SovietRxiv · Open Access in English
Rediscovering the Soviet scientific archive, in English
25357 full-text translations 14926 English PDFs 22539 abstracts
Showing 50 of 25357 papers
This paper studies complete solvability and reducibility for linear multidimensional differential equations in finite-dimensional Banach spaces with continuous, and later almost periodic, operator coefficients. It gives necessary and sufficient conditions for complete solvability in terms of a rotor…
This paper examines the coordinate-space representation of the pairing interaction used in the superfluid model of the nucleus, where pairing is introduced between nucleons in the last unfilled shell. Starting from the second-quantized Hamiltonian, it derives the corresponding configuration-space ke…
This note refines a limit theorem for the number of classes of purely radical quadratic forms of negative determinant. Using a generalized Esseen inequality, estimates for averages of complex powers of Dirichlet L-functions, Bombieri’s density theorem as applied by Barban, and Rogozin’s concentratio…
This paper studies decoding automata for memoryless encodings that can self-adjust after input substitution errors, certain state failures, and, in a generalized finite case, shifts of the input sequence. It introduces semibounded and \((l,m)\)-semibounded automata, characterizes them through comple…
This paper derives a quantum statistical expression for the spin diffusion coefficient in spin systems treated as weakly interacting subsystems, such as Zeeman, dipole, or exchange reservoirs. Using Zubarev’s nonequilibrium statistical operator in the high temperature approximation, the authors form…
The paper introduces and analyzes a boundary value problem for the degenerating hyperbolic equation y^m u_xx minus u_yy equals zero in a characteristic domain, with data prescribed on the line of degeneracy and a fractional derivative relation imposed on the characteristic boundary. Using the Darbou…
This paper develops an alternative theory of the electronic structure of cyclic molecules in which strong Coulomb repulsion makes tunneling of one pi electron through another negligible, producing a one-dimensional Wigner chain that undergoes hindered rotation relative to the molecular framework. Th…
This note addresses several questions on perfectly normal bicompact spaces, especially nonmetrizable examples and mapping properties. It constructs a nonmetrizable perfectly normal bicompact admitting an open countably multiple map onto the Cantor set, and, assuming the continuum hypothesis, a conne…
This paper studies the flow of entry times of a stationary time-homogeneous Markov process into a measurable subset of the phase space from its complement. It introduces a basic conditional mean measure for entries and proves, under convergence and regularity assumptions, an asymptotic formula for t…
This note studies maximal resolvability of products of topological spaces, addressing a question about whether known product theorems for maximally resolvable spaces extend to other natural product topologies. Using dense families of subsets, dispersion character, and cardinal estimates for products…
This paper examines the relation between meteor luminosity and ionization using simultaneous photographic and radar observations conducted in Dushanbe for seven Leonid and Perseid meteors. The study derives absolute photographic magnitudes and initial linear electron densities of meteor trails, acco…
This paper studies the motion of a centrally symmetric medium with velocities close to the speed of light within general relativity. Starting from the relativistic hydrodynamic and field equations, it assumes an ultrarelativistic equation of state and expands for small deviations from light speed, i…
This paper studies estimation of regression coefficients in a discrete-time Gaussian process with a deterministic linear regression component and stationary noise. It introduces and analyzes “pseudobest” unbiased estimates, defined as maximum-likelihood estimates computed using a chosen pseudospectr…
The paper develops a statistical mechanical treatment of weakly nonideal partially ionized hydrogen consisting of atoms, protons, and electrons under Debye screened Coulomb interactions. Using a grand canonical ensemble expressed in terms of physical groups, it separates bound and free proton electr…
This paper presents a qualitative method for analyzing second-order nonlinear dynamical systems by transforming the governing equations to a canonical form involving characteristic functions determined from a functional characteristic equation. The approach relates the real parts of these characteri…
This paper examines whether ion-induced amorphization of crystals can be used to assess the relative importance of cascade and focused-collision mechanisms in cathode sputtering. The authors argue that comparing sputtering from crystalline and amorphous phases of the same substance offers a relative…
This note studies boundary value problems for higher order singular elliptic equations with constant and variable coefficients involving the Bessel operator in a quarter-space. Using explicit fundamental solutions, generalized shift operators, Poisson kernels, and the Lopatinskii complementing condi…
This paper studies the gravitational stability of spherically symmetric stationary solutions of the collisionless dust cloud equations, with distribution functions depending on particle energy and satisfying a monotonicity condition. The authors formulate the linearized problem through a self-adjoin…
This note studies finite separability in semigroups, distinguishing semigroups whose arbitrary subsets can be separated from exterior points by homomorphisms onto finite semigroups from those where only subsemigroups are required. It gives a general necessary and sufficient criterion in terms of fin…
This paper studies self-similar nonlinear waves in an ultrarelativistic ideal gas with equation of state energy density equal to three times the pressure, under spherical and cylindrical symmetry. The Cauchy problem is reduced to an ordinary differential equation for the dimensionless velocity, with…
This paper analyzes inviscid flows of a dissociating homonuclear diatomic gas when local thermodynamic equilibrium is not assumed. It formulates the governing equations with finite dissociation and recombination rates, derives frozen and equilibrium sound speeds, and examines one-dimensional steady …
This paper addresses the need for photographic materials with higher resolving power and suitable laser sensitivity for holographic recording. The authors describe the development of a high resolution silver halide emulsion, IAE-1, with microcrystals averaging about 250 Å, and evaluate it against th…
This paper studies summability and boundedness properties of solutions to a class of hypoelliptic constant coefficient equations in unbounded domains, under quasi-homogeneity assumptions on the characteristic polynomial and absence of nonzero real characteristic zeros. It introduces function spaces …
This study reports photoelectric Raman measurements for tetramethylsilane and a series of methylchlorosilanes, determining fundamental frequencies, peak and integral intensities, half-widths, depolarization degrees, corrected scattering coefficients, and polarizability-derivative tensor invariants. …
The paper studies the Cauchy problem for the Laplace equation with analytic data by analytically continuing the equation, the data, and the Cauchy surface into a complex domain. For three and four variables, it constructs local integral representations of the holomorphic solution using the character…
This paper formulates models of material continuous media in special relativity using a variational principle that allows piecewise smooth fields with finite discontinuities on hypersurfaces. For a Lagrangian depending on higher derivatives of medium parameters and the motion, it derives generalized…
The paper develops a duality theory for locally convex topological vector groups over the real or complex field endowed with the discrete scalar topology. It establishes Hahn-Banach type separation results, weak closure properties, and a characterization of compatible locally convex vector space top…
The paper investigates charge states of krypton atoms produced by electron capture of radioactive rubidium in rubidium fluoride, chloride, and bromide matrices, using the Mössbauer emission spectra of the 9.3 keV transition in krypton-83. Resonance spectra were measured at selected temperatures and …
This note develops refinements of a Tauberian theorem of M. V. Keldysh concerning the recovery of asymptotic information on increasing functions from integral transforms. Under assumptions on the behavior of Stieltjes or ordinary integral transforms in a complex region bounded by a curve, the author…
This paper analyzes amplitudes of core-reflected PcP waves from atomic explosions to reassess the reflection coefficient at the core mantle boundary and its implications for Earth structure. Using about 60 explosion records, including cases where PcP was not identifiable, the authors model amplitude…
This note studies approximately optimal properties of Wald tests for testing statistical hypotheses in parametric families under regularity conditions on the likelihood and its derivatives. It estimates the accuracy of Wald’s asymptotic optimality results by proving normal approximation and concentr…
This paper investigates nonequilibrium processes behind strong shock waves in nitrogen and air, with attention to vibrational excitation, dissociation, and associated changes in refractive index. Using a shock tube and a quantitative shadow photoelectric method, the authors determine gradients of re…
Ytterbium films condensed onto liquid-helium-cooled glass substrates were studied through temperature-dependent electrical resistance measurements during controlled warming. Seventeen films with thicknesses from 240 to 18000 Å showed a sharp resistance decrease near 14 K for layers thinner than abou…
The paper examines transient processes in convective systems, emphasizing the mutual adjustment of convective elements and the surrounding stratified medium. Using a laboratory model with weakly miscible water and aniline layers heated or cooled under controlled conditions, it observes the developme…
The paper studies polynomial approximation in the mean on the boundary for analytic functions in Smirnov classes \(E_p\), \(p>1\), on simply connected domains whose rectifiable Jordan boundary belongs to a class defined by boundedness of the Cauchy singular integral in \(L_p\). Using a generalized m…
This paper studies the sharpness of known upper estimates for the convergence of derivatives of Lagrange and Hermite interpolation polynomials on Chebyshev type nodes for functions whose first derivative has a prescribed modulus of continuity. It constructs, for each degree, special functions in the…
This paper studies how regularity properties behave under products of the form Phi(f(x))f'(x), in contrast with the often worse behavior of the superposition Phi(f(x)). It proves that if Phi is absolutely continuous and f is differentiable with absolutely continuous derivative, then Phi(f(x))f'(x) i…
This note establishes necessary and sufficient conditions for a boundary point to be regular for the Dirichlet problem for a uniformly parabolic second-order equation with bounded Hölder coefficients in an arbitrary domain. Using Wiener’s method of generalized solutions and a parabolic potential ass…
This note studies differential games in which one player seeks to drive the state of a nonlinear controlled system to a closed terminal set in minimum time while the other seeks to prevent it. To avoid difficulties caused by discontinuous positional strategies, the paper introduces sigma strategies,…
This paper reports tests of the large Pulkovo variable-profile reflector radio telescope after replacement of its flat reflecting panels with cylindrical elements to permit operation in the 8 to 9 mm wavelength range. Using geodetic, radio range-finding, ground-source, and astronomical adjustment me…
This paper extends earlier results on finite projection spectra of topological spaces to infinite spectra formed from directed families of decompositions and partitions, using nerves of coverings and their limit spaces. It introduces completeness relative to a family of decompositions, analyzes spac…
This paper investigates whether alkali halide crystal phosphors can be prepared by surface treatment rather than by activation during melt growth. Freshly cleaved KCl and NaCl crystals were treated with aqueous thallium nitrate or copper sulfate solutions, annealed, quenched, and examined by absorpt…
This paper reports regular meter-wave observations of the pulsar CP-1919 made from April to July 1968 with the DKR-1000 radio telescope at Pushchino, mainly near 93 MHz with additional measurements from 61 to 110 MHz. The authors analyze frequency-dependent pulse delays, intensity variations, pulse-…
The paper studies homogeneous locally symmetric domains in generalized conformal spaces of signature \((p,q)\), reducing their classification to the algebraic problem of determining suitable defining planes in the Lie algebra of the conformal transformation group. It proves that every such plane is …
This paper studies metric criteria for functional series whose coefficients range over Banach spaces of numerical sequences, emphasizing situations where classical results such as Landau’s theorem do not apply because convergence is only almost everywhere or in measure. It gives necessary and suffic…
The paper studies singularly perturbed systems of ordinary differential equations in which a small parameter multiplies the derivatives of the fast variables, focusing on cases where the associated fast system has a degenerate equilibrium or a degenerate limit cycle. Under specified nondegeneracy an…
This paper reexamines the pressure assigned to the polymorphic transformation in iron, a commonly used reference point for calibrating high-pressure apparatus. The authors compare earlier pressure scales and prior measurements, then measure the room-temperature electrical resistance of high-purity c…
