Acta Physica Polonica (1932 – 1969)



show all volumes


Vol. XV (1956)

Fasc. 1, pages 3–75

J. Dąbrowski, J. Sawicki
Angular Distribution of Deuterons from \(^9\)Be(p,d)\(^8\)Be. II. (Supplement)
Acta Phys. Pol. 15, 3 (1956)

abstract Having finished the present paper we have learned of the recent results of J.B. Reynolds and K.G. Stauding concerning the \(^9\)Be(p,d)\(^8\)Be reaction for 16.5 Mev protons. We give here the comparison of these results with our theory for \(r_0=5 \times 10^{-13}\) cm. The angular distribution is given in Fig. 5. The absolute values of the cross-section are given in Table II. The agreement of the Born approximation theoretical angular distribution with the experimental points is quite satisfactory save for the point \({\mit \Theta }_s\sim 8^\circ \). The Butler distribution is in contradiction to experiment. However the discrepancy between the Born approximation theoretical and the experimental absolute values of the cross-section seems to be rather great. It seems hard to be explained by the neglect of the proton — \(^8\)Be interaction only.

D. Stachórska
Temperature Changes and Condensation During Adiabatic Expansions of Air Saturated with Vapour
Acta Phys. Pol. 15, 5 (1956)

abstract If a dry gas of temperature \(T_1\) expands adiabatically its temperature falls, reaching a certain value \(T_2\). This value may be calculated with the help of well-known equations, provided that the ratio of initial and final volumes is known. If before expanding the gas contained saturated vapour at \(T_1\), condensation may occur during the expansion, and owing to the condensation heat we finally obtain a temperature \(T\), which is higher than \(T_2\). The aim of this work was to measure temperature changes occurring during expansion in a Wilson chamber. For this purpose a resistance thermometer was used made of wire of about 10 \(\mu \) diameter. This thermometer was mounted in a Wheatstone bridge system in which a cathode ray oscilloscope served as an indicator. Measurements were performed either in the presence of a powerful ionizing substance, or without this substance, but in the presence of a field which removed the ions. In both cases diagrams of the dependence of the temperature decrease \(\Delta T \) on the ratio of final and initial volumes \(v_2/v_1 \) were obtained. The limit of condensation is indicated in these curves by an abrupt change of the slope. When the ratio \(v_2/v_1 \) crosses the critical expansion ratio (the limit of condensation) the character of the oscillogram is radically changed. There appears a steep section corresponding to the emitted heat of condensation. The final point of this section determines the equilibrium temperature \( T \). This experimental value is in good agreement with that calculated on theoretical basis. If we take the existence of this steep section in the oscillogram as a criterion of condensation, then from the measured values we may calculate the limit of condensation on ions and on neutral aggregates. The values obtained in this way for alcohol vapour, namely 1.150 and 1.180, are in agreement with those found by other authors by means of direct observation of appearing drops. From the inclination of the mentioned section the time of the condensation could be estimated. For the expansion \(v_2/v_1=1.170 \) in the presence of an ionizing sample it is of the order of 0.02·sec.

R. Gajewski
On Transient Radiation of a Dipole Inside a Wave Guide. I
Acta Phys. Pol. 15, 25 (1956)

abstract Exact formulae are given for an electromagnetic field radiated by a dipole situated inside a wave guide of an arbitrary cross section, the moment of the dipole depending on time through a factor \(1(t)(1-{\rm e}^{-\varrho t})\sin \omega _0t\), where \(1(t)\) is Heaviside’s step function.

B. Adamczyk, W. Staszewski
On the Longitudinal Attraction and Repulsion of Spheres in Vibrating Air
Acta Phys. Pol. 15, 43 (1956)

abstract The force acting on spheres in a Kundt tube with their line of centres parallel to the tube axis has been investigated. As in the previous paper on the mutual influence of spheres in the transverse position it is shown that for the longitudinal position this force depends on the frequency and intensity of the air vibrations as well as on the size of the spheres. The force at very small distances is shown in some cases to be one of repulsion, so that Andrade’s results cannot he generally true.

Z. Galasiewicz
Generalization of the Method of Supplementary Variables to Systems Composed of Two Kinds of Particles
Acta Phys. Pol. 15, 49 (1956)

see erratum: Acta Physica Polonica 15, 358 (1956)

abstract It is shown that the elementary excitations in a system composed of electrons and ions (interacting electrostatically) are of two types: a boson type and a fermion one. The boson type excitation may be described as a system of oscillators vibrating with the frequency \(\sqrt {\omega ^2_1+\omega ^2_2}\), where \(\omega _1\) is the Langmuir frequency of the electron vibrations (vibrations of the electron plasma) and \(\omega _2\) is the Langmuir frequency of the ion vibrations (vibrations of the ion plasma). If one neglects the (Coulomb) interaction between the ions and electrons, the elementary boson-type excitations are given by two systems of oscillators vibrating with the frequencies \(\omega _1\) and \(\omega _2\). As \(\sqrt {\omega ^2_1+\omega ^2_2}\lt \omega _1 + \omega _2 \), the energy of the zero-point oscillations in the case of non-negligible interaction between the ions and electrons is smaller than when this interaction is absent. The energy difference of both these zero-point oscillations may be considered as a measure of the binding energy of the system coming from the “long-range” Coulomb interaction (which is responsible for the boson-type excitations). This energy has been evaluated for Li, Na, and K and compared with the total binding energy calculated by other methods or found experimentally. The orders of magnitude are the same and the results of the author lie nearer to the experimental values as those following from the Hartree–Fock method.

S. Michalak, A. Zawadzki
La Charge de l’Impulsion en Fonction de la Surtension dans un Compteur G.M. a Cathode Metallique et en Verre
Acta Phys. Pol. 15, 63 (1956)

abstract La valeur de la charge d’une impulsion dans un compteur G.M. d’un type quelconque est d’après la théorie de Wilkinson une fonction de la surtension qui s’exprime approximativement par une droite qui change son inclinaison en on certain point. Les auteurs ont déterminé le coefficient de proportionnalité entre la charge et la surtension et ont étudié sa dépendance des paramètres géométriques du compteur. Ce coefficient \(K = AC\), où \(C\) est la capacité du compteur et \(A\) une constante qui dépend uniquement du diamètre de l’anode. La valeur de ce coefficient est la même pour les compteurs ordinaires (à cathode métallique) et pour les compteurs de type Maze (à cathode en verre). La connaissance de la valeur de \(A\) est utile dans l’étude pratique d’un compteur G.M. et surtout d’un compteur à cathode en verre.

J. Sawicki
Note on the \(^6\)Li(\(d,\alpha \)) \(^4\)He Reaction
Acta Phys. Pol. 15, 71 (1956)

abstract Resnick and Inglis (1949) have given the compound nucleus theory for the \(^6\)Li(\(d,\alpha )^4\)He reaction and have compared their results with existing experiments up to energy 3.75 Mev. In this energy range satisfactory agreement with experiment was obtained for the angular distribution. However, for much higher energies the pick-up process of the odd proton and neutron loosely bound with the \(\alpha \)-core in the \(^6\)Li nucleus by the incident deuteron seems to be most important.

A. Feltynowski, I. Glass
Coal Surface Analysis by Means of an Electron Microscope
Acta Phys. Pol. 15, 75 (1956)

abstract It is the purpose of this paper to elaborate a method for the examination of pitcoal surface by means of an electron microscope. Coal surface has been examined in an electron microscope already in 1943 by Preston and Cuckow, yet even now the obtaining of exact replicas is still a difficult problem. In our investigations we used chromium shadowed aluminium replicas and it seems that we have obtained better results than previous authors, which have been using negative formvar replicas and positive polystyrene replicas.

Fasc. 2, pages 79–146

Z. Galasiewicz
On the Equivalence of the Zubarev Method and the Bohm–Pines Method for Systems of Two Types of Particles
Acta Phys. Pol. 15, 79 (1956)

abstract In this work, the method presented by Bohm and Pines (Phys. Rev., 92, 609 (1953)) for the collective description of systems of two types of particles (electrons and ions) has been generalized. The result is compared with the results previously obtained by the author (Galasiewicz, Acta Phys. Polon., 15, 49 (1956)) for the generalization of the Zubarev method of supplementary variables (J. Phys. USSR, 25, 548 (1953)) for the same case. The equivalence of both methods is shown. The unitary transformation which transforms the Hamiltonian obtained by one method into the Hamiltonian obtained by the other is given.

J. Rayski
A Discussion on Bilocality
Acta Phys. Pol. 15, 89 (1956)

abstract The conceptual situation in contemporary theoretical physics is discussed. The position and displacement operators \(x_\mu \), \(d_\mu \) form an abstract algebra constituting a natural generalization of the concept of space-time (space-time quantization), and a starting point for a bilocal theory. The canonical transformations of the operators \(x_\mu \), \(d_\mu \) have to play an important role. The linear subgroup of the group of canonical transformations is unimodular. This offers a simple and natural interpretation of isospin. The problem of rest-mass is also discussed. Mass consists of two parts: a kinetic (mechanical) mass and a field mass. The former is connected with the internal motion of the bipoint particle. For higher states of internal motion the self-mass is probably negligible in comparison with the kinetic mass.

M. Suffczyński
Two-center Integrals for Body-centered Iron Using Atomic Functions with Exchange
Acta Phys. Pol. 15, 111 (1956)

abstract Two-center integrals for metallic body-centered iron have been calculated using the new atomic wave functions calculated with exchange by J.H. Wood. The integrals turn out to be about two times smaller than those based on the wave functions without exchange.

W. Hanus, J. Rayski
On the Mass Spectra for Bosons
Acta Phys. Pol. 15, 117 (1956)

abstract Two different mass operators consistent with the bilocal theory are constructed for bosons. One of them seems to apply to the pion family, the other (constructed with the aid of Duffin–Kemnier matrices) seems to apply to the \(K\)-meson family (\({\mit \Theta }^0\)-family).

J. Rayski
A Variational Principle for Bilocal Field Theory
Acta Phys. Pol. 15, 123 (1956)

abstract The generalized Schrödinger–Gordon–Fock equations of the bilocal field theory are derived as the Euler–Lagrange equations of a suitably formulated variational principle.

W. Czyż
A Simple Nuclear Model for \(^7\)Li and Its Use in Investigating the Reaction \(^7\)Li(\(\gamma \),\(^3\)H)\(^4\)He
Acta Phys. Pol. 15, 129 (1956)

abstract For computing the total and differential cross sections for the reaction \(^7\)Li(\(\gamma \),\(^3\)H)\(^4\)He, a ‘two-body’ nuclear model was used for \(^7\)Li. It has been assumed for this model that the \(^7\)Li nucleus can be regarded as a compound system composed of a triton and an \(\alpha \) particle rotating around the common centre of mass. The cross section curve so obtained basically agrees with the results obtained experimentally if we assume that the forces due to the interaction of the triton with the \(\alpha \) particle are repulsive in the D state.

L. Jarczyk, Z. Lewandowski
Application of the Herschel Effect for Selective Erasing of Background in Nuclear Emulsion
Acta Phys. Pol. 15, 143 (1956)

abstract Nuclear emulsions are now widely used in nuclear physics. Often there arises the necessity to give the emulsion a heavy exposure to the radiation of a radioactive source or an accelerator. The effect under investigation is then obscured by the background fog produced by \(\gamma \)-rays, creating a serious difficulty in the observation of the proper effect. The aim of the present work was to improve the visibility of nuclear events in photographic emulsions by the selective erasing of the \(\gamma \)-ray background. This note is confined to the method of the Herschel effect only.

J. Wesołowski
An Immersion Beta-Ray G.M. Counter
Acta Phys. Pol. 15, 146 (1956)

abstract In many applications of radioactivity, for example determination of potassium content of solutions, certain processes involving radioactive tracers, etc. thin-walled immersion counters are employed. As metal may be corroded by the solutions used, immersion counters with an exposed metal cathode have obvious disadvantages. Therefore internally coated, thin-walled glass counters are normally employed.

Fasc. 3, pages 151–191

A. Wrzesińska
Impurity-activated Crystalline Phosphors Their Production and Thermoluminescence Curves
Acta Phys. Pol. 15, 151 (1956)

abstract Some useful observations made when searching for methods of making strongly glowing Phosphors (of not very pure materials) are reported. A simple apparatus has been constructed which traces the glow curve directly on the photographic paper by means of a light spot. A uniform increase of temperature is easy to obtain. Some observations concerning the influence of Mg on the depth electron traps have been made. Two new methods of finding the depth of electron traps (without approximate calculations) have been applied to the produced phosphors.

V.L. Ginzburg
On Relativistic Wave Equations with a Mass Spectrum
Acta Phys. Pol. 15, 163 (1956)

abstract The question of relativistic wave equations having a mass spectrum and containing new continuous variables is discussed. Mostly the case for which the new variables are components of some space-like four-vector is considered, since similar equations have been very often used in recent times in connection with attempts to build a non-local field theory.

J. Łopuszański
Some Remarks on the Theory of the Electron–Photon Cascade
Acta Phys. Pol. 15, 177 (1956)

abstract The well known integro-differential equations for the first moments of the distribution for the electron–photon cascade are derived from a integral equation analogous to the Smoluchowski equation from the theory of stochastic processes. Some asymptotic properties of the distribution function are given.

H. Stachowiak
Some Properties of Distribution Functions of Electron–Photon Cascades at Large Absorber Depth
Acta Phys. Pol. 15, 181 (1956)

abstract It is shown that at large depth of absorber, the number of particles found in electron–photon cascades depends only on the spectrum of the primary photons, and that at large depths, the number of particles decreases rapidly as the energy of the particles increases.

H. Konwent, J. Łopuszański
Some Remarks on the Asymptotic Behaviour of the Electron–Photon Cascade for Large Depth of the Absorber
Acta Phys. Pol. 15, 191 (1956)

abstract The present paper is a continuation of the two preceding papers (Łopuszański 1956, Stachowiak 1956, hereafter referred to as papers I and II resp.). We make use of the result obtained there. We also employ the Urbanik’s conclusion (Urbanik 1955) ...

Fasc. 4, pages 207–271

L. Infeld, J. Plebański
Expansion of Singular Functions Associated with the Klein–Gordon Equation
Acta Phys. Pol. 15, 207 (1956)

abstract Two alternative approximation methods involving expansions in powers of \(c^{-1}\) or \(c\) are given for the Klein–Gordon equation. By using these methods, expansions of the more important singular functions such as \(\overline {{\mit \Delta }}\), \({\mit \Delta }\), and \({\mit \Delta }^{(1)}\) are obtained. The connection is shown between this procedure and two alternative methods for formally integrating the Klein–Gordon equation on the basis of analogies with the Yukawa and the harmonic oscillator equations. The main purpose of this paper is to prepare the mathematical basis for the subsequent application of the Einstein–Infeld–Hoffman method to the equations of motion in meson theory.

J. Dąbrowski
Direct Interaction and the Compound Nucleus Formation in Nuclear Reactions
Acta Phys. Pol. 15, 249 (1956)

abstract The formulas for the reaction cross section are derived taking into account both the compound nucleus and the direct interaction mechanisms. The derivation is based on Bethe’s old treatment of nuclear reactions. The final formula for the direct interaction reaction amplitude is obtained in the Born approximation. The compound nucleus reaction amplitude is calculated for one level of the compound nucleus. The cross section is built up with the compound nucleus, the direct interaction and the interference cross sections. The formula is applied to the \((n,d)\) reaction and the results compared with those obtained by Thomas. The treatment of this paper takes into account the transparency of the nucleus.

A. Jabłoński
A Note on the Diffusion Controlled Processes in Luminescent Solutions
Acta Phys. Pol. 15, 263 (1956)

abstract A physical meaning is given to a constant \(\lambda _{ij}\) introduced by the writer in his earlier papers.

J. Stecki
On Surface Tension of Ideal Solutions
Acta Phys. Pol. 15, 267 (1956)

abstract In connection with Puchalik’s work (1954) a letter to the editor was published by Mierzecki (1955) in this journal. An equation was presented, relating the surface tension of the solution to mole fractions of the components. The derivation was based on the assumption that the parachor of the mixture is additive to the parachors of pure components, and that the molar volume of mixing is equal to zero. That equation was suggested for determining the surface tension of an ideal solution, and it was claimed that the logarithmic Szyszkowski’s equation (1908) is not adequate for this purpose.

T. Piwkowski
PbSe and PbTe Infra Red Detectors
Acta Phys. Pol. 15, 271 (1956)

abstract As far as could be ascertained the PbSe photo-conductive and photo-voltaic layers processed by the evaporation method loose their photoelectric properties when exposed to the atmospheric air. The author developed the method, which renders the PbSe layer the property of maintaining its photo-conductive and photo-voltaic sensitivities in the atmospheric air, which is obviously a very valuable characteristic. The PbTe photo-sensitive layers have also been produced by the similar method.

Fasc. 5, pages 275–358

A. Feltynowski, I. Glass, T. Piwkowski, A. Toruń
Microstructure of Photoconductive Lead Sulphide Layers
Acta Phys. Pol. 15, 275 (1956)

abstract The microstructure of PbS layers has been investigated by means of electron diffraction and electron microscopy. The PbS layers were obtained by evaporating in vacuo. The specimens to be examined were prepared by the method of formvar pseudo-replicas or directly by evaporation on thin films of formvar, collodion of aluminium. In general, the PbS layers consist of crystals 200–300 Å in size; an influence of the substratum on the size or shape of these crystals has not been observed. The diffraction patterns of layers deposited directly by evaporation correspond to a regular face-centred lattice of the NaCl type. The diffraction patterns of the pseudo-replicas show characteristic departures from this structure consisting of a decrease in the diameter of the 200 ring and an increase in the diameter of the 220 ring as compared with the diameters of the remaining rings.

A. Kawski
Bemerkungen über die Berechnung des Polarisationsgrades aus der Kompensationseinstellung eines Glasplattensatzes
Acta Phys. Pol. 15, 283 (1956)

abstract Es wurde gezeigt, dass man auf Grund der Neumannschen Formeln für die Intensität des Lichtes nach dem Durchgang durch einen Glasplattensatz (mit Berücksichtigung der mehrfachen Reflexionen an den Plattenoberflächen) eine allgemeine Formel für den Polarisationsgrad in der Kompensationsmethode von Arago angeben kann. Im besonderen erhält man die Formel von Gaviola und Pringsheim, ebenso wie diejenige von Sjewtschenko. Auf Grund der allgemeinen theoretischen Formel für eine beliebige Anzahl von Glasplatten, kann man also den Polarisationsgrad berechnen ohne mit dem Eichen des Satzes zu beginnen.

M. Suffczyński
Two-centre Integrals in Solids
Acta Phys. Pol. 15, 287 (1956)

abstract Fletcher and Wohlfarth’s method of calculating the energy two-center integrals in solids is described in detail.

Z. Galasiewicz
Supplementary Boson-field Method and Collective Oscillations
Acta Phys. Pol. 15, 295 (1956)

abstract In this paper, the method of second quantization is investigated for an ensemble of interacting fermions described by the quantized wave function \(\psi \). The work here is based on the supplementary variables method (D. Zubarev, Candidate’s Degree Dissertation, Moscow University, Moscow, 1953). Bohm and Pines, Phys. Rev., 92, 609 (1953). A supplementary boson field has been introduced into the theory in such a way that the quanta of this field describe the collective motion of an ensemble of fermions (electrons). This is possible, after suitable transformations, since operators connected with the supplementary boson field appear in the Hamiltonian. It is further shown that the transformation of the Hamiltonian can be regarded as a transition to new fermion operators formed from the old fermion operators and from boson operators associated with the supplementary boson field. The method presented here is compared with the method given in the paper of Tomonaga (Progr. Theor. Phys. 5, 544 (1950)).

L. Liszka
A Possible Explanation of the Diurnal Variation in the Intensity of the Night Glow Line (0 I) 5577 Å
Acta Phys. Pol. 15, 305 (1956)

abstract This paper discusses a possible explanation for the diurnal changes in the intensity of the green line of the night glow. These changes may be evoked by periodic changes of pressure in the upper layers of the atmosphere arising from the tidal activity of the sun and the moon. The correctness of the above hypothesis can be confirmed by investigating the relation between the position of the moment of maximum green line intensity and the lunar phase. It can be seen from the curve drawn on the basis of published curves of green line intensity changes available to the author that such a relationship actually exists.

H. Cofta
Halbklassisches Bild der Spinwelle im Ferrimagnetikum
Acta Phys. Pol. 15, 311 (1956)

abstract Im ersten Teil ist eine kurze Begründung des halbklassischen Spinwellenhildes angegeben. Dabei wird eine Differenzengleichung für die lineare Atomkette gebraucht, anstatt der oft benutzten Differentialgleichung für die kontinuierliche Spinverteilung. Im Hauptteil sind die durch Keffer, Kaplan und Yafet auf Grund des halbklassischen Spinwellenbildes für Ferromagnetika und Antiferromagnetika hergeleiteten Dispersionformeln \(\omega (k) \), auf den Fall des Ferrimagnetismus und Antiferrimagnetismus im Sinne von Smart verallgemeinert. In der Smartschen Nomenklatur bedeutet der Ferrimagnetismus gleichgerichtete Nachbarspins, und der Antiferrimagnetismus — entgegengesetzt gerichtete. In beiden Fällen ergibt sich eine gleichartige Abhängigkeit \(\omega (k)\sim k^2 \), die mit dem makroskopischen Verhalten beider Magnetikumstypen übereinstimmt. Die Formel \( \omega (k)\sim k \) für Antiferromagnetismus lässt sich nicht durch gewöhnlichen Grenzübergang \( S_2 \to S_1 \), d. h. durch Betrachtung des Antiferromagnetismus als speziellen Fall des Antiferrimagnetismus, erhalten.

W. Królikowski, J. Rzewuski
Relativistic Two-body Problem in One-time Formulation Separation of Angular Variables in the Case of One-quantum Interaction in Electrodynamics
Acta Phys. Pol. 15, 321 (1956)

abstract The separation of angular variables in the relativistic one-time equation for the two-fermion problem in quantum electrodynamics is carried out for the case of one-quantum interaction. The momentum representation is used. A system of integral equations in one variable is obtained. This system reduces to four equations in the case of \(j=0\), and to eight equations for \(j\not =0\).

J.A. Janik, A. Szkatuła
Two Sided Spark Counter with Large Counting Area for Registering Slow Neutrons
Acta Phys. Pol. 15, 343 (1956)

abstract This paper describes a two-sided spark counter for detecting thermal neutrons. The counter has cathode area of \(7.5 \times 11\) cm\(^2\) and is covered on both sides by a coating of boron. The total length of the 0.08 mm diam. nickeline wires which form the anode of the counter is about 3 mm. From the accompanying characteristics drawn for different concentrations of CO\(_2\) in the air forming the atmosphere of the counter, it can be seen that as the CO\(_2\) concentration increases, the counter efficiency increases, the plateau length decreases and the slope of the characteristic increases. The conditions necessary for the stable operation of the counter are given.

T. Domański
Slow Neutron Detection in Presence of Gamma Radiation
Acta Phys. Pol. 15, 351 (1956)

abstract I present a gamma-insensitive detector of slow neutrons consisting of: scintillator, 931-A type photomultiplier tube, amplifier and discriminator. Although this type of photomultiplier is disadvantageous in scintillation counting it had to be used for reasons of availability.

S.R. Mohanty, T.R. Bhat
Role of Transverse Magnetic Fields in the Electrodeless Gas Discharge and in the Joshi Effect
Acta Phys. Pol. 15, 353 (1956)

abstract The Joshi effect (Joshi 1943, 1945), viz., the instantaneous and reversible photovariation (mainly diminution \(-{\mit \Delta } i\) and, under definite experimental conditions, enhancement \(+ {\mit \Delta } i\)) of the current \(i\) of the gas discharge, is of fundamental importance for theories of the behaviour of electrically excited media and the influence thereon of irradiation. It is observed in numerous gases and vapours, elemental and compound, over a wide range of the operative conditions, e.g., the exciting potential \(V\) (and the attendant electric field \( E \)) (Mohanty, Jayaraman and Krishna Rao 1954), the gas pressure (Mohanty and Kamath 1948), etc ...

ERRATA

Fasc. 6, pages 363–431

S. Bażański
The Equations of Motion of Charged Particles in General Relativity
Acta Phys. Pol. 15, 363 (1956)

abstract Equations of motion of charged particles in general relativity theory are obtained by means of the new method developed by Infeld in 1954. The results differ in details from those published already by Wallace and Bertotti.

A. Piekara, J. Małecki
On a Method of Producing Strong Magnetic Fields of Short Duration
Acta Phys. Pol. 15, 381 (1956)

abstract A method of producing strong magnetic fields of a duration of the order of 50 \(\mu \)sec using a condenser battery of a capacity of 2 \(\mu \)F charged up to 50 kV is described. The problem of making a mechanically resistant coil is discussed. A method of measuring the field intensity with a search coil connected to a cathode ray oscillograph is given. The fields attained intensity up to 350 000 oersteds in a volume of about 1 cc.

F.A.E. Pirani
On the Physical Significance of the Riemann Tensor
Acta Phys. Pol. 15, 389 (1956)

abstract Some of the difficulties of interpretation of general relativity theory can be avoided by employing the tetrad formalism. The timelike vector of any tetrad is identified physically with the velocity vector of an observer, the spacelike vectors with the directions of local Cartesian coordinate axes used by him. It is found that the Newtonian concept of nonrotation is represented most closely if the spacelike vectors undergo Fermi propagation along the observer’s world-line. The behaviour of free particles is investigated by referring to tetrads the equation of geodesic deviation, which provides an immediate physical interpretation for the Riemann tensor. A simple model of a gyroscope is constructed by modifying Papapetrou’s equations of a spinning test particle. The behaviour of this model supports the interpretation of Fermi propagation. The interpretation is developed by investigating the discontinuity in the Riemann tensor across the boundary of a world-tube of matter, using Lichnerowicz’s conditions.

J. Rayski
A Discussion on Bilocality. II
Acta Phys. Pol. 15, 407 (1956)

abstract Two versions of bilocal field theory are discussed, one of them leading to a rotator model of elementary particles in the usual space, the other to a rotator model in the isotopic spin space. It seems that a simultaneous consideration of both generalizations, leading to a classification of particles according to spin and isospin, is most promising. The higher states of mass seem to be connected with rotations in the isospace rather than in the usual space.

Z. Semadeni
Some Remarks on the Bloch’s Theory of Spin-waves
Acta Phys. Pol. 15, 423 (1956)

abstract As one of the greatest successes of his theory of spin-waves Bloch showed (1930) the following dependence of spontaneous magnetization upon temperature \[\overline {M}(T) = \overline {M}(O)\cdot \left [1-\left (\frac {T}{\theta }\right )^{3/2}\right ].\] This was confirmed experimentally. On the basis of the Heisenberg–London model, Bloch treated the interaction of electrons as a perturbation. This leads to a system of linear equations from which an approximate solution is obtained ...

K.F. Wojciechowski
Definition of the Long-range Order Parameters for n-Component Alloys
Acta Phys. Pol. 15, 429 (1956)

abstract In the theory of alloys of two components (Nix et al. 1038) there is defined the long-range order parameter \(s\), which is later connected with the temperature. As a result, the free energy of the alloy can be expressed as a function of only one a supervariable \(s\) (neglecting the dependence on the volume \(v\)).

ERRATA


J. Dąbrowski, J. Sawicki
Angular Distribution of Deuterons from \(^9\)Be(p,d)\(^8\)Be. II
Acta Phys. Pol. 15, 431 (1956)


ver. 2024.11.22 • we use cookies and MathJax