Related papers: Correlated Hierarchy, Dirac Masses and Large Mixin…
We derive formulae for neutrino masses and mixing angles in a type I seesaw framework with an underlying A4 flavor symmetry. In particular, the Majorana neutrino mass matrix includes contributions from an A4 triplet, 1, 1', and 1" flavon…
The high scale mixing unification hypothesis recently proposed by three of us (R. N. M., M. K. P. and G. R.) states that if at the seesaw scale, the quark and lepton mixing matrices are equal then for quasi-degenerate neutrinos, radiative…
The pattern of lepton mixing can emerge from breaking a flavor symmetry in different ways in the neutrino and charged lepton Yukawa sectors. In this framework, we derive the conditions imposed on the mixing matrix by the structure of…
In the light of the recent measurement of the leptonic mixing angle $\theta_{13}$, implications of the latest mixing data have been investigated for non-minimal textures of lepton mass matrices pertaining to Dirac neutrinos. All these…
After developing a general criterion for deciding which neutrino mass models belong to the category of inverse seesaw models, we apply it to obtain the Dirac analogue of the canonical Majorana inverse seesaw model. We then generalize the…
In the vortex background on a sphere, a single 6-dimensional fermion family gives rise to 3 zero-modes in the 4-dimensional point of view, which may explain the replication of families in the Standard Model. Previously, it had been shown…
Lepton mixing can originate from the breaking of a flavor symmetry in different ways in the neutrino and the charged lepton sector. We propose an extension of this framework which allows to connect the mixing parameters with masses, and…
In these notes, we review the main results of our approach to fermion masses. The marge mass ratios between fermions, confronted with a unique breaking mechanism leading to vector bosons masses, led us to consider the possibility that they…
The lepton masses and mixings are studied on the basis of string inspired $SU(6)\times SU(2)_R$ model with global flavor symmetries. Provided that sizable mixings between lepton doublets $L$ and Higgsino-like fields $H_d$ with even R-parity…
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 propose a seesaw scenario that possible corrections to the tribimaximal pattern of lepton mixing are due to the small phase splitting of the right-handed neutrino mass matrix. we show that the small deviations can be expressed…
If the scale dependence of a Yukawa matrix is assumed to be determined entirely by the dominant 33-element, then the renormalization group equations can be expressed in terms of two separate equations: a differential equation for the…
A beautiful understanding of the smallness of the neutrino masses may be obtained via the seesaw mechanism, whereby one takes advantage of the key qualitative distinction between the neutrinos and the other fermions: right-handed neutrinos…
Models involving a U(2) flavor symmetry, or any of a number of its non-Abelian discrete subgroups, can explain the observed hierarchy of charged fermion masses and CKM angles. It is known that a large neutrino mixing angle connecting second…
An explicit model of neutrino texture is presented, where in the 6 times 6 mass matrix the Majorana lefthanded component is zero, the Majorana righthanded component - diagonal with equal entries, and the Dirac component gets a hierarchical…
Models with composite singlet neutrinos can give small Majorana or Dirac masses to the active neutrinos. The mechanism is based on the fact that conserved chiral symmetries give massless neutrinos at the renormalizable level. Thus, they…
We introduce three right-handed Majorana neutrinos and combine the type-I seesaw and inert doublet mechanisms. The resultant (active) neutrino mass matrix is divided into rank=1 and =2 parts with different energy scales. The different…
We show that the large mixing between $\nu_\mu$ and $\nu_\tau$ observed by the SuperKamiokande collaboration is a quite natural prediction in a large class of seesaw models. This large mixing is basically due to the unparallel family…
Model-independent consequences of applying a generalized hidden horizontal Z_2 symmetry to the neutrino mass matrix are explored. The Dirac CP phase delta_D can be expressed in terms of the three mixing angles as 4 c_a s_a c_s s_s s_x cos…
Understanding the disparate mixing patterns between quarks and leptons is one of the major challenges in particle theory today. I discuss some of the ways to understand this difference within the seesaw framework using new symmetries of…