Related papers: Deviation from Bimaximality due to Planck scale ef…
We discuss renormalization effects on neutrino masses and mixing angles in a supersymmetric string-inspired SU(4) X SU(2)_L X SU(2)_R X U(1)_X model, with matter in fundamental and antisymmetric tensor representations and singlet Higgs…
We analyse how a large value of the leptonic mixing angle \theta_{13}^{MNS} can be generated via charged lepton corrections in unified flavour models, using novel combinations of Clebsch-Gordan factors for obtaining viable quark-lepton mass…
Neutrino mixing matrix appears to be close to bimaximal mixing, but for the solar mixing angle which is definitively smaller than forty five degrees. Whereas it seems quite easy to understand bimaximal mixing with the use of new global…
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…
In models with a low quantum gravity scale, one might expect sizable effects from nonrenormalizable interactions that violate the global symmetries of the standard model. While some mechanism must be invoked in such theories to suppress…
We advocate the idea that proton decay may probe physics at the Planck scale instead of the GUT scale. This is possible because supersymmetric theories have dimension-5 operators that can induce proton decay at dangerous rates, even with…
Two-loop effects on the right-handed neutrino masses can have an impact on the low-energy phenomenology, especially when the right-handed neutrino mass spectrum is very hierarchical at the cut-off scale. In this case, the physical masses of…
The neutrino mixing matrix U is in general of the form U=U_e^+ U_nu, where U_e arises from the diagonalization of charged leptons and U_nu is from the neutrino sector. We discuss the possibility that U_nu is nearly diagonal (in the…
Freedom from global anomalies in the presence of a local SU(2)_H horizontal symmetry under which right handed charged leptons transform nontrivially requires that there be at least two right handed neutrinos with masses of order of the…
Considering a general mass matrix for quasi-degenerate neutrinos and treating the experimentally known oscillation parameters as inputs, we study the correlation between the degenerate mass scale $(m)$ and the mixing angle $\theta_{13}$. We…
Majoron models provide neutrino masses via the spontaneous breaking of a global $U(1)$ symmetry. However, it may be argued that all global symmetries will be explicitly violated by gravitational effects. We show that it is possible to…
We propose a simple but suggestive seesaw model with two phenomenological conjectures: three heavy (right-handed) Majorana neutrinos are degenerate in mass in the symmetry limit and three light Majorana neutrinos have the tri-bimaximal…
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…
The observed pattern of neutrino mixing may be the result of a 2-3($ \mu- \tau$) symmetry in the leptonic sector. We consider a two Higgs doublet model with a 2-3 symmetry in the down type quark and the charged lepton sector. The breaking…
The recent results from T2K and MINOS experiments point towards a relatively large value of the reactor angle \theta_13 in the lepton sector. In this paper we show how a large \theta_13 can arise from the charged lepton sector alone in the…
GUT scale threshold corrections in minimal SU(5) supergravity grand unification are discussed. It is shown that predictions may be made despite uncertainties associated with the high energy scale. A bound relating the strong coupling…
We study perturbations of exactly tri-bimaximal neutrino mixings under the assumption that they are coming solely from the charged lepton mass matrix. This may be plausible in scenarios where the mass generation mechanisms of neutrinos and…
Physics beyond the standard model of electroweak interactions that violates lepton number will, in general, induce operators involving the quark and lepton fields that violate lepton number. I point out that some matrix elements of…
Environmental decoherence of oscillating neutrinos of strength $\Gamma = (2.3 \pm 1.1) \times 10^{-23}$ GeV can explain how maximal $\theta_{23}$ mixing observed at 295 km by T2K appears to be non-maximal at longer baselines. As shown…
Compared to the other neutrino mixing angles \theta_{13} is small. The solar mass splitting is about two orders smaller than the atmospheric splitting. We show that it is possible that both are perturbative effects on a more symmetric…