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1.
The possible existence of a vector leptonic resonance (0) in the + system is considered. We discuss the effect such a resonance would have on the g factor of the muon and also on the ratio of the partial widths of the muonic and electronic decay modes (RV = (V +)/G (V e+ e)) of the neutral vector mesons 0,,,, and. From the experimental values of R and R, the following values are obtained for the mass, coupling constant, and partial decay widths of the resonance: M = 872 ± 60 MeV, f2/4 = 4 ± 2) ·10–4, ( 0 + ) = 0.12±0.06 MeV, and (0 0 +) = 0.13±0.06 MeV.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 5, pp. 39–43, May, 1977.  相似文献   

2.
The central limit theorem of Cushen and Hudson is reformulated on the algebra of the CCR. Namely, for a gauge invariant state , the weighted convolutions n of the central limit tend to the quasi-free reduction Q of pointwise. It is proved that if the initial relative entropy S(, Q ) is finite, then S( n , Q ) goes to 0 and so n Q 0. No restriction on the dimension of the test function space is made.  相似文献   

3.
A practical method is described for determining the symmetry groups of the differential equations of physics via a discussion of all possible operators in space of coordinates {x} and derivatives {/x}. The Lie-algebra operators on the solutions are sought. The problem is solved by successively complicating the form of the operators.  相似文献   

4.
A new expression e is obtained for resonance in the reaction e+e ar + with allowance for the radiative corrections, which also contain the emission of hard photons by the final leptons and the final value of the energy resolution E. An expression is obtained for the total probability of radiative lepton decay. A numerical analysis of the experimental data is made for the reaction +, and the parameters e+e (3, 1) e+e, and e 2 /, e, and are determined for (3, 1) resonance-with allowance for the radiative corrections.This paper was read (November 17–21, 1975) at a session on high-energy physics of the Department of Nuclear Physics of the Academy of Sciences of the USSR.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 3, pp. 29–34, March, 1977.  相似文献   

5.
LetH N be the quantum mechanical Hamiltonian for a neutral system of 2N charged particles, each of unit charge. The HamiltonianH N is assumed to act on wave functions inL 2(6N ) which satisfy Bose statistics. It is shown that if the kinetic energy of is sufficiently small, then |H N |–CN 7/5 for some universal constantC.Research supported by U.S. National Science Foundation Grant DMS 8600748  相似文献   

6.
, , . , , — r –3/4 r 1/2.
Excitation of high frequency oscillations of electron plasma by a diverging beam
The problem of the stability of high frequency oscillations of electron plasma is investigated in the hydrodynamical approximation. The oscillations are supposed to be excited by a beam of electrons outgoing from a spherical or cylindrical surface. The regions of instability in the spectrum of frequencies are found and it is shown that the amplitude of the oscillations increases as a power of the distance (in the case of spherical symmetry) or asr –3/4 expr -1/2 (cylindrical symmetry).
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7.
We consider a system of nonlinear spinor and scalar fields with minimal coupling in general relativity. The nonlinearity in the spinor field Lagrangian is given by an arbitrary function of the invariants generated from the bilinear spinor forms S= and P=i5; the scalar Lagrangian is chosen as an arbitrary function of the scalar invariant = ,,, that becomes linear at 0. The spinor and the scalar fields in question interact with each other by means of a gravitational field which is given by a plane-symmetric metric. Exact plane-symmetric solutions to the gravitational, spinor and scalar field equations have been obtained. Role of gravitational field in the formation of the field configurations with limited total energy, spin and charge has been investigated. Influence of the change of the sign of energy density of the spinor and scalar fields on the properties of the configurations obtained has been examined. It has been established that under the change of the sign of the scalar field energy density the system in question can be realized physically iff the scalar charge does not exceed some critical value. In case of spinor field no such restriction on its parameter occurs. In general it has been shown that the choice of spinor field nonlinearity can lead to the elimination of scalar field contribution to the metric functions, but leaving its contribution to the total energy unaltered.  相似文献   

8.
Einstein's equations are rewritten in terms of a certain torsionless linear connection which differs, in general, from the Levi-Civita metric connection . The torsionless connection appears in a natural way as the canonical momentum of the gravitational field g . Einstein's equations have a simple interpretation in terms of the connection . The equivalence of the so-calledpurely metric, purely affine, andmetricaffine theories of gravitation is proved.This work has been written under the financial support of Gruppo Nazionale per la Fisica Matematica of the Italian National Research Council.  相似文献   

9.
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   

10.
The gyroscope in an orbiting satellite will be acted on by additional gravitational fields due to the rotation of the earth and due to the orbital velocity of the satellite. According to special relativistic gravitational theory, we deduce L (S) —the gyroscope's precession rate due to the orbital velocity—and S (S) —the gyroscope's precession rate due to the earth's rotation in the polar orbit case. The results are L (S) = (2/3) L (G) , S (S) = (3/2) cos (1 - sin2 cos2)1/2 S (G) , where and are the gyroscope's polar angles, and L (G) and S (G) are the geodetic and frame-dragging precession rates predicted by general relativity, respectively.  相似文献   

11.
A distinction is made between two wave functions(x) and(x), The former describing a continuous distribution of electronic matter for a single system, the latter describing the regularities in repeated experiments. The classical field(x) necessarily includes the self energy and accounts for all the radiative processes without the probability interpretation.  相似文献   

12.
Based on the (relativistic) Maxwell equations with displacement current E/t, the initial-boundary-value problem for the compression of an initially homogeneous magnetic fieldB={0,B(x,t),0} between a fixed liner atx=0 and a detonation-driven liner atx=s(t) is solved analytically. By homogenizing the boundary conditions at the moving boundary, the transient electromagnetic fields are shown to be a superposition of quasistatic elliptic (E/t=0) and hyperbolic (E/t0) wave solutions. The wave equation is solved by a Fourier expansion in time-dependent eigenfunctionsf n =f n [nx/s(t)] for the variable region 0xs(t), where the Fourier amplitudes n (t) are determined by coupled differential equations of second order. It is concluded that the conventional elliptic flux compression theories (E/t=0) hold approximately for nonrelativistic liner speeds , whereas the hyperbolic theory (E/t0) is valid for arbitrary liner speeds .  相似文献   

13.
The extreme relativistic limit (E-representation) of the wave equation in the Schrödinger formi/t =H describing particles and anti-particles of spin s and non-zero rest mass m is presented here. As the wave function has just the minimum number of 2(2s+1) components, the necessity of avoiding redundant components by auxiliary conditions does not arise. Relevant expressions are given for the infinitesimal generators of the Poincaré group and for the operators representing the observables in this representation.  相似文献   

14.
In terms of the Dirac operator P, we introduce on any field a first-order operator D and show that the operator (–) on the spinors (=(n/4(n–1))R; dim W=n) is positive. By means of a universal formula, we show that, on a compact spin manifold of dimension 3, the Hijazi inequality [8] holds for every spinor field such that (P, P) = 2(, ) (=const.). In the limiting case, the manifold admits a Killing spinor which can be evaluated in terms of . Different properties of spin manifolds admitting Killing spinors are proved. D is nothing but the twistor operator.  相似文献   

15.
In the study of the formulation of Maxwellian tails the nonlinear partial differential equation 2 u/x +u/x+u 2=0 arises. We determine the Lie point symmetry vector fields and calculate the similarity ansätze. Then we discuss the resulting ordinary differential equations. Finally, the existence of Lie Bäcklund vector fields is studied and a Painlevé analysis is performed.  相似文献   

16.
17.
In this paper we concern ourselves with the small asymptotics of the inner products of the eigenfunctions of a Schrödinger-type operator with a coherent state. More precisely, let j and E j denote the eigenfunctions and eigenvalues of a Schrödinger-type operator H with discrete spectrum. Let (x,) be a coherent state centered at the point (x, ) in phase space. We estimate as 0 the averages of the squares of the inner products ( a (x,) , j ) over an energy interval of size around a fixed energy, E. This follows from asymptotic expansions of the form for certain test function and Schwartz amplitudes a of the coherent state. We compute the leading coefficient in the expansion, which depends on whether the classical trajectory through (x, ) is periodic or not. In the periodic case the iterates of the trajectory contribute to the leading coefficient. We also discuss the case of the Laplacian on a compact Riemannian manifold.Research supported in part by NSF grant DMS-9303778  相似文献   

18.
For { y },y, a one parameter family of invertible Weyl operators of possibly non-zero index acting on spinors over an even dimensional compact manifoldX, we express the phase of the chiral determinant det in terms of the invariant of a Dirac operator acting on spinors over ×X.Supported in part by NSF Grant No. PHY-82-15249Supported in part by NSF Grant PHY 8605978 and the Robert A. Welch Foundation  相似文献   

19.
Many one-dimensional quasiperiodic systems based on the Fibonacci rule, such as the tight-binding HamiltonianH(n)=(n+1)+(n–1)+v(n) (n),n,l 2(),, wherev(n)=[(n+1)]–[n],[x] denoting the integer part ofx and the golden mean , give rise to the same recursion relation for the transfer matrices. It is proved that the wave functions and the norm of transfer matrices are polynomially bounded (critical regime) if and only if the energy is in the spectrum of the Hamiltonian. This solves a conjecture of Kohmoto and Sutherland on the power-law growth of the resistance in a one-dimensional quasicrystal.  相似文献   

20.
, . . . , , . , . , . .
Betatron oscillations in an accelerator with a general field I
The paper gives a linear theory of equilibrium trajectories in an accelerator with a generalized magnetostatic field, the components of which are defined on a general rotation surface. Equations of motion of the particles in natural coordinates are derived with respect to the change in energy and dissipative force. A system of equilibrium trajectories is found in the general form. Conditions for the field components on the reference surface, necessary for the existence of equilibrium trajectories, for the conservation of their geometric similarities and for maintaining the constancy of the frequencies of the betatron oscillations, are derived. A condition is also derived which must be satisfied by the reference surface in order to conserve constant circular frequency of the particles. It is seen that it is not possible to find a field for an accelerator with an exactly constant circular frequency and with constant frequencies of the betatron oscillation in the relativistic energy region. An ultra-relativistic cyclotron with such properties is realizable.
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