Issue 6, 1974
Dissipative structures in a model for a chemical reaction with diffusion
Dissipative structures in a model for a chemical reaction with diffusion
M.S. Polyakova
Spatially periodic stationary solutions (dissipative structures) are considered for a model of a chemical reaction with diffusion; relationships are obtained between the amplitude of the dissipative structure and the wavelength, and the stability is also examined.
Show AbstractSelf-excited oscillations in spatially distributed biogeocenoses
Self-excited oscillations in spatially distributed biogeocenoses
V.V. Alekseev
Equations are derived to describe the behavior of communities of animals and plants in space and time; it is shown that the population density function takes the form of traveling waves in the linear approximation if the shifts in the environment are neglected and if there is a Yolterra interaction between species in the predator-prey system. A uniform distribution of the population densities in space is stable if there is a closed circulation of material.
Show AbstractApplication of percolation theory to the jump conductivity of a disordered sehiconductor
Application of percolation theory to the jump conductivity of a disordered sehiconductor
I.P. Zvyagin
A percolation problem arises in calculating the jump conductivity of a disordered semiconductor, and this is considered as determination of the critical density of the bonds between centers ϑc. Exact limits are obtained for the critical mean bond density, and an approximation calculation is performed via the procedure that takes into account the energy dependence of the mean number of bonds for an individual center.
Show AbstractThe contribution of collective modes in the target nucleus to the imaginary part of the optical potential
The contribution of collective modes in the target nucleus to the imaginary part of the optical potential
F.A. Zhivopistsev and E.S. Rzhevskii
Angular and energy relationships are examined for the part of the optical potential resulting from inelastic processes involving excitation of the lower collective states of the target; a comparison is made with the nonlocal Perey- Buck potential.
Show AbstractQuarks in astrophysics
Quarks in astrophysics
D.D. Ivanenko, D.F. Kurdgelaidze, and N.I. Maksyukov
A study is made of the basic parameters (including mass and radius) for equilibrium quark configurations having central densities from 10^{19} to 10^{32} g/C m^3; it is found that such objects should have large gravitational mass defects. It is assumed that quarks can recombine into hyperons, and it is shown that the number of recombined quarks is of the order of the total number of quarks in a star, the ratio of the number of free quarks to the recombined ones being 10^{-6}.
Show AbstractNonlinear representations of the lie algebra for the lorentz group (nondegenerate series)
Nonlinear representations of the lie algebra for the lorentz group (nondegenerate series)
N.F. Nelipa and I.B. Chervyakov
Nonlinear representations are derived for the Lie algebra of the Lorentz group (nondegenerate series), and invariants of the representation are constructed; it is shown that the dimensions of the maximal irreducible representation are 6.
Show AbstractTheory of emission from a point charged particle moving in parallel electric and magnetic fields
Theory of emission from a point charged particle moving in parallel electric and magnetic fields
A.B. Kukanov
The charged point particle moves in steady homogeneous parallel electric and magnetic fields; an analytic expression is derived for the total radiation energy incorporating polarization effects. A particular case is considered for motion in a steady and homogeneous electric field.
Show AbstractCorrect formulation of synthesis problems in waveguide synthesis
Correct formulation of synthesis problems in waveguide synthesis
A.G. Sveshnikov and T.A. Martynova
Rigorous formulation of synthesis problems is considered; the synthesis problem is considered for a particular waveguide device. The results from a numerical experiment are presented and analyzed.
Show AbstractRadiation friction in the motion of an electron in steady crossed electric and magnetic fields
Radiation friction in the motion of an electron in steady crossed electric and magnetic fields
A.M. Voloshchenko
Expressions are derived for the 4-velocity and path incorporating the radiation friction when an electron moves in mutually perpendicular electric and magnetic fields equal in magnitude. It is found that the solution differs from the exact one for the Lorentz-Dirac equation by a quantity less than the quantum corrections.
Show AbstractCascade theory for low energies of the primary displaced atom
Cascade theory for low energies of the primary displaced atom
B.Ya. Yurkov
The multiparticle interaction of atoms in a lattice corresponds to an approximation involving continuous energy loss by an atom moving through the lattice. The solution to the Lewis-Spencer equation gives the energy distribution of the atoms of generation m, and also the number of these atoms for the threshold formation energy for a radiation defect. The calculations agree well with results obtained by Vineyard's method.
Show AbstractMatched filtration of transient signals with tuned gravitational detectors
Matched filtration of transient signals with tuned gravitational detectors
V.A. Burov and О.V. Dmitriev
Matched filtration is considered for the electrical signals derived from the mechanical vibrations of high-Q tuned gravitational-radiation detectors. It is assumed that the gravitational perturbation is a pulse. The results are extended to pulses of finite duration.
Show AbstractNonlinear parametric excitation of even harmonics in a tuned circuit
Nonlinear parametric excitation of even harmonics in a tuned circuit
M.D. Karasev, E.Yu. Smirnova, and A.N. Senin
The parametric excitation mechanism is examined for even harmonics in a seriestuned circuit with a reactive nonlinearity having a characteristic of odd type. The calculated results are compared with experiment.
Show AbstractPath integration for an electron in a random field
Path integration for an electron in a random field
V.L. Bonch-Bruevich and A.G. Mironov
Peynman's method of continual integration is applied to an electron in a random field; the ranges of application of the various approximations are elucidated. Green's functions and the state density are calculated with quantum corrections.
Show AbstractA cosmological model for space-time with torsion
A cosmological model for space-time with torsion
V.N. Ponomarev
A simple nontrivial example is considered for space-time with torsion, namely an isotropic and homogeneous universe. It is shown that the torsion effect is an effect of curvature type.
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