Chronicle

Winners of the Stalin Prize for 1949

A number of works in the fields of physics, astrophysics, physical chemistry, and technical physics were awarded Stalin Prizes for 1949.

The first-degree Prize was awarded to the President of the Academy of Sciences of the Armenian SSR, Director of the Byurakan Astrophysical Observatory, V. A. Ambartsumian, and to the senior scientific associate of the same observatory, B. E. Markarian, for the discovery and study of a new type of stellar systems (“stellar associations”), set forth in a series of articles published in the journals Communications of the Byurakan Observatory, Proceedings of the Academy of Sciences of the Armenian SSR, and Astronomical Journal in 1949.

The very discovery of the existence of previously unnoticed systems of stars is of exceptionally great importance, all the more so because this is not a matter of an accidental discovery, but of the correct interpretation of previously known observations of separate, scattered facts. Widely dispersed stellar groups (“stellar associations”), singled out by the commonality of certain physical characteristics—for example, variable brightness of a special type, or the presence of emission lines in the spectrum that indicate the ejection of matter—turned out to be genetically connected, unified systems of stars. In a short time a significant number of such stellar associations were discovered.

The cosmological aspect of the works under consideration is of great significance. The authors have shown with great clarity that, because the spatial concentration of stars within these associations is much lower than that of stars in the general stellar field of the Galaxy, the systems under consideration are unstable and must be destroyed under the action of the tidal influence of the general field of attraction of the Galaxy. As a result, the members of an association disperse in space. The fact that these stellar associations are nevertheless observed indicates that they were formed recently and that the stars in them have not yet had time to disperse. Therefore the age of such associations cannot exceed one hundred million years, which is very small in comparison with the age of the Galaxy—of the order of several billion years. Not only the stellar associations themselves, but also the stars contained in these associations, are of the same age—of the order of ten million years. The formation of stellar associations and the formation of stars within them is taking place continuously at the present time. Thus the idealistic notions of the origin of the universe as a single act are definitively refuted.

The works of V. A. Ambartsumian on stellar associations establish a new, very fruitful direction in cosmogony and in stellar astronomy.

The first-degree prize was also awarded to Academician G. A. Shain—for spectral investigations of stellar atmospheres, culminating in the discovery in them of an anomalous content of the heavy isotope of carbon, set forth in a series of articles published in the journals Izvestiya Krymskoi Astrofizicheskoi Observatorii and Doklady Akademii nauk SSSR in 1948–1949.

Academician G. A. Shain is responsible for a large number of major discoveries in the field of stellar spectroscopy. He was the first to prove the rotation of a number of stars about their axes. He also produced one of the best catalogs in the world, in terms of accuracy of modern catalogues, of radial velocities of stars, compiled from his observations together with Albitsky at the Simeiz Observatory. He discovered a large number of new spectroscopic binary stars. He has major works in the field of spectrography, in particular on the Balmer decrement in the spectra of stars with bright lines.

Even during the years of the Patriotic War, G. A. Shain published a study in which he showed for the first time that, alongside the ordinary bands of molecular carbon \(C_{12} C_{12}\), in “cold” stars we often also observe bands belonging to a molecule in which one atom is replaced by heavy carbon \(C_{13}\), i.e., bands of the molecules \(C_{12} C_{13}\).

Thus, it was demonstrated by direct observations that in stellar atmospheres both types of carbon atoms are present. But especially interesting are the works of G. A. Shain carried out in the last two years; in these works it is shown that the ratio of the intensities of the bands \(C_{13} C_{13}\) and \(C_{12} C_{13}\) in some stars is many times greater than the intensity ratio that would exist with the relative abundance of both isotopes that we have on Earth. It is sufficient to say that the observations of G. A. Shain led to the conclusion that in individual stars as many as one third of the carbon atoms have atomic weight 13.

It may be said that G. A. Shain’s discovery of \(C_{13}\) in stellar atmospheres and his establishment of an unusually high percentage of this carbon isotope constitute the largest investigation of isotopes in the atmospheres of celestial bodies.

In the field of physics, the second-degree prize was awarded to Professor of Leningrad State University named after A. A. Zhdanov M. V. Vol’kenshtein, Professor of the Leningrad Institute of Precision Mechanics and Optics M. A. El’yashevich, and Senior Research Associate of the State Optical Institute B. I. Stepanov for the monograph Molecular Vibrations in two volumes, published in 1949.

The two volumes of the monograph Molecular Vibrations constitute a fundamental work completing the authors’ many years of research.

The problem of the vibrations of a polyatomic molecule, and the associated problem of interpreting its infrared and combination spectra, has remained in an unsatisfactory state until the present time. A number of attempts in this direction, made by foreign physicists, did not lead to a successful solution of this problem. As a result of the work of Vol’kenshtein, El’yashevich, and Stepanov, a theory of the vibrational spectra of complex molecules has been created. This theory revealed the regularities of intramolecular vibrations manifested in infrared spectra and Raman spectra. In a number of cases it also makes it possible to predict the properties of complex molecules.

The monograph consists of five parts. The first and second parts examine the geometry and mechanics of molecular vibrations. These parts constitute a detailed exposition of the properties of the normal configuration, the symmetry of vibrations, methods for calculating the frequencies and forms of vibrations, and methods for determining the constants of potential energy.

A great merit of the authors of the monograph is that they have introduced a suitably chosen system of coordinates and created a new and simple method for composing secular equations, as a result of which they have succeeded in making methods for calculating frequencies of molecules extraordinarily effective. As a result, the constants of the potential energy of molecules have been calculated for a broad class of compounds, among which are paraffins, halogen-substituted paraffins, alcohols, ethers, amines, and some molecules with double bonds. Using examples of frequency calculations for more than 70 molecules, the authors demonstrate the enormous fruitfulness of their method, which makes it possible to understand, and sometimes to predict, frequencies in the spectra of very complex molecules with dozens of degrees of freedom.

The third part of the monograph, devoted to the electro-optics of vibrations, treats the question of the intensity and polarization of combination and infrared lines. The existing theory of line polarization, given by Placzek, has been considerably expanded by the authors.

Their great merit is the creation of an original method for calculating the intensity and polarization of combination and infrared lines, based on the assumption of the additivity of bonds and using quantities found in the study of other phenomena.

The fourth part of the monograph is devoted to physicochemical problems connected with molecular vibrations. Here chemical bonds, potential-energy constants, intermolecular interaction, the theory of the hydrogen bond, the thermodynamics of vibrations, and rotational isomerism are considered. All these questions are of extraordinary interest to a wide circle of physicists and chemists.

They are treated by the authors in an original way, and sometimes are solved by them in an entirely new manner.

The last part of the book outlines paths for the broad application in molecular-spectral analysis of the results obtained by the authors.

The applied significance of the work of Vol’kenshtein, El’yashevich, and Stepanov is undoubtedly very great. The study of the structure and properties of glass, both silicate and organic; the investigation of liquid fuel; the study of such substances as plastics, rubbers, polymers, whose importance in technology is constantly increasing—all this requires the application of spectroscopic methods of investigation. But these methods are effective only on the condition that the possibility has been established of completely interpreting the spectrum of a substance. This problem is solved by the profound theoretical analysis developed by the authors of the monograph.

Professors of Moscow State University named after M. V. Lomonosov, D. D. Ivanenko and I. A. Sokolov, and Doctor of Physical and Mathematical Sciences Yu. Ya. Pomeranchuk, have been awarded the Stalin Prize, second degree, for work on the theory of the “luminous electron” and on contemporary problems of electrodynamics, set forth in the monograph Classical Field Theory, published in 1949.

D. D. Ivanenko and Yu. Ya. Pomeranchuk showed that electrons moving at relativistic velocities in circular orbits in accelerators of the betatron type must radiate electromagnetic waves intensely. This conclusion, later fully confirmed by experiment, is of enormous practical importance, for, as the authors showed, it is precisely radiation losses that limit the attainable values of the energies of accelerated particles in a number of types of accelerators. The radiation spectrum was also subjected to detailed study. It turned out that the main share of the radiation energy falls on higher harmonics, including (under known conditions) the visible spectrum. The angular distribution of the radiation and a number of other effects were also investigated. In finished form the theory of the “luminous electron” is presented in the above-mentioned monograph by D. D. Ivanenko and I. A. Sokolov.

Central to the monograph are questions of the theory of elementary particles and intranuclear interactions from the point of view of classical field theory. The authors have succeeded in showing convincingly that many of the most important problems of the theory of the atomic nucleus and elementary particles can be successfully solved by applying the simplest classical methods, without resorting to complex quantum calculations.

In the first three chapters the fruitfulness of applying the delta function in solving the most varied problems of classical field theory is demonstrated.

The authors have created a universal method for solving problems in the theory of various fields.

In the fourth chapter, for the first time, the problems of the classical theory of the electron as an elementary particle are presented. The method developed in the first chapters is used for the theory of Cherenkov phenomena. In the monograph this theory is set forth in the simplest way.

Of particular interest is the fifth chapter, devoted to the most important problem of the atomic nucleus. It summarizes the authors’ principal investigations on the theory of the meson field and on questions of the justification of the neutron-proton model of the atomic nucleus, as well as on the theory of nuclear forces, the quantum theory of damping, and the quantum theory of gravitation.

The second prize in the field of technical sciences was awarded to Professor, Doctor of Physical and Mathematical Sciences, Corresponding Member of the Academy of Sciences of the Ukrainian SSR V. I. Danilov for his works on the crystallization of liquids and on the study of supercooling phenomena.

The main result of V. I. Danilov’s work is as follows. He established a law governing the formation of crystallization centers on the dispersed particles of insoluble impurities. It was shown that the influence of preliminary overheating of a liquid on the kinetics of crystallization is due to deactivation of impurities, and not to the temperature dependence of the atomic structure of the liquid. The phenomenon of impurity activation was discovered and studied. Thus a way was shown of regulating the behavior of particles of insoluble impurities.

By applying an improved method of purifying a substance from insoluble impurities, the author for the first time succeeded in showing the possibility of practically eliminating the influence of impurities and experimentally resolving the question of the possibility of observing so-called spontaneous nucleation of crystallization centers. The study of spontaneous crystallization in a large number of substances and low-melting metals made it possible to verify the theory of fluctuation nucleation of crystallization centers.

The author has given a method for determining physical constants (surface tension, activation energy) that characterize the crystallization kinetics of a given substance. For the first time experimental data were obtained on the magnitude of the surface tension at the liquid–crystal boundary for a number of substances.

Relying on fluctuation theory, V. I. Danilov comes to the conclusion that supercooled liquids freed from extraneous dispersed impurities can be divided, with respect to their capacity for spontaneous crystallization, into three categories.

1. Liquids of the type of lard, which do not possess the capacity for spontaneous crystallization at any temperatures. These liquids can be transformed into a glassy state at any cooling rates.

1. Liquids of the orthochloronitrobenzene type, to which also all metals belong, crystallizing spontaneously, but at all temperatures below the melting point.

Liquids of this type cannot be brought into a glassy state at any cooling rate.

1. Liquids of the piperine type, crystallizing spontaneously only within a certain temperature interval.

Liquids of this type can be brought into a glassy state at sufficiently high cooling rates.

V. I. Danilov substantiates these qualitative differences among supercooled liquids by quantitative relations among three quantities entering into the expression which the fluctuation theory gives for the rate of formation of crystallization centers. One of these quantities depends on the number of molecules in a unit volume of the liquid; another characterizes the energy of formation of a single nucleus; the third is the surface tension at the boundary between the crystal and the liquid.

The classification of supercooled liquids proposed by V. I. Danilov is undoubtedly a valuable contribution to science and can be usefully applied to crystallization technology.

A group of scientific workers (M. K. Grodzovsky, Kh. I. Kolodtsev, L. N. Khitrin, O. A. Tsukhanova), headed by Corresponding Member of the Academy of Sciences of the USSR A. S. Predvoditelev, was awarded the Stalin Prize, second degree, for theoretical and experimental investigations of the process of carbon combustion, presented in the monograph The Combustion of Carbon, published in 1949.

Relying on the basic concepts of the modern diffusion-kinetic theory of combustion, to a considerable extent common to the entire Soviet school of researchers in this field, the authors of the monograph for the first time examine a number of secondary phenomena that had previously received no systematic treatment but that inevitably accompany the basic process. Phenomena of this kind include first of all: the heterogeneous reduction of carbon dioxide, which at high temperatures changes from a secondary process into the principal one; the volumetric combustion of carbon monoxide, which significantly affects the rate at which oxygen is supplied to the surface of the carbon; and the transition of the process, at moderate temperatures, from the surface to the volume of the carbonaceous substance.

Taking these phenomena into account considerably refined the theory, brought it into closer agreement with experimental facts, and eliminated a number of ambiguities and formal contradictions that had accumulated in these facts.

The extraordinary complexity of the process, in which various physical and chemical factors interact, does not allow a completely precise mathematical description to be given. To simplify the system of differential equations, the authors introduce empirical constants that characterize both the properties of the reacting substances and the regime factors influencing the course of the process.

A careful examination of the results obtained in solving both internal (combustion of a carbon channel) and external (combustion of a carbon particle) diffusion problems, together with allowance for the basic principles of filtration theory, made it possible to pose an even more complex but practically especially important problem, concerning the case of combustion of an assemblage of carbon particles in the form of a bed. The method of calculation being developed, evidently, can be generalized to the case of combustion of pulverized carbon in a suspended state as well. All this is a very significant advance in the construction of the theory of combustion of solid fuel.

Chronicle

A number of physicists have been awarded Stalin Prizes for outstanding work in the field of invention.

Under the leadership of Academician V. P. Linnik, a series of optical instruments has been created for evaluating the cleanliness of surfaces and determining microhardness. In all, 7 instruments have been created, including interference microscopes, a small-size profilograph, a microinterferometer, an instrument for determining microhardness, and others.

Professor V. K. Prokofiev, senior research associate S. N. Sventitskii, and research associate K. I. Taganov have been awarded the Stalin Prize for the development and introduction into industry of new methods for the spectral analysis of metals and alloys. They proposed a method of sampling the substance under investigation for spectral analysis that uses electrospark transfer of the substance from the specimen being studied onto a preselected electrode. For the analysis an electrospark discharge is excited between the specimen and a permanent copper electrode.

The specimen is then removed and replaced by an electrode made of the same substance as the permanent one. An arc is ignited between them, and from the relative intensity of the spectral lines the concentration of the element sought is determined.

A large group of workers under the leadership of Professor P. G. Tager has been awarded the Stalin Prize for the development and introduction of new methods of sound recording for motion pictures.

Research associates Yu. G. Shafer, N. L. Grigorov, and A. S. Muratov have received the Stalin Prize for developing the design of apparatus for studying cosmic rays.

A group of associates under the leadership of V. K. Shembel created a new design of the state standard for reproducing the unit of frequency. The standard that was created, consisting of three generators of electrical oscillations with quartz frequency stabilization, ensures constancy of the oscillation frequency within two ten-billionths of a part per hour and two billionths of a part per day. In its qualitative indicators the frequency standard surpasses modern standards abroad.

B. L. Dzerzeevskii, E. M. Reikhrudel, Yu. A. Vinokur, and K. D. Bushev have been awarded the Stalin Prize for developing a new method of studying the atmosphere.

A group of authors headed by N. V. Viktorov, with the participation of D. I. Aronov, A. Sh. Shakhverdov, M. D. Konshin, and M. M. Rusanov, has been awarded the prize for the development and production of super-wide-angle multiplexes.

The super-wide-angle multiplex is intended for stereophotogrammetric processing of photographs taken with super-wide-angle aerial cameras with a field of view of 122°, used for mapping.

The introduction of these instruments into aerial-survey production made it possible to abandon the formerly widespread, expensive, and low-productivity differentiated method, which did not provide the required accuracy, especially in processing mountainous regions.

Super-wide-angle multiplexes are also suitable for processing photographs obtained with any other, less wide-angle cameras (for example, cameras with a field of view of 70–96°) and eliminate the need for multiplexes specially designed for this purpose.

Super-wide-angle multiplexes provide more perfect orthoscopy than all previously existing multiplexes, owing to a more perfect calculation of the optics and more advanced methods of aligning and checking the optics.

B. P. Kozyrev, associate professor at the Leningrad Electrotechnical Institute named after V. I. Ulyanov (Lenin), has been awarded the prize for the creation of photoelectro-optical amplifiers (FEOU-9 and FEOU-10).

The photoelectro-optical method developed by B. P. Kozyrev is based on a combination of a galvanometer and photocells and does not require the use of cathode lamps.

Interference caused by ground vibration has been eliminated by the author through the introduction of a sharply over-damped regime in the input galvanometer. As a result of applying this principle, using a two-beam optical channel, and creating new types of galvanometers, B. P. Kozyrev succeeded in attaining a measurement accuracy down to \(10^{-9}\) volt, which makes it possible successfully to solve the problem of absolute measurements of radiation by thermal methods.

Corresponding Member of the Academy of Sciences of the Ukrainian SSR I. N. Frantsevich and his coworkers A. A. Abinder and S. V. Borisov have been awarded the prize for the development and mastery of the production of contact alloys.

Corresponding Member of the Academy of Sciences of the USSR A. V. Shubnikov has been awarded the Stalin Prize as the leader of the work on creating apparatus and technology for the production of synthetic rubies.

V. V. Shepel.