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
The paper studies boundary value problems for second order quasilinear elliptic equations in divergence form on a composite domain divided by an internal interface. It formulates Schauder type a priori estimates for a corresponding linear problem with conjugation conditions on the interface and an o…
This paper studies Hausdorff symmetrizable spaces through weak epsilon-maps and epsilon-maps onto auxiliary spaces. It proves that a sequence of continuous weak 1/n-maps induces an embedding into the product of the target spaces, and that closed 1/n-maps yield a homeomorphism onto the image, giving …
This note derives an exact solution for a frictionless contact problem involving ideal elastic-plastic bodies in plane stress that satisfy the Tresca-Saint-Venant yield condition. The argument shows that plastic regions occur as zero-thickness lines on the contact boundary in the more plastic body, …
This paper examines ultrafast modulation of semiconductor quantum generator radiation by heating the electron-hole gas with intense optical radiation, thereby reducing population inversion and gain without changing the number of active carrier pairs. Using rate equations for photons and nonequilibri…
This paper analyzes relaxation in a near-resonant two-level quantum system driven by a monochromatic external field whose phase changes randomly, a situation relevant to radiation broadened by collisions. Using density-matrix equations and a phase-space distribution method for Poisson-distributed ph…
This paper formulates boundary-value problems for the continuum theory of dislocations in an anisotropic elastic medium. Using generalized functions concentrated on volumes, surfaces, and contours, it derives a Green formula for internal stresses and applies it to dislocation sources, including volu…
This study examines the defects responsible for Tyndall scattering and clouding in synthetic quartz containing a so-called nonstructural impurity. Synthetic quartz grown in sodium carbonate solutions was studied by electron microscopy using self-shadowed carbon replicas of fracture surfaces, before …
This paper analyzes a proposed radiation-driven instability in a bounded, thermodynamically nonequilibrium plasma when the radiation density is below the Planck value and emitted radiation is not trapped. Using simplified energy-balance equations for hydrogen plasma with negligible thermal conductiv…
This paper formulates an extremal thermoelasticity problem for an infinite isotropic cylindrical shell subjected to an axisymmetric temperature field that is uniform through the thickness and vanishes at infinity. The elastic strain energy is minimized under prescribed values of displacement-related…
This paper studies the local behavior near the origin of a nonautonomous system of differential equations whose nonlinear term is small in a Lipschitz sense, comparing it with the corresponding linear system with constant matrix. Extending earlier one-sided asymptotic results to functions defined fo…
This paper studies admissibility of Monte Carlo cubature procedures for square integrable functions, using variance domination as the criterion within a specified class of unbiased randomized procedures. For procedures based on determinant ratios associated with a finite orthonormal bounded system, …
The note extends A. N. Kolmogorov’s uniform approximation theorem for sums of independent identically distributed variables to partial sums of random variables forming a homogeneous Markov chain under an exponential ergodicity condition. The proof uses Bernstein’s blocking method to separate the sum…
For a hyperbolic equation of the form $$U_{tx}=f(t,x,U(t,x),U(t-\tau,x),U_t(t,x),U_t(t-\tau,x),U_x(t,x)U_x(t-\tau,x))$$ with an initial function $\varphi(t,x)$ defined for $(t,x)\in[t_0-\tau_0,t_0]\times\Omega$ and with a delay $\tau=\tau(t,x,U,U_t,U_x)$ that depends not only on the independent vari…
This paper studies generators for perfect partitions in ergodic theory, focusing on ergodic automorphisms of Lebesgue spaces with finite entropy. Building on results of Rokhlin and Sinai, it proves by a direct construction that any perfect partition for such an automorphism has a countable generator…
This paper studies cyclic invariant subspaces of bounded dissipative operators in a separable Hilbert space whose spectrum is concentrated at zero and whose resolvent growth satisfies a logarithmic bound. Using a universal model built from a direct sum of simple Volterra dissipative operators and it…
This paper derives convergence rate estimates for projection type approximations to elliptic boundary value problems with positive definite self-adjoint differential operators of order 2k. Using a variational framework, it constructs approximating spaces based on regular cellular subdivisions, diffe…
The paper considers an automatic control system with a variable structure, described by a system of third-order differential equations, the parameters of which vary within wide limits. A cone located in the phase space of variables $x_1$, $x_2$, $x_3$ is taken as the switching surface. The switching…
The paper derives an explicit transformation for polynomial sums of iterated operators of the form \(t^\alpha D\), where \(D\) denotes differentiation and the powers \(t^\alpha\) are taken on fixed branches. It gives coefficients expressing such operator sums as ordinary differential operators with …
Electron paramagnetic resonance spectra were measured at 4.2 K for low-temperature glasses containing rare-earth ions, chiefly neodymium and cerium compounds, at 300 to 400 MHz and 9500 MHz. The study finds intense low-frequency signals for all examined Nd3+ and Ce3+ glasses, while high-frequency si…
This paper estimates subsurface temperatures for a planned 15 km ultradeep borehole in the Saatly region of the southeastern Caucasus. Using a geothermal gradient expression that incorporates surface heat flow, radiogenic heat generation, layer thicknesses, and rock thermal conductivity, the study c…
The paper studies multidimensional integral operators on domains in Euclidean space whose kernels are homogeneous of order minus the dimension, with attention to weighted Banach spaces of bounded, continuous, and integrable functions. Under rotational invariance and explicit summability conditions o…
This paper studies conditions under which infinite solvable, generalized solvable, and nilpotent groups contain proper infinite subgroups preserving the same derived length or nilpotency class. It introduces the notions of stably solvable and stably nilpotent groups, proves that infinite solvable or…
This paper examines the physical mechanism of anomalously large photovoltages in semiconductor films under monochromatic illumination, focusing on whether the AFN effect arises from micro p-n junctions or from photodiffusion Dember processes. The authors argue that angular dependences of the photovo…
This paper studies singular Cauchy and Tricomi problems for second-order hyperbolic equations with coefficients singular on the coordinate axes, including equations with constant and variable perturbing terms. Using Riemann functions, Green-Hadamard resolvents, and special functions such as Humbert,…
This editorial article commemorates the fiftieth anniversary of the October Revolution by presenting the development of Soviet science as a result of socialist organization, state planning, and the integration of theoretical, applied, and technical research. It argues that science became an essentia…
A system of differential equations containing angular coordinates is considered. The phase space of such a system is cylindrical. Based on the behavior of trajectories on covering spaces, a classification of the trajectories of the system under consideration is introduced. Conditions for the absence…
The paper studies positive periodic solutions of a nonlinear second-order differential equation with periodic coefficients, nonnegative nonlinearity, and a nonoscillation assumption on the associated linear equation. Using cone-theoretic methods, it gives sufficient conditions for the existence of n…
This paper generalizes Chebyshev’s integral inequality from one variable to functions of several variables with a nonnegative weight. It proves that the weighted inequality over every subdomain holds if and only if the two functions are functionally dependent and one is a nondecreasing function of t…
The system of differential equations \begin{gather}\theta=x,\notag\\\dot{x}=-\alpha x-\frac{g}{l}\sin\theta+y^2\sin\theta\cos\theta+L,\tag{1}\\\dot{y}=-\alpha y+2xy\operatorname{ctg}\notag\theta\end{gather} is investigated using Lyapunov functions. It is shown that for $0<\alpha<2\sqrt{\frac{q}{l}}$…
The paper studies the applicability of numerical algorithms for linear functional equations that approximate the underlying spaces and operator by finite-dimensional ones and then solve the resulting systems by triangular factorization without reordering. It formulates a correspondence condition lin…
This study examines spectral evidence for donor, acceptor interactions between organic adsorbates and the surface of the hole semiconductor TlJ. Electron donor and electron acceptor molecules were adsorbed from vapor under high vacuum onto degassed TlJ, and changes in capacitor photo-emf, photocondu…
This note derives a generating function for the eigenvalues of Casimir operators associated with irreducible representations of classical groups. Starting from previously obtained formulas for these eigenvalues, the authors express them through a product formula involving the shifted highest weights…
The paper develops Schauder-type estimates for solutions of higher-order elliptic equations and systems under general boundary conditions in spaces with refined Hölder exponents. It introduces function classes defined by moduli of the form r to the alpha of r, proves interior estimates for Douglis-N…
This note proposes an iterative method for linear and quadratic programming problems with nonnegativity inequalities and linear equality constraints, extending the method of steepest descent to constrained extremal problems. For linear programming, the method defines dual estimates through a weighte…
This paper develops an axiomatic framework for nonrenormalizable quantum field theories whose momentum-space quantities may have growth beyond the tempered distributions of Schwartz-space formulations. It proposes using fields as operator-valued analytic functionals over the Fourier-Laplace transfor…
This note revisits the asymptotic expansion method for a weakly interacting nonideal Bose-Einstein system in a modified formulation with independent parameters for the condensate number and chemical potential. It analyzes correction terms to the thermodynamic potential, particle number, and chemical…
The paper studies plane adiabatic supersonic flow of an ideal gas past a smooth convex symmetric profile with a detached shock wave, focusing on the neighborhood of a sonic point on the contour. Using characteristic relations, entropy monotonicity near the critical streamline, and hodograph-plane ma…
This study examines the spectral dependence of photoionization of sensitizing centers in cadmium sulfide and addresses why impurity photoconductivity spectra measured at equal photon flux differ strongly among samples. The authors analyze relaxation kinetics of impurity photocurrent under steady int…
This paper reports experimental observations of premature termination, or self-quenching, of generation in a ruby optical quantum generator when transparent liquids or solids are placed in the resonator, and under high-loss resonator conditions even without added media. Using ruby crystals with vari…
This paper develops a framework for spatial mappings with bounded distortion in Euclidean space using conformal norms, Sobolev class assumptions, Jacobians, and local degree. It defines distortion coefficients for linear and Sobolev mappings, proves continuity and almost everywhere differentiability…
This paper examines whether superconducting-type pair correlations can arise in the pi-electron systems of polycyclic aromatic molecules, treating them as finite Fermi systems. It argues that effective attraction between pi-electrons may be produced by coupling to molecular vibrations or by virtual …
This paper investigates the crystal structures of cobalt(III) pentaammine complexes containing an inner-sphere thiocyanato group, with nitrate, chloride, or thiocyanate counterions. Using X-ray diffraction methods, including Fourier refinement for the nitrate salt and powder or limited single-crysta…
This paper derives a four-dimensional formulation for electromagnetic potentials in a medium that may be anisotropic, dispersive, and moving, using Fourier amplitudes of the field tensors and Tamm’s material tensor. The authors introduce a tensor construction that transforms the field equations into…
This paper reports experiments on cooperative sensitization of luminescence in silver halide salts and photographic emulsions treated with dye sensitizers. Low-temperature excitation spectra show that short-wavelength silver halide luminescence can be produced by red and infrared light absorbed in t…
This note studies best approximation of finite and infinite sets by elements of a convex subset of a Banach space, using convex monotone functionals to measure approximation error. It introduces support functionals at generalized points, that is, minimizing sequences, and proves criteria characteriz…
The problem of electromagnetic field diffraction by a spheroid is solved. The source of the primary field is a magnetic dipole located on the polar axis of the spheroid. The dipole moment is directed at a right angle to the axis; the spheroid is perfectly conducting. The solution to the problem is r…
