Related papers: A Mass Spectrum for Leptons and Quarks
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…
Leptoquarks are known to generate a wide range of potentially observable phenomena, and have been searched for in different experiments. We show that the observed baryon asymmetry and neutrino mass scale can both be simultaneously produced…
Masses and mixings of quarks and leptons differ wildly from one another. Thus it is all the more challenging to search for some hidden attribute that they may share.
For some time the measured value of tau-lepton mass continues to approach closer and closer a particular figure 1776.80 MeV predicted by an intrinsically composite model of three generations of leptons and quarks, introduced almost two…
The successful A4 family symmetry for leptons is applied to quarks, motivated by the quark-lepton assignments of SU(5). Realistic quark masses and mixing angles are obtained, in good agreement with data. In particular, we find a strong…
In theories in which the parameters of the low energy theory are not unique, perhaps having different values in different domains of the universe as is possible in some inflationary models, the fermion masses would be distributed with…
In this letter we present a model for quarks and leptons based on T7 as flavour symmetry, predicting a canonical mass relation between charged leptons and down-type quarks proposed earlier. Neutrino masses are generated through a Type-I…
We summarize the results showing that all existing data on mixing between up and down fermion states (i.e. CKM matrix and neutrino oscillations) and on the hierarchical quark and lepton mass ratios between generations are consistent with…
The quark-lepton mass problem and the ideas of mass protection are reviewed. The Multiple Point Principle is introduced and used within the Standard Model to predict the top quark and Higgs particle masses. We discuss the lightest family…
The new quantum number is introduced. It is shown that the conservation of -number results in the conservation of difference between baryon and lepton numbers. The problem of quark-lepton symmetry is discussed. It is shown that the nature…
The pattern of quark and lepton mass matrices is unexplained in the standard model of particle interactions. I propose the novel idea of a progressive gauge U(1) symmetry where it is a reflection of the regressive electroweak symmetry…
A recent parameterisation scheme developed for the quark mixing matrix is shown to be easily applicable to the lepton mixing matrix as well.
Phenomenological implications of a class of lepton mass matrices with parallel texture structure have been examined and phenomenologically interesting constraints on charged lepton and neutrino mass matrix parameters have been obtained.
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…
Recent measurements of the neutrino solar mixing angle and the Cabibbo angle satisfy the empirical relation theta_{sol} + theta_{C} ~ 45^{o}. This relation suggests the existence of a correlation between the mixing matrices of leptons and…
We propose a realistic A4 extension of the Standard Model involving a particular quark-lepton mass relation, namely that the ratio of the third family mass to the geometric mean of the first and second family masses are equal for down-type…
We relate leptogenesis in a class of theories to low-energy experimental observables: quark and lepton masses and mixings. With reasonable assumptions motivated by grand unification, one can show that the CP-asymmetry parameter takes a…
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 origin of quark and lepton masses is one of the outstanding problems of physics. As the experimental data becomes more and more accurate, testing theories of fermion masses requires greater care. In this talk we discuss a theoretical…
It has been recognized recently that there is a remarkable empirical relation between lepton and quark mixing angles, theta_{12} + theta_C \approx pi/4. If not accidental, it should testify for yet uncovered new relationship between the…