17 research outputs found
Nonextensivity in Geological Faults?
Geological fault systems, as the San Andreas fault (SAF) in USA, constitute
typical examples of self-organizing systems in nature. In this paper, we have
considered some geophysical properties of the SAF system to test the viability
of the nonextensive models for earthquakes developed in [Phys. Rev. E {\bf 73},
026102, 2006]. To this end, we have used 6188 earthquakes events ranging in the
magnitude interval that were taken from the Network Earthquake
International Center catalogs (NEIC, 2004-2006) and the Bulletin of the
International Seismological Centre (ISC, 1964-2003). For values of the Tsallis
nonextensive parameter , it is shown that the energy
distribution function deduced in above reference provides an excellent fit to
the NEIC and ISC SAF data.Comment: 9 pages, 1 figure, standard LaTeX fil
Neutrino masses from operator mixing
We show that in theories that reduce, at the Fermi scale, to an extension of
the standard model with two doublets, there can be additional dimension five
operators giving rise to neutrino masses. In particular there exists a singlet
operator which can not generate neutrino masses at tree level but generates
them through operator mixing. Under the assumption that only this operator
appears at tree level we calculate the neutrino mass matrix. It has the Zee
mass matrix structure and leads naturally to bimaximal mixing. However, the
maximal mixing prediction for solar neutrinos is very sharp even when higher
order corrections are considered. To allow for deviations from maximal mixing a
fine tuning is needed in the neutrino mass matrix parameters. However, this
fine tuning relates the departure from maximal mixing in solar neutrino
oscillations with the neutrinoless double beta decay rate.Comment: 11 pages, 1 figure, revte