4,896 research outputs found
On Invariants of Quark and Lepton Mass Matrices in the Standard Model
In this article I present the motivation for introducing the invariant
functions of mass matrices, based on my own work, and give some examples. Since
their introduction in 1985, in the framework of the standard electroweak model,
they have been used by many authors. Some authors have gone further along this
path and have studied the extensions of this concept to frameworks beyond the
standard model. I hope, in the near future, to give a more detailed account of
this subject, including recent developments
The quark mixing matrix with manifest Cabibbo substructure and an angle of the unitarity triangle as one of its parameters
The quark mixing matrix is parameterised such that its "Cabibbo substructure"
is emphasised. One can choose one of the parameters to be an arbitrarily chosen
angle of the unitarity triangle, for example the angle (also called
)
The Role of Invariant Functions in Understanding Masses and Mixings
One of the central questions in theoretical particle physics, since already
several decades, has been that of "masses and mixings of the quarks. With the
entry of neutrino oscillations into the field, the issue of lepton masses has
added a new dimension to the problem. In the literature one finds many models
of quark and lepton mass matrices. However, the mass and mixing problems remain
unsolved.
In this talk I will present my own contributions to this field, however as
you may expect without offering a solution. I encourage you to go ahead and
think about the problem but be aware of the pitfalls.Comment: Talk presented at the conference SNOW 200
Ambiguities pertaining to quark-lepton complementarity
Recently the possible origin of the so-called quark-lepton complementarity
relations has received a considerable amount of attention. We point out some of
the inherent ambiguities in such analyses
Recursive parameterisation and invariant phases of unitary matrices
We present further properties of a previously proposed recursive scheme for
parameterisation of n-by-n unitary matrices. We show that the factors in the
recursive formula may be introduced in any desired order. The method is used to
study the invariant phases of unitary matrices. The case of four-by-four
unitary matrices is investigated in detail. We also address the question of how
to construct symmetric unitary matrices using the recursive approach
A recursive parameterisation of unitary matrices
A simple recursive scheme for parameterisation of n-by-n unitary matrices is
presented.Comment: Notations simplified and more details give
Supersymmetry - Roots That Didn't Grow
This article is about early roots of supersymmetry, as found in the
literature from 1940s and early 1950s. There were models where the power of
"partners" in alleviating divergences in quantum field theory was recognized.
However, other currently known remarkable features of supersymmetry, such as
its role in the extension of the Poincar\'{e} group, were not known. There
were, of course, no supersymmetric non-abelian quantum field theories in those
days
Invariants of Lepton Mass Matrices and CP and T Violation in Neutrino Oscillations
CP and T asymmetries in neutrino oscillations, in vacuum as well as in
matter, are expressed in terms of invariant functions of lepton mass matrices.Comment: 9 page
Neutrino Sector with Majorana Mass Terms and Friedberg-Lee Symmetry
We examine a recently proposed symmetry/condition by Friedberg and Lee in the
framework where three right-handed neutrinos are added to the spectrum of the
three-family Minimal Standard Model. It is found that the right-handed
neutrinos are very special, with respect to this symmetry. In the symmetry
limit the neutrinos are massless and that may be a hint about why they are
light. Imposed as a condition and not as a full symmetry, we find that one of
the three right-handed neutrinos simply decouples (has only gravitational
interactions) and that there is a massless interacting neutrino. The possible
relation of the model to the see-saw mechanism is briefly discussed
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