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1.
The concept of propagation in time of Vigier and co-workers (V et al.) implies the idea of a supertime; it is thus alien to most Minkowskian pictures and certainly to mine. From this stems much of Vet al.'s misunderstandings of my position. In steady motion of a classical fluid nobody thinks that momentum conservation is violated, or that momentum is shot upstream without cause because of the suction from the sinks! Similarly with momentum-energy in space-time and the acceptance of an advanced causality. As for the CT invariance of the Feynman propagator, the causality asymmetry it entails is factlike, not lawlike. The geometrical counterpart of the symmetry between prediction and retrodiction and between retarded and advanced waves, as expressed in the alternative expressions B|UA=BU|A=B|U|A for a transition amplitude between a preparation |A and a measurement |B, is CPT-invariant, not PT-invariant. These three expressions respectively illustrate the collapse, the retrocollapse, and the symmetric collapse-and-retrocollapse concepts. As for Sutherland's argument, what it falsifies is not my retrocausation concept but the hidden-variables assumption he has unwittingly made.  相似文献   

2.
We establish a new three-mode entangled state representation , of continuum variables, which make up a complete set. Using optical four-wave mixing and a beam splitter transform we can prepare , . Based on , a new number-difference--operational-phase uncertainty relation is established and the corresponding squeezing dynamics is discussed.  相似文献   

3.
Analyses of mean site content, mean bond content, mean perimeter and related quantities give a susceptibility diverging as (p c –p), with 2.41±0.025. This exponent disagrees with some earlier estimates but it is consistent with the (p c –p)–2.388... divergence predicted by the formulas of den Nijs, Nienhuis et al. and Pearson.  相似文献   

4.
We propose a Veneziano-like model for VV reactions near threshold involving exchanges of 0 trajectories int- andu-channels. The model is applied to , , , and processes. The model in its simplest form cannot account for the disparities in the cross sections for andK *+ K *– and for 00 and +. Further refinements of the model are suggested.  相似文献   

5.
We compute by direct Monte Carlo simulation the main critical exponents, , 4, andv and the effective coordination number for the self-avoiding random walk in three dimensions on a cubic lattice. We find both hyperscaling relationsdv=2– anddv– 2 4+=0 satisfied ind = 3.  相似文献   

6.
In this paper we give a characterization of the modular group of a von Neumann algebra , with a cyclic and separating vector, which provides at the same time a necessary and sufficient condition so that two von Neumann algebras 1 and 2, such that 12, are the mutual commutants, i.e. 1=2.An application is made to the duality property in Quantum Field Theory, and we give a sufficient condition for PCT invariance in a theory of local observables.Partially supported by C.N.R.  相似文献   

7.
We investigate the time evolution of a model system of interacting particles moving in a d-dimensional torus. The microscopic dynamics is first order in time with velocities set equal to the negative gradient of a potential energy term plus independent Brownian motions: is the sum of pair potentials, V(r)+ d J(r); the second term has the form of a Kac potential with inverse range . Using diffusive hydrodynamic scaling (spatial scale –1, temporal scale –2) we obtain, in the limit 0, a diffusive-type integrodifferential equation describing the time evolution of the macroscopic density profile.  相似文献   

8.
Contrary to what would be predicted on the basis of Cramérs model concerning the distribution of prime numbers, we develop evidence that the distribution of (x+H)–(x), for 0xN, is approximately normal with mean H and variance HlogN/H, when NHN1–.Dedicated to Freeman Dyson, with best wishes on the occasion of his eightieth birthdayResearch supported by NSF grants DMS–0070720 and DMS–0244660.Research supported by the American Institute of Mathematics and NSF grants.  相似文献   

9.
The neutron density in the vicinity of a black cylindrical rod partly inserted in a bare reactor is calculated and illustrated by a numerical example. The starting point is a two-group diffusion theory approximation. While the dependence of the effect of the rod on the insertion depth can be calculated simply by means of perturbation theory, the question of the neutron density estimate in the vicinity of the rod is considerably more difficult and in some considerations the estimate of the neutron density caused by the presence of the rod is indispensable. The method makes it possible to determine the reactivity value of the rod in dependence on the insertion depth and especially the neutron density deformation in the vicinity of the rod.
()
. , . , , . , . [1] . .


In conclusion the author thanks J. Svato for help in carrying out the numerical calculations.  相似文献   

10.
The change in integrated intensity of the (200) reflections of a solid solution during the formation of G.P. zones was measured and compared with the change in the character of the diffuse streaks corresponding to them. It was found that the. formation of G.P. zones does not lead to a decrease in primary extinction despite the great changes in the distribution of the copper atoms. It was shown that the formation of a precipitate accompanied by the formation of crystallographically incoherent boundaries greatly decreases the primary extinction.
. II. 1-u 4%: [. . ]
(200) . . , . , . . , . , , , .
  相似文献   

11.
In a systematic study of the transfer process to sulphur dioxide, in seven different H2 + SO2 gas mixtures, the time spectra of the muonic sulphur X-rays yield muon transfer rates to the SO2 molecule, deduced from the lifetimes of the p atoms, which agree all well with each other. The muonic oxygen time spectra show an additional structure as if p atoms of another kind were present. Reduced transfer ratesO are reproducible if one uses the model of ephemeral p atoms. The intensity ratios between the different kinds of p atoms are also discussed in the framework of this model and the one of black and white p atoms.  相似文献   

12.
We obtain non-tangential boundary estimates for the Dirichlet eigenfunctions n and their gradients {n } for a class of planar domains with fractal boundaries. This class includes the quasidiscs and, in particular, snowflake-type domains. When applied to the case when is the Koch snowflake domain, one of our main results states that {1()} tends to or 0 as approaches certain types of boundary points (where 1 > 0 denotes the ground state eigenfunction of the Dirichlet Laplacian on ). More precisely, let Ob (resp., Ac) denote the set of boundary points which are vertices of obtuse (resp., acute) angles in an inner polygonal approximation of the snowflake curve . Then given Ob (resp., Ac), we show that {1()} (resp., 0) as tends to in within a cone based at . Moreover, we show that blowup of {1} also occurs at all boundary points in a Cantor-type set. These results have physical relevance to the damping of waves by fractal coastlines, as pointed out by Sapovalet al. in their experiments on the Koch drum.Research partially supported by the National Science Foundation under Grant DMS-9207098.  相似文献   

13.
Exact self-consistent solutions of the equations that describe a system of interacting spinor and massless scalar fields with the interaction Lagrangian Lint=,,(S), where (S) is an arbitrary function of the invariant S=, are obtained in Bianci I space. The possibility of excluding the initial singularity is studied for the case of a power-law function (S), and isotropic expansion of the space as t is established.Russian University of International Amity. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 7, pp. 53–58, July, 1995.  相似文献   

14.
The field and thickness dependence of the conductivity, charge state, and electroluminescence of Si-SiO2 structures is investigated with the aim of studying the energy-dissipation mechanisms of electrons heated by an electric field in SiO2 films. It is shown that, as well as the previously known dissipation channels (interaction with the phonon subsystem and impact ionization in the SiO2 volume, with characterisic energy losses 1<0.153 eV and 2>9 eV, respectively), account must also be taken of processes of defect excitation at the Si-SiO2 boundary, which are accompanied by radiative relaxation in the electroluminescence bands and characterized by intermediate energy-loss values (1<<2).Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 1, pp. 36–40, January, 1991.  相似文献   

15.
The usual way of obtaining rate equations (RE) and a single equation for the field amplitude (EFA) from the semiclassical laser equations (Lorenz-Haken model) is reexamined by undertaking a systematic elimination procedure developed in synergetics. The RE and EFA are justified in the case 1 (, ) and case 2 (, ), respectively. We show that, because the eliminated variable happens to contain a considerable contribution from an unstable mode, the usual elimination technique in the case 3 (, ) leads to an inconsistency. As important by-products we obtain the RE and EFA for arbitrary cavity relaxation constant (). Some remarks are given on the direct elimination technique in the non-diagonal representation in the study of instabilities.  相似文献   

16.
The ac resistivity of a 110 K phase multiphase polycrystalline Ca-Sr-Bi-Cu-O compound and an 85 K phase single-crystalline Ca0.9Sr2.1Cu2.0O8 + has been measured in various magnetic fields up to 8 T. Values forB c 2/ (0) of 71.5 T and forB c2 (0) of 542 T are found for the 85 K phase sample. A value forB c2(0) of 57.9 T is estimated for the 110K phase compound.  相似文献   

17.
Zusammenfassung Aus den Projektionen der Elektronendichten in drei voneinander unabhÄngigen kristallographischen Ebenen wird die Funktion (2) zusammengesetzt, die das übliche Darstellungsverfahren mit Hilfe der dreidimensionalen Fourierreihe ersetzt.
(2), .
  相似文献   

18.
Let : [0, 1][0, 1] be a piecewise monotonie expanding map. Then admits an absolutely continuous invariant measure. A result of Kosyakin and Sandler shows that can be approximated by a sequence of absolutely continuous measures n invariant under piecewise linear Markov maps itn. Each itn is constructed on the inverse images of the turning points of . The easily computable measures n are used to estimate the Liapunov exponent of . The idea of using Markov maps for estimating the Liapunov exponent is applied to both expanding and nonexpanding maps.  相似文献   

19.
Using cosmological relativity theory, we derive the formula for the cosmological redshift written explicitly in terms of 1 – , where = /c is the ratio of the average mass density to the critical closure density. Based on the present day data of observed redshifts, we conclude that < 1, which means the universe is infinite and curved, and expands forever.  相似文献   

20.
The paper solves the problem of gas ionization in a discharge path in a very dilute gas, where the free path of the electrons is much larger than the dimensions of the path and the transit time of the electrons between the electrodes is of the order of the period of the applied h-f voltage. It was found that for a certain ratio of the transit time of the electrons between the electrodes in the discharge path to the period of the h-f oscillation, resonance occurs when the wattless current component is zero. The electron density rises in the path and thus also the gas ionization.
, , , . , , . , .


In conclusion, the author would like to thank F. Benda for preparing the equipment, M. Kivánek for preparing the equipment and some of the measurements, and A. Hrdá for the measurements and for working out the case with equally large a-c and d-c voltages within the framework of her thesis.  相似文献   

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