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1.
The structure function S(k; ) for the one-dimensional one-component log–gas is the Fourier transform of the charge–charge, or equivalently the density–density, correlation function. We show that for |k|j in the power series expansion of f(k; ) about k=0 is of the form of a polynomial in /2 of degree j divided by (/2)j. The bulk of the paper is concerned with calculating these polynomials explicitly up to and including those of degree 9. It is remarked that the small k expansion of S(k; ) for the two-dimensional one-component plasma shares some properties in common with those of the one-dimensional one-component log–gas, but these break down at order k8.  相似文献   

2.
Four classes of solutions are found to the equations R=–2; ; and g ;=0 in three-dimensional space with metric gdxdx and signature (+ ––), equivalent to the Einstein equations Rij=0 in a vacuum for the metric . The metric ds2 assumes axial symmetry and symmetry with respect to the reflection .Translated from Izvestiya Uchebnykh Zavedenii, Fizika, No. 9, pp. 43–45, September, 1976.  相似文献   

3.
Results from percolation theory are used to study phase transitions in one-dimensional Ising andq-state Potts models with couplings of the asymptotic formJ x,y const/¦xy¦2. For translation-invariant systems with well-defined lim x x 2 J x =J + (possibly 0 or ) we establish: (1) There is no long-range order at inverse temperatures withJ +1. (2) IfJ +>q, then by sufficiently increasingJ 1 the spontaneous magnetizationM is made positive. (3) In models with 0<J +< the magnetization is discontinuous at the transition point (as originally predicted by Thouless), and obeysM( c )1/( c J +)1/2. (4) For Ising (q=2) models withJ +<, it is noted that the correlation function decays as xy()c()/|xy|2 whenever< c . Points 1–3 are deduced from previous percolation results by utilizing the Fortuin-Kasteleyn representation, which also yields other results of independent interest relating Potts models with different values ofq.  相似文献   

4.
The Faradayan hypothesis of inductive coupling of the electromagnetic and gravitational fields is briefly discussed. An experiment designed to test the hypothesis wherein samples are spun to see if any electrogravitational charge is induced is described. Results of the experiment are reported. They imply the induction of a charge density * for spinning samples that behaves as *=ma, where m is the mass density of an element of matter experiencing an acceleration a, and is the coupling coefficient for the hypothetical electrogravitational induction effect. In this experiment, is found to have the value(9.6±3.3)×10 –13 statcoulombs/dyne. Tests that seem to rule out explanations of the observed charges in terms of conventional charging mechanisms are considered.  相似文献   

5.
For a family of translation-invariant, ferromagnetic, one-component spin systems—which includes Ising and 4 models—we prove that (i) the phase transition is sharp in the sense that at zero magnetic field the high- and low-temperature phases extend up to a common critical point, and (ii) the critical exponent obeys the mean field bound 1/2. The present derivation of these nonperturbative statements is not restricted to regular systems, and is based on a new differential inequality whose Ising model version isMh+M 3+ M 2M/. The significance of the inequality was recognized in a recent work on related problems for percolation models, while the inequality itself is related to previous results, by a number of authors, on ferromagnetic and percolation models.  相似文献   

6.
LetG denote the infinitedimensional Lie algebra given by communtation relations [a m ,a n ] =c a m+n (m, n=0, 1, ...), wherec are structure constants of the arbitrary centerless Lie algebra. The paper is devoted to the construction of a certain class of skewsymmetric irreducible representations (so called F-representations) of the algebraG .  相似文献   

7.
We consider a ferromagnetic Ising spin system isomorphic to a lattice gas with attractive interactions. Using the Fortuin, Kasteleyn and Ginibre (FKG) inequalities we derive bounds on the decay of correlations between two widely separated sets of particles in terms of the decay of the pair correlation. This leads to bounds on the derivatives of various orders of the free energy with respect to the magnetic fieldh, and reciprocal temperature . In particular, if the pair correlation has an upper bound (uniform in the size of the system) which decays exponentially with distance in some neighborhood of (,h) then the thermodynamic free energy density (,h) andall the correlation functions are infinitely differentiable at (,h). We then show that when only pair interactions are present it is sufficient to obtain such a bound only ath=0 (and only in the infinite volume limit) for systems with suitable boundary conditions. This is the case in the two dimensional square lattice with nearest neighbor interactions for 0<0, where 0 –1 is the Onsager temperature at which (,h=0) has a singularity. For >0, (,h)/h is discontinuous ath=0, i.e. 0=c, where c –1 is the temperature below which there is spontaneous magnetization.Research supported by AFOSR Contract # F 44620-71-C-0013.  相似文献   

8.
For 2D percolation we slightly improve a result of Chayes and Chayes to the effect that the critical exponent for the percolation probability isstrictly less than 1. The same argument is applied to prove that ifL():={(x, y):x=r cos, y=r sin for some r0, or} and():=limpp c [log(pp c )]–1 log Pcr {itO is connected to by an occupied path inL()}, then() is strictly decreasing in on [0, 2]. Similarly, limn [–logn]–1 logP cr {itO is connected by an occupied path inL()() to the exterior of [–n, n]×[–n, n] is strictly decreasing in on [0, 2].  相似文献   

9.
A gas of two Boson systems coexisting inR 3, and interacting only mutually, is analyzed. The interaction is quadratic, so that the dynamical problem may be solved completely and exactly.The initial state is taken to be the mutually uncorrelated Gibbs states: (1) (2) = . We find the time evolved state, and its projections onto the separate species and the subvolumes.The principle consequences of this model are discussed. In particular we examine the possible occurrence of harmonic oscillations between the species.On Study Leave at the Department of Physics and Astronomy, The University of Rochester.This research was partially supported by the National Science Foundation under Contract No. 5-28501.  相似文献   

10.
Lucifer yellow and lissamine rhodamine sulfonyl hydrazine were used as the donor and the receptor, respectively, for Förster energy transfer measurements to determine the location of the subunit in the native Na,K-ATPase from pig kidney. It was found that (1) the subunits are located in one functional complex, i.e., the dimer ()2 appears to be the functional complex of Na,K-ATPase, and (2) the subunits in the functional enzyme complex in the membrane are not located next to each other but are rather well separated. The distance between fluorophores covalently attached to the subunits was found to be 5.3 nm.  相似文献   

11.
We study the resonant magnetopolaron effects in parabolic quantum wells in a tilted magnetic field. The renormalization of the first excited level, which is resonant with the ground state level plus one longitudinal-optical phonon is calculated at the resonance using an improved resonance approximation to be E= where is the polaron coupling constant. The exponent and the factor are calculated in dependence on the tilt angle of the magnetic field and the confinement energy.  相似文献   

12.
We consider a quantum mechanical model which displays the behaviour associated with having a resonance or metastable state. The Hamiltonian depends on a parameter . When =0, there is an eigenstate 0; when 0, 0 dissolves into the continuous spectrum, showing approximate exponential decay. We prove this result without using dilatation analyticity. The model describes a two-state atom coupled to the quantized radiation field. The state space of the field is truncated, so that only the vacuum and one-photon states are included.This work was partially supported by NSF Grant DMS-8922941  相似文献   

13.
The very neutron-deficient 117Ba nuclei were produced in 58Ni-induced reactions on a 63Cu target and selected for spectroscopic studies by using BaF+ molecules formed in the ion source of the GSI on-line mass separator. The -decay of 117Ba was investigated by means of the total absorption -ray spectrometer and a telescope for -delayed particle detection. In the analysis combining the -delayed -ray and proton data the energy window available for -delayed proton emission, the branching ratios for proton transitions to the 116Xe levels and the -feeding of the -ray and proton-emitting 117Cs states were determined. The -strength function for 117Ba derived from the measured -feeding distribution revealed the existence of a broad resonance structure at 117Cs excitation energy of about 4-5 MeV. The results of the -delayed proton studies and -strength measurements are confronted with theoretical predictions.  相似文献   

14.
We define a modified free-time evolution for the Dirac equation with long-range potentials (1/|x|), where is the Dirac matrix, and prove a strong asymptotic completeness of the corresponding wave operators. Our methods also work for the magnetic fields ·A(x).  相似文献   

15.
We define the positive resonance points of self-adjoint operators without using the analytical continuation of corresponding resolvents and show that the limiting amplitude principle for the abstract wave equation does not take place in general, if 2 = , where is the disturbing frequency and is the resonance point. The asymptotics of corresponding solutions as t are obtained, which imply the growth of the oscillation amplitude as t , 0<<1, or as ln t, t .  相似文献   

16.
We consider Glauber dynamics on a finite cube in d-dimensional lattice (d2), which is associated with basic Ising model at temperature T=1/1 under a magnetic field h > 0. We prove that if the effective magnetic field is positive, then the relaxation of the Glauber dynamics in the uniform norm is exponentially fast, uniformly over the size of underlying cube. The result covers the case of the free-boundary condition with arbitrarily small positive magnetic field. This paper is a continuation of an attempt initiated earlier by Schonmann and Yoshida to shed more light on the relaxation of the finite-volume Glauber dynamics when the thermodynamic parameter (, h) is so near the phase transition line, (, h); c < &h = 0, that the Dobrushin–Shlosman mixing condition is no longer available.  相似文献   

17.
A scale-invariant nonlinear modification of Maxwellian electrodynamics within general relativity is proposed. The starting point is the Mie model and its scale-invariant generalization in flat space-timeE 4. We prove that all static, spherically symmetrical regular field configurations in this new theory, as well as those in the Mie model, possess negative energy. In search of solitonlike solutions with positive masses, we take into account their proper gravitational fields. We show first that in Riemannian space any gauge-invariant electrodynamic theory does not admit regular solutions. Supposing the gauge invariance to be broken inside the particle, we prove the existence of static particlelike solutions with spherical symmetry and positive energy in the scale-invariant electrodynamics described by a Lagrangian density of the form =-Y(I)R/(2)-W(I)F F u/2+2X(I)R A A , withY, W, andX arbitrary functions of the invariantI=A A . The correspondence with the Maxwellian theory is required.  相似文献   

18.
The neutrinoless double-beta decay (0 decay) to the first excited 0+ collective final state is examined for A = 76, 82, 100 and 136 nuclei by assuming light Majorana neutrino exchange mechanism. Realistic calculations of nuclear matrix elements are performed within the renormalized Quasiparticle Random Phase Approximation. Transitions to the first excited two-quadrupole phonon 0+ state are described within a boson expansion formalism. It is found that the 100Mo is a good candidate for experimental study of the 0 decay to excited 0+ state due to small suppression of this transition relative to the transition to the ground state.  相似文献   

19.
We present a zero magnetic field muon spin rotation study of-O2 (antiferromagnetic phase of solid oxygen) in the temperature range of 10–24 K. Static magnetic order has been observed below the- transition temperatureB =23.8 K. The temperature dependence of the muon precession frequency exhibits behavior characteristic of a two-dimensional Heisenberg spin-1 system with the anisotropy parameter 10–2 quite similar to that of antiferromagnetic phase of the high-temperature superconductor parent compounds. A unique local field at the muon site has been determined to beB 0=1.27(5) kG at low temperatures.  相似文献   

20.
The internal conversion coefficients were calculated for the 165.853 keV 5/2+7/2+ hindered transition in 57 139 La using the new computer program NICC for conversion coefficients of all atomic shells. The algorithm employed in this code is described. The analysis of precise experimental data yielded the nuclear penetration parameter=4.2±0.8. This value was found to be in accord with theoretical estimates and to correspond to the Nilsson deformation parameter=–0.056±0004 of the139La nucleus. Using the Nilsson wave functions for above the mixing ratio 2 = N(E2)/N(M1) was determined to be less than 8.10–5, which supports the assumption of a pureM1 multipolarity of this transition.Presented at the 26th All-Union Conference on Nuclear Spectroscopy and Nuclear Structure (February 1976, Baku, USSR).We are obliged to Dr. B. N.Subba Rao for the communication of his value for the investigated transition.  相似文献   

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