10,734 research outputs found
Ternary numbers and algebras. Reflexive numbers and Berger graphs
The Calabi-Yau spaces with SU(m) holonomy can be studied by the algebraic way
through the integer lattice where one can construct the Newton reflexive
polyhedra or the Berger graphs. Our conjecture is that the Berger graphs can be
directly related with the -ary algebras. To find such algebras we study the
n-ary generalization of the well-known binary norm division algebras, , , , , which helped to discover the
most important "minimal" binary simple Lie groups, U(1), SU(2) and G(2). As the
most important example, we consider the case , which gives the ternary
generalization of quaternions and octonions, , , respectively. The
ternary generalization of quaternions is directly related to the new ternary
algebra and group which are related to the natural extensions of the binary
algebra and SU(3) group. Using this ternary algebra we found the
solution for the Berger graph: a tetrahedron.Comment: Revised version with minor correction
The Fermion Generations Problem in the Gust in the Free World-Sheet Fermion Formulation
In the framework of the four dimensional heterotic superstring with free
fermions we present a revised version of the rank eight Grand Unified String
Theories (GUST) which contain the -gauge family symmetry. We also
develop some methods for building of corresponding string models. We explicitly
construct GUST with gauge symmetry and or
and consider the full massless spectrum for our string models.
We consider for the observable gauge symmetry the diagonal subgroup
of the rank 16 group or . We discuss the possible fermion matter and Higgs sectors in
these theories. We study renormalizable and nonrenormolizable contributions to
the superpotential. There has to exist "superweak" light chiral matter () in GUST under consideration. The understanding of quark and lepton mass
spectra and family mixing leaves a possibility for the existence of an
unusually low mass breaking scale of the family gauge symmetry (some
TeV).Comment: 68 page
Transition between ordinary and topological insulator regimes in two-dimensional resonant magnetotransport
In the two-dimensional case the transition between ordinary and topological
insulator states can be described by a massive Dirac model with the mass term
changing its sign at the transition point. We theoretically investigate how
such a transition manifests itself in resonant transport via localized helical
edge states. The resonance occurs in the middle of the band gap due to a zero
edge-state mode which is protected by the time-reversal symmetry, also when
coupled to the conducting leads. We obtain the explicit dependence of the
resonant conductance on the mass parameter and an external magnetic field. The
proposal may be of practical use, allowing one to determine the orbital
g-factor of helical edge states in two-dimensional topological insulators.Comment: 7 pages, 3 eps figures, Phys. Rev. B (in press
Pion Polarizability in the NJL model and Possibilities of its Experimental Studies in Coulomb Nuclear Scattering
The charge pion polarizability is calculated in the Nambu-Jona-Lasinio model,
where the quark loops (in the mean field approximation) and the meson loops (in
the approximation) are taken into account. We show that quark loop
contribution dominates, because the meson loops strongly conceal each other.
The sigma-pole contribution plays the main role and
contains strong t-dependence of the effective pion polarizability at the region
. Possibilities of experimental test of this sigma-pole
effect in the reaction of Coulomb Nuclear Scattering are estimated for the
COMPASS experiment.Comment: 11 pages, 8 figure
The processes in the extended NJL model
The process is described in the framework of
the extended NJL model. Intermediate vector mesons ,
and \rho'(1450)e^{+}e^{-}
\to \pi\pi'(1300)\rho'(1450)$ meson.Comment: 7 pages, 5 figure
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