5,418 research outputs found
Triangular decomposition of right coideal subalgebras
Let be a Kac-Moody algebra. We show that every homogeneous
right coideal subalgebra of the multiparameter version of the quantized
universal enveloping algebra containing all
group-like elements has a triangular decomposition , where and are right coideal
subalgebras of negative and positive quantum Borel subalgebras. However if and are arbitrary right coideal subalgebras of respectively
positive and negative quantum Borel subalgebras, then the triangular
composition is a
right coideal but not necessary a subalgebra. Using a recent combinatorial
classification of right coideal subalgebras of the quantum Borel algebra
we find a necessary condition for the triangular
composition to be a right coideal subalgebra of
If has a finite multiplicative order similar results remain valid
for homogeneous right coideal subalgebras of the multiparameter version of the
small Lusztig quantum groups $u_q(\frak{so}_{2n+1}).
Properties of spatial arrangement of V-type defects in irradiated materials: 3D-modelling
We consider the dynamics of pattern formation in a system of point defects
under sustained irradiation within the framework of the rate theory. In our
study we generalize the standard approach taking into account a production of
defects by elastic fields and a stochastic production representing internal
multiplicative noise. Using 3D-modelling we have shown that with the damage
rate growth, a morphology of clusters composed of vacancies changes. The same
effect is observed with variation in the multiplicative noise intensity.
Stationary patterns are studied by means of correlation analysis.Comment: 12 pages, 7 figure
Ab-initio calculations for structural properties of Zr-Nb alloys
Ab-initio calculations for the structural properties of Zr-Nb alloys at
different values of the niobium concentration are done at zero temperature.
Different cases for Zr-Nb alloys with unit cells having BCC and HCP structures
are considered. Optimal values of the lattice constants are obtained. Critical
value for the niobium concentration corresponding to the structural
transformation HCP \rightarrow BCC at zero temperature is determined.
Electronic densities of states for two different structures with niobium
concentrations 12.5% and 25% having HCP and BCC structures, accordingly, are
studied.Comment: 8 pages, 4 figure
Three-body treatment of the penetration through the Coulomb field of a two-fragment nucleus
On the basis of the Faddeev integral equations method and the Watson-
Feshbach concept of the effective (optical) interaction potential, the first
fully consistent three-body approach to the description of the penetration of a
charged particle through the Coulomb field of a two-particle bound complex
(composed of one charged and one neutral particles) has been developed. A
general formalism has been elaborated and on its basis, to a first
approximation in the Sommerfeld parameter, the influence of the nuclear
structure on the probability of the penetration of a charged particle (the
muon, the pion, the kaon and the proton) through the Gamow barrier of a
two-fragment nucleus (the deuteron and the two lightest lambda hypernuclei,
lambda hypertriton and lambda hyperhelium-5, has been calculated and studied.Comment: LaTeX, 30 pages, 4 eps figure
Universality and self-similar behaviour of non-equilibrium systems with non-Fickian diffusion
Analytical approaches describing non-Fickian diffusion in complex systems are
presented. The corresponding methods are applied to the study of statistical
properties of pyramidal islands formation with interacting adsorbate at
epitaxial growth. Using the generalized kinetic approach we consider
universality, scaling dynamics and fractal properties of pyramidal islands
growth. In the framework of generalized kinetics, we propose a theoretical
model to examine the numerically obtained data for averaged islands size, the
number of islands and the corresponding universal distribution over the island
size.Comment: 10 pages, 6 figure
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