Related papers: Can Randomness lead to non-anarchical mixing angle…
Hermitian squared mass matrices of charged leptons and light neutrinos in the flavor basis are studied under general additive lowest order perturbations away from the tribimaximal (TBM) limit in which a weak basis with mass diagonal charged…
Neutrino masses and mixings are analyzed in terms of left-handed fields and a 6x6 complex symmetric mass matrix whose singular values are the neutrino masses. An angle x_nu characterizes the kind of the neutrinos, with x_nu = 0 for Dirac…
Motivated by the absence of signals of new physics at the LHC, which seems to imply the presence of large mass hierarchies, we investigate the theoretical possibility that these could arise dynamically in new strongly-coupled gauge theories…
In this talk I review the present status of neutrino masses and mixing and some of their implications for particle physics phenomenology. I first discuss the minimum extension of the Standard Model of particle physics required to…
We propose a radiative seesaw model in alternative left-right model without any bidoublet scalar fields, in which all the fermion masses in the standard model are generated through a canonical seesaw mechanism at the tree level. On the…
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…
The minimal supersymmetric standard model (MSSM) of particle interactions is extended to include three singlet (right-handed) neutrino superfields together with three other singlet superfields. The resulting theory is assumed to be…
This work proposes two models of neutrino masses that predict non-zero $\theta_{13}$ under the non-Abelian discrete flavor symmetry $\mathbb{S}_3\otimes\mathbb{Z}_2$. We advocate that the size of $\theta_{13}$ is understood as a group…
We discuss a class of models of neutrino masses and mixings with inverse hierarchy based on a broken U(1)_F flavour symmetry with charge L_e-L_\mu-L_\tau for lepton doublets and arbitrary right-handed charges. The symmetry breaking sector…
In dense neutrino environments, such as provided by core-collapse supernovae or neutron-star mergers, neutrino angular distributions may be unstable to collective flavor conversions, whose outcome remains to be fully understood. These…
We address two fundamental aspects of flavor physics: the mass hierarchy and the large lepton mixing angles. On one side, left-right flavor symmetry realizes the democratic mass matrix patterns and explains why one family is much heavier…
A simple mechanism to generate Dirac masses for the neutrinos in SU(5) supersymmetric grand unified theory is proposed. The tiny Dirac masses are induced by the small mixing between the Higgs fields and another superheavy fields. The mixing…
A new idea for neutrino mass was proposed recently, where its smallness is not due to the seesaw mechanism, i.e. not inversely proportional to some large mass scale. It comes from a one-loop mechanism with dark matter in the loop consisting…
We consider a minimal extension of the Standard Model which advocates a dark neutrino sector charged under a hidden $U(1)^\prime$. We show that neutrino masses can arise radiatively in this model. The observed values are compatible with a…
The discrete flavor symmetry A4 explains very well neutrino data at low energy, but it seems difficult to extend it to grand unified models since in general left-handed and right-handed fields belong to different A4 representations.…
We consider the possibility that the quark condensate formed by QCD confinement generates Majorana neutrino masses m_\nu via dimension seven operators. No degrees of freedom beyond the Standard Model are necessary, below the electroweak…
The Tri-bimaximal (TBM) mixing is not accidental if structures of the corresponding leptonic mass matrices follow immediately from certain (residual or broken) flavor symmetry. We develop a simple formalism which allows one to analyze…
Motivated by the Super-Kamiokande data, we revisit models with U(1) symmetries and discuss the origin of neutrino masses and mixings in such theories. We show that, in models with just three light neutrinos and a hierarchy of neutrino…
We introduce a new parameterisation of the effect of unknown corrections from new physics on quark and lepton mass matrices. This parameterisation is used in order to study how the hierarchies of quark masses and mixing angles are modified…
A structure is proposed for the mass matrices of the quarks and leptons that arises in a natural way from the assumption that the breaking of SO(10) gauge symmetry is achieved by the smallest possible set of vacuum expectation values. This…