3,698 research outputs found
Neutrino Mass Matrix and Hierarchy
We build a model to describe neutrinos based on strict hierarchy,
incorporating as much as possible, the latest known data, for
and , and for the mixing angles determined from neutrino
oscillation experiments, including that from KamLAND. Since the hierarchy
assumption is a statement about mass ratios, it lets us obtain all three
neutrino masses. We obtain a mass matrix, and a mixing matrix, ,
where both and are given in terms of powers of , the
analog of the Cabibbo angle in the Wolfenstein representation, and
two parameters, and , each of order one. The expansion
parameter, , is defined by 0.16, and expresses our ignorance
of the lightest neutrino mass ), while
scales to the experimental upper limit, . These matrices are similar in structure to those for the
quark and lepton families, but with about 1.6 times larger than the
for the quarks and charged leptons. The upper limit for the effective
neutrino mass in double -decay experiments is if
and if is maximal. The model, which
is fairly unique, given the hierarchy assumption and the data, is compared to
supersymmetric extension and texture zero models of mass generation.Comment: 8 pages, LaTex, This paper updates an earlier version by
incorporating KamLAND dat
Integrable Anisotropic Evolution Equations on a Sphere
V.V. Sokolov's modifying symmetry approach is applied to anisotropic
evolution equations of the third order on the n-dimensional sphere. The main
result is a complete classification of such equations. Auto-B\"acklund
transformations are also found for all equations.Comment: Published in SIGMA (Symmetry, Integrability and Geometry: Methods and
Applications) at http://www.emis.de/journals/SIGMA
European Cyber Security System
Nowadays computer networks are widely spread in all spheres of human life.
That is why the problem of cyber security of mankind is of great importance. Today,
the European Union makes efforts to guarantee network safety in Europe by means of
increase its member states in power and international cooperation in cyber security,
including non-member countries, to prevent cyber crimes. Striving to join the
European Union, Ukraine is involved in the process of providing cyber security. This
paper examines the main strategies of EU standards in cyber security to be followed
by Ukraine as one of European countries
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