Related papers: Tachyonic neutrinos?
We apply a new approach based on three relativistic groups (bradyon, tachyon and instanton) forming the `Lorentz groupoid' which allows, in particular, to consider tachyons without introducing imaginary masses and negative energies…
The mass matrices of charged fermions have a simple structure if expressed in powers of the small parameter sigma=(m_c/m_t)^{1/2}. It is suggested that the mass matrix of the three heavy neutrinos occuring in grand unified theories can be…
New data on neutrino masses is very exciting. It is the first evidence for physics beyond the standard model. In this talk we discuss this data and how it may (or may not) be used to constrain theories of charged fermion masses. The talk is…
In the standard approach to the neutrino oscillations a unitary relation among weak and mass eigenstates of light neutrinos is imposed. However, in many extensions of the SM left-handed, active neutrinos mix with additional heavy neutrino…
In this talk I review the `puzzles' associated with the fermion mass matrices and describe some recent attempts to resolve them, at least partially. Models which attempt to explain the observed mass hierarchy as arising from radiative…
A non-supersymmetric grand unified theory can exhibit a "radiative fermion mass hierarchy", in which the heavier quarks and leptons get mass at tree level and the lighter ones get mass from loop diagrams. Recently the first predictive model…
Motivated by the recent SuperKamiokande results on atmospheric neutrinos, we incorporate massive neutrinos, with large angle oscillation between the second and third generations, in a theory with R-parity violating supersymmetry. The…
A group theoretical understanding of the two dimensional fractional supersymmetry is given in terms of the quantum Poincare group at roots of unity. The fractional supersymmetry algebra and the quantum group dual to it are presented and the…
Some of basic problems in neutrino physics such as new energy scales, the enormous gap between neutrino masses and the lightest charged fermion mass, possible existance of sterile neutrinos in eV mass range are studied in the local gauge…
The group E_6 for grand unification is combined with the generation symmetry group SO(3) x Z(2). The coupling matrices in the Yukawa interaction are identified with the vacuum expectation values of scalar flavons. The symmetric part of this…
It is firmly established by experimental results that neutrinos are almost 100\% longitudinally polarized and left-handed. It is also confirmed by neutrino oscillation experiments that neutrinos have tiny but non-zero masses. Since their…
Extensions of the Standard Model with additional U(1) symmetries can describe the hierarchy of fermion masses and mixing angles, including neutrinos. The neutrino masses and mixings are determined up to a discrete ambiguity corresponding to…
We use the Whittaker vectors and the Drinfeld Casimir element to show that eigenfunctions of the difference Toda Hamiltonian can be expressed via fermionic formulas. Motivated by the combinatorics of the fermionic formulas we use the…
The hypercharges of the fermions are not uniquely determined in SO(10) grand unification, but rather depend upon which linear combination of the two U(1) subgroups of SO(10) > SU(3) X SU(2) X U(1) X U(1) remains unbroken. We show that, in…
We compare the structures and methods in the theory of causal fermion systems with approaches to fundamental physics based on division algebras, in particular the octonions. We find that octonions and, more generally, tensor products of…
Quark lepton universality inherent in grand unified theories based on $SO(10)$ gauge group generically leads to hierarchical neutrino masses. We propose a specific ansatz for the structure of Yukawa matrices in $SO(10)$ models which differ…
Neutrino oscillation experiments presently suggest that neutrinos have a small but finite mass. If neutrinos are to have mass, there should be a Lorentz frame in which they can be brought to rest. This paper discusses how Wigner's little…
We study holonomy groups coming from F-theory compactifications. We focus mainly on SO(8) as 12-4=8 and subgroups SU(4), Spin(7), G2 and SU(3) suitable for descent from F-theory, M-theory and Superstring theories. We consider the relation…
We constrain generic nonstandard neutrino interactions with existing experimental data on neutrino transition magnetic moments and derive strong bounds on tensorial couplings of neutrinos to charged fermions. We also discuss how some of…
The relevance of the data concerning upward--going muons for the solution of the atmospheric neutrino problem is stressed. In particular, their inclusion in the analysis confirms the goodness of the neutrino oscillation hypothesis and…