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1.
We investigate the Finkelstein-Misner geons for a non-simply-connected space-time manifold (M, g 0). We use relations between different Lorentzian structures unequivalent tog 0 and topological properties ofM given by the Morse theory. It implies that to some pieces of geons we have to associate Wheeler's worm-holes. Geons that correspond to time-orientable Lorentz structures are related tog 0 by Morse functions that describe the attaching of a handle of index one. In the case of geons associated to time-nonorientable Lorentzian structures, appropriate handles are related to loops along which the notion of time reverses. If we assume electromagnetic properties of geons, then only four species, v, e, p, m, of different geons can exist and geon m has to decay according to mv+p+e.  相似文献   

2.
It is shown that the foliation of a space-time manifold of codimension 2 provides a basis for the study of the deformation of magnetic field lines. It is found that the fluid flow vector and the curvature vector of a nongeodesic stiff magnetic field line are always orthogonal. Further, it is shown that the metric tensor of the 2-space orthogonal to the Maxwellian string is Lie-transported along the magnetic field lines when the magnetic field lines are stiff. If there exists a spacelike Killing vector field parallel to the magnetic field, then the magnetic field lines must be stiff.  相似文献   

3.
The Dirac spinors and matrices are used in combination with the Arnowitt-Deser-Misner formalism in order to obtain yet another formulation of Hamiltonian general relativity, together with a new form of the Gauss-Codazzi equations. The relation with Ashtekar's variables is analyzed; it is shown, for instance, that the matrices are equivalent to the electric field variable. The electric and magnetic decomposition of the gravitational field is also studie using Dirac matrices.  相似文献   

4.
The major reasons for the low photovoltaic efficiency of Cu2S/CdS cells, in which the CdS film is deposited by spraying, are due to small film thicknesses which do not exceed 4 m and the small average grain size which ranges from 0.1 to 0.5 m.A new experimental solution spraying procedure is described that prevents both restrictions by controlling the substrate temperature. Average grain sizes of more than 1 m are obtained.Work supported by Ministere Pubblica Istruzione and Centro Regionale Ricerche Nucleari e di Struttura della Materia  相似文献   

5.
Anti-photon     
It should be apparent from the title of this article that the author does not like the use of the word photon, which dates from 1926. In his view, there is no such thing as a photon. Only a comedy of errors and historical accidents led to its popularity among physicists and optical scientists. I admit that the word is short and convenient. Its use is also habit forming. Similarly, one might find it convenient to speak of the aether or vacuum to stand for empty space, even if no such thing existed. There are very good substitute words for photon, (e.g., radiation or light), and for photonics (e.g., optics or quantum optics). Similar objections are possible to use of the word phonon, which dates from 1932. Objects like electrons, neutrinos of finite rest mass, or helium atoms can, under suitable conditions, be considered to be particles, since their theories then have viable non-relativistic and non-quantum limits. This paper outlines the main features of the quantum theory of radiation and indicates how they can be used to treat problems in quantum optics.It is a pleasure to join in the 60th birthday celebration of the Director, Herbert Walther, of the Max-Planck-Institute for Quantum Optics at Garching, and wish him much happiness and many more years of his very great scientific creativity.  相似文献   

6.
Two methods axe considered to tap the earths' rotational energy. This ancient collapsed gravitational energy exceeds the earth-lunar binding energy. One involves an orbiting electromagnetic-gravitational coupling system whereby the earth's rotation, with its nonuniform mass distribution, first uses gravity to add orbital energy to a satellite, similar to a planetary flyby.rd The second stage involves enhanced satellite drag as current-carrying coils withdraw the added orbital energy as they pass through the earth's nonuniform magnetic field. A second more direct method couples the earth's rotational motion using conducting wires moving through the noncorotating part (ionospheric current systems) of the geomagnetic field. These methods, although not immediately feasible, are considerably more efficient than using pure gravitational coupling to earth-moon tides.  相似文献   

7.
A misunderstanding persists between Stuart and me, which I do my best to clarify. Bayesian inverse subjectivities versus relativistic covariance and physical intersubjectivity are discussed. A joint number of chances formalism taking care of the propagation of the probability of causes is proposed.  相似文献   

8.
We define two new models on the square lattice in which each allowed configuration is a superposition of a covering by white dimers and one by black dimers. Each model maps to a solid-on-solid (SOS) model in which the height field is two dimensional. Measuring the stiffness of the SOS fluctuations in the rough phase provides critical exponents of the dimer models. Using this height representation, we have performed Monte Carlo simulations. They confirm that each dimer model has critical correlations and belongs to a new universality class. In the dimer-loop model (which maps to a loop model) one height component is smooth, but has unusual correlated fluctuations; the other height component is rough. In the noncrossing-dimer model the heights are rough, having two different elastic constants; an unusual form of its elastic theory implies anisotropic critical correlations.  相似文献   

9.
Zusammenfassung Es werden zwei Begriffe: Homogenität des Raumzeitkontinuums und Kovarianz der Gleichungen, wie sie in der Relativitätstheorie gebraucht werden, definiert und erläutert. Es wird gezeigt, doss die beiden Begriffe wesentlich verschieden sind und in Form nichtäquivalenter mathematischer Bedingungen ihren Ausdruck finden. Trotzdem werden beide Begriffe sowohl von Einstein, als auch in der Literatur über Relativitätstheorie mit einem und demselben Wort Relativität bezeichnet. Der Missgebrauch des Wortes Relativität bedeutet nicht nur einen terminologischen Fehler, sondern spricht auch von einem ungenügenden Verständnis der Grundidee der Relativitätstheorie, besonders der sog. allgemeinen Relativitätstheorie. Versteht man unter Relativität Homogenität des Raumes, so ist in der sog. allgemeinen Relativitätstheorie überhaupt keine Relativität vorhanden. Versteht man dagegen unter Relativität Kovarianz der Gleichungen, so steckt in jener Theorie nicht mehr Relativität, wie z. B. in den unrelativistischen Bewegungsgleichungen, welche ebensogut eine allgemein-kovariante Formulierung gestatten (Lagrangesche Gleichungen 2-ter Art). Die Bezeichnung allgemeine Relativitätstheorie ist daher irrefuhrend. Die geniale Theorie Einsteins ist eine reine Gravitationstheorie. , No 4, . 131, 1955. (RhilosophischeFragen No 4, S. 131, Moskau 1955. Ins Deutsche über setzt vom Verfasser).  相似文献   

10.
Scalar scattering of light on the 3p and 3s subshells of the argon atom (Stokes scattering) and anti-Stokes scattering on the excited 4p and 4s states of argon are examined in the Hartree-Fock approximation. The calculation is made in a velocity form and in a length form. It is shown that the value in the r form is 1.5–2 times greater than in the form.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 1, pp. 36–42, January, 1977.  相似文献   

11.
Recent AGS experiments contributing to our knowledge of hypernuclei are reviewed. These experiments have suggested new areas of research on hypernuclei. With the proper beam line facilities, the AGS will be able to perform experiments in these areas and provide a transition to the future era of kaon factories.Invited contribution to the symposium Mesons and Light Nuclei, Bechyn, Czechoslovakia, May 27–June 1, 1985.  相似文献   

12.
Bohr's 1930 derivation of the uncertainty relation c 2 m th bears a close relationship to Einstein's 1913 derivation of the gravitational redshift via the equivalence principle. A rewording of Bohr's argument is presented here, not taking the last step of acceleration as equivalent to a uniform gravity field, thus yielding a derivation of the formula c 2 m th, avoiding Treder's 1971 objection.  相似文献   

13.
A comparison was made of island deposits of gold on NaCl, produced by thermal vaporization (thermal Au/NaClid) and cathode sputtering (cathode Au/NaClid). In thermal Au/NaClid, two orientations of the gold microcrystals with respect to the NaCl (100) shear face were observed; multiply twinned particles were formed. In cathode Au/NaClid, only one orientation is present and the formation of complex particles is not observed.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii Fizika, No. 11, pp. 46–50, November, 1971.  相似文献   

14.
This paper proves rigorously that the structure factor of the structure intermediate between quasiperiodic and random introduced by Aubry. Godréche, and Luck is purely singluar continuous apart from a delta function at zero for most choices of the parameters. The result is based on a proof that a flow under a steep function over an irrational circle rotation is weakly mixing for most parameters, and on the wonderland Theorem.  相似文献   

15.
A quasi-linear regression formula is derived by an expansion around quasi-static equilibrium. It relates the relaxation of thermodynamic forces to the regression of correlations of thermodynamic coordinates in quasi-static equilibrium. Correlation functions and memory kernels can be introduced in almost complete analogy to linear response theory. A non-linear, non-Markovian kinetic equation is derived. The kinetic coefficients are given in terms of correlation functions of stochastic forces in quasi-static equilibrium similar to the linear theory.  相似文献   

16.
Understanding quantum theory as a general theory of prediction, we reconstruct abstract quantum theory. Abstract means the general frame of quantum theory, without reference to a three-dimensional position space, to concepts like particle or field, or to special laws of dynamics. Reconstruction is the attempt to do this by formulating simple and plausible postulates on prediction in order to derive the basic concepts of quantum theory from them. Thereby no law of classical physics is presupposed which would then have to be quantized. We briefly discuss the relationship of theory and interpretation in physics and the fundamental role of time as a basic concept for physics. Then a number ofassertions are given, formulated as succinctly as possible in order to make them easily quotable and comparable. The assertions are arranged in four groups: heuristic principles, verbal definitions of some terms, three basic postulates, and consequences. The three postulates of separable alternatives, indeterminism, and kinematics are the central points of this work. These brief assertions are commented upon, and their relationship with the interpretation of quantum theory is discussed. Also given are an outlook on the further development into concrete quantum theory and some philosophical reflections.  相似文献   

17.
The two main arguments concern(1) the presence of an enlightened complementarity between philosophic (including scientific) and religious (not including mystic) thought, and(2) the necessity to postulate a threefold relationship whenever one is to gain knowledge of any kind. They are both inspired by physics (from Bohr's strict complementarity, resp. from Newton's fundamental postulate).God's perfection resides at least in Symmetry in a generalized (not restrictively spatial) sense. Yet, as the argument goes, Space does not exist as a thing. Consequently, the Great Geometer (God) cannot dwell within a World He creates, and it is wrong to speak about His (God's) existence; for, existence is bound to the temporal, and Time is, together with the World, part of God's creation. Thus the only possible creation consists in God separating World and Time from Himself: This is the paradigm of Symmetry-breaking.Polytheistic mythologies all assume such and such imperfection of their deities; hence perfection is meaningful for monotheism only. A relationship of a threefold (trinitary) nature must then obtain between God, World, and Time; this is analogous to Newton's postulate relating force, momentum and time. Just as the latter and its specific generalizations must be found true by verification, the said threefold relationship must also be found true: within philosophic thoughtmore geometrico (in a generalized sense), within religious thoughtmore hymnometrico. Yet the complementarity (called enlightened) arising between the two kinds of thought is of a higher nature than Bohr's strict complementarity. While it can be understood from the role assumed by language itself, it can however only be disposed of within mystic contemplation.Dedicated to Sir KARL POPPER on the occasion of his 90th birthday.  相似文献   

18.
Quite often the compatibility of the EPR correlations with the relativity theory has been questioned; it has been stated that the first in time of two correlated measurements instantaneously collapses the other subsystem; it has been suggested that a causal asymmetry is built into the Feynman propagator. However, the EPR transition amplitude, as derived from the S matrix, is Lorentz andCPT invariant; the correlation formula is symmetric in the two measurements irrespective of their time ordering, so that the link of the correlations is the Feynman zigzag, and that causality isCPT invariant at the microlevel; finally, although the Feynman propagator has theP andCT symmetries, no causal asymmetry follows from that. As for Stapp's views concerning process and becoming, and his Whiteheadean concept of an advancing front, I object that they belong to factlike macrophysics, and are refuted at the microlevel by the EPR phenomenology, which displays direct Fokker-like space-time connections. The reason for this is a radical one. The very blending of a space-time picture and of a probability calculus is a paradox. The only adequate paradigm is one denying objectivity to space-time—but this, of course, is also required by the complementary of the x and the k pictures, which only look compatible at the macrolevel. Therefore, the classical objectivity must yield in favor of intersubjectivity. Only the macroscopic preparing and measuring devices have factlike objectivity; the transition of the quantal system takes place beyond both thex and thek 4-spaces. Then, the intrinsic symmetries between retarded and advanced waves, and statistical prediction and retrodiction, entails that the future has no less (but no more) existence than the past. It is the future that is significant in creative process, the elementary forms of which should be termed precognition or psychokinesis—respectively symmetric to the factlike taboos that we can neither know into the future nor act into the past. It is gratifying that Robert Jahn, at the Engineering School of Princeton University, is conducting (after others) conclusive experiments demonstrating low level psychokinesis—a phenomenon implied by the very symmetry of the negentropy-information transition. So, what pierces the veil of maya is the (rare) occurrence of paranormal phenomena. The essential severance between act and potentia is not a spacelike advancing front, but the out of and the into factlike space-time. Finally, I do not feel that an adequate understanding of the EPR phenomenology requires going beyond the present status of relativistic quantum mechanics. Rather, I believe that the potentialities of this formalism have not yet been fully exploited.  相似文献   

19.
We propose a scheme for building a free-electron laser in the soft X-ray region pumped by the soliton laser. Making use of soliton laser wave evolution shape and single-pass small signal analysis, we find that this laser has two special advantages over the previous electromagnetic wave undulator free-electron lasers. One is a very small mass-shift effect because of the special characteristics of soliton laser; the other is that it has an additional frequency tuning effect based on the conventional free-electron laser's tunability. We also obtain the small signal gain and present some discussion.  相似文献   

20.
In their paper A note on Misunderstandings of Piron's Axioms for Quantum Mechanics, Foulis and Randall undertake a reply to our critique of Piron's question-proposition system (qp-s) which appeared in previous issues of this journal. In the present paper, we want briefly to refute the points of criticism raised by Foulis and Randall (FR). We argue that the misunderstandings are not ours, and we prove it.  相似文献   

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