle, is close to tri-bi-maximal. This structure may be related to the existence of a discrete non-Abelian family symmetry. In…
The present neutrino oscillation data allow $m^{}_1 = 0$ (or $m^{}_3 = 0$) for the neutrino mass spectrum and support $\theta^{}_{23} \simeq \pi/4$ and $\delta \simeq -\pi/2$ as two good approximations for the PMNS lepton flavor mixing…
We find that the presence of a global $L_e-L_\mu-L_\tau$ ($\equiv L^\prime$) symmetry and an $S_2$ permutation symmetry for the $\mu$- and $\tau$-families supplemented by a discrete $Z_4$ symmetry naturally leads to almost maximal…
Recent solar & atmospheric nu-data strongly indicate need for physics beyond the Standard Model. I review the ways of reconciling them in terms of 3-nu oscillations. Though not implied by data, bi-maximal nu-mixing models emerge as a…
The existence of two sterile neutrinos $\nu_s$ and $\nu'_s$ (blind to all Standard-Model interactions) is shown to be implied by a model of fermion "texture" that we develop since some time. They may mix nearly maximally with two of three…
We show how a unified description of the various two-flavor neutrino oscillation solutions, allowed by the atmospheric and solar neutrino experiments, are naturally realized within the framework of $\nu$MSSM (MSSM augmented with the seesaw…
New data from neutrino oscillation experiments motivate us to extend a successful mass relation for the charged leptons to the other fundamental fermions. This new universal relation requires a Dirac mass around 3 10^-2 eV for the lightest…
We show that all mixing angles are determined, within experimental uncertainty, by a product of SU(2) horizontal symmetries intimately linked to the algebra of weak neutral currents. This concerns: on one hand, the three quark mixing…
We develop a detailed and comprehensive description of neutrino oscillations driven by the 1-3 mixing in the matter of the Earth. The description is valid for the realistic (PREM) Earth density profile in the whole range of nadir angles and…
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…
The $\mu$-$\tau$ exchange symmetry in the neutrino mass matrix and its breaking as a perturbation are discussed. The exact $\mu$-$\tau$ symmetry restricts the 2-3 and 1-3 neutrino mixing angles as $\theta_{23} = \pi/4$ and $\theta_{13} = 0$…
After some preliminary arguments suggesting that neutrino mixings with inverted mass pattern may be easier to understand within the framework of a local horizontal symmetry SU(2)_H acting on leptons, we construct a specific extension of the…
We identify a plausible scenario based on quark-lepton symmetry which correlates long baseline oscillations with maximal mixing to sterile neutrinos. The implication for the Sudbury Neutrino Observatory (SNO) is that the neutral current…
Recent results from SuperKamiokande and SNO experiments have set severe constraints on possible mixings of a light sterile neutrino, \nu_s, with the three active species required for a simultaneous explanation of the solar, atmospheric and…
We exam the pairs of neutrino mixing matrix and suggest pairs that can be used in the construction of new mixing patterns, with "pair" denoting the equality of the modulus of a pair of matrix elements. The results show that the tri-maximal…