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1.
The quantum harmonic oscillator is described in terms of two basic sets of coordinates: linear coordinates x, px and angular coordinates ei, P (action-angle variables). The angular coordinate ei is assumed unitary, the conjugate momentum p is assumed Hermitian, and ei and p are assumed to be a canonical pair. Two transformations are defined connecting the angular coordinates to the linear coordinates. It is found that x, px can be physical, i.e., Hermitian and canonical, only under constraints on the p eigenvalue spectrum. The conclusion is that ei can be a unitary operator. A parallel analysis of the classical harmonic oscillator is done with equivalent results.  相似文献   

2.
The continuum form of the Gauss-Hertz principle is extended to include the time domain as well as space. The Schrödinger equation and general relativity are derived by this method. The equivalence of the principle is shown to that of the Hamiltonian method where the energy is the expression –[ 2 +A·2 A], with being the difference between the acceleration potential and potential energy density, andA being the difference between the vector potentials of the acceleration field and the force field. The goal of Hertz to demonstrate a third arrangement of the principles of mechanics...which starts with... time, space and mass has apparently been achieved for relativity and for quantum mechanics, in addition to those classical equations previously found.  相似文献   

3.
The newly proposed anisotropic fiber structures with cylindrical polar principal axes appear to be an interesting novel class of special lightguides. In this paper, some interesting results relating to such fibers are derived which, to the knowledge of this author, have not yet been reported in the literature. It is found that, ifn c0 ( )1/2>n zc0( r )1/2, TE01 will be the fundament mode with a range of single-mode operation given by 2.61n zc0 (2 r )1/2 /a<2.61n c0(2 )1/2. On the other hand, ifn zc0 ( r )1/2>n c0( )1/2, then TM01 becomes the fundamental mode whose single-mode operation range is 2.61n c0 (2 )1/2 /a<2.61n zc0(2 r )1/2.  相似文献   

4.
The k theory is compared with the multilinear theory of scalar fields 1, 2, ..., k having the same mass as that of . In particular, it is shown that Feynman integrals encountered in the 3 theory are not necessarily present also in the 1 2 3 theory, but they are if they correspond to planar Feynman graphs having no tadpole part. Furthermore, a necessary and sufficient condition for the presence of a 3 Feynman integral in the 1 2 2 theory is found. Those considerations are applications of graph theory, especially of the coloring problem of graphs, to Feynman graphs.  相似文献   

5.
Consider a gauge fieldF and a scalar field with a self-couplingV() as well as the standard coupling betweenF and . If 02V()·V(), there are no classical lumps. IfV()=||4 the system is conformally invariant and all the energy radiates out along the light cone.Research supported in part by NSF grants MCS 77-01340 and MCS 78-03567  相似文献   

6.
We demonstrate with the example of Cahn-Hilliard dynamics that the macroscopic kinetics of first-order phase transitions exhibits an infinite number of constants of motion. Moreover, this result holds in any space dimension for a broad class of nonequilibrium processes whose macroscopic behavior is governed by equations of the form /t = W(), where is an order parameter,W is an arbitrary function of , and is a linear Hermitian operator. We speculate on the implications of this result.  相似文献   

7.
We analyze the long time behavior of an infinitely extended system of particles in one dimension, evolving according to the Newton laws and interacting via a non-negative superstable Kac potential (x)=(x), (0, 1]. We first prove that the velocity of a particle grows at most linearly in time, with rate of order . We next study the motion of a fast particle interacting with a background of slow particles, and we prove that its velocity remains almost unchanged for a very long time (at least proportional to –1 times the velocity itself). Finally we shortly discuss the so called Vlasov limit, when time and space are scaled by a factor .  相似文献   

8.
Consider a viscous incompressible fluid in the half-plane and letu t be a solution of the Navier-Stokes equation. In this paper we prove that the product formula (E t/n G t/n u) n u 0, whereE t is the Euler flow,G t is the heat flow and is a suitable operator describing the vorticity production due to the boundary, converges uniformly tou t in the limitn .Research supported by Ministero della Pubblica Istruzione, CNR contract No. 84.00016.02 and GNFM  相似文献   

9.
A variety of rigorous inequalities for critical exponents is proved. Most notable is the low-temperature Josephson inequalitydv +2 2–. Others are 1 1 +v, 1 1 , 1,d 1 + 1/ (for d),dv, 3 + (for d), 4 , and 2m 2m+2 (form 2). The hypotheses vary; all inequalities are true for the spin-1/2 Ising model with nearest-neighbor ferromagnetic pair interactions.NSF Predoctoral Fellow (1976–1979). Research supported in part by NSF Grant PHY 78-23952.  相似文献   

10.
In this paper we have obtained the general vacuum solution for Bianchi type V in the Brans-Dicke theory. It is shown that for the special case=0, the sourceless scalar field is dynamically an essential factor which determines the cosmological expansion parametersR i and the singularity does not occur whent=0. For this solution there is no antigravity (>0), which disagrees with other solutionsa for BDT-Bianchi type V  相似文献   

11.
Scale invariance is considered in the context of gravitational theories where the action, in the first order formalism, is of the form S= L 1 d 4 x+ L 2 d 4 x where the volume element d 4 x is independent of the metric. For global scale invariance, a dilaton has to be introduced, with non-trivial potentials V()=f 1 e in L 1 and U()=f 2 e 2 in L 2 . This leads to non-trivial mass generation and a potential for which is interesting for inflation. Interpolating models for natural transition from inflation to a slowly accelerated universe at late times appear naturally. This is also achieved for Quintessential models, which are scale invariant but formulated with the use of volume element d 4 x alone. For closed strings and branes (including the supersymmetric cases), the modified measure formulation is possible and does not require the introduction of a particular scale (the string or brane tension) from the begining but rather these appear as integration constants.  相似文献   

12.
The existence and analyticity of the correlation functionals of a quantum lattice in the infinite volume limit is proved. The result is valid at sufficiently high temperatures and for a large class of interactions. Our method estimates the kernelK for a set of Kirkwood-Salzburg equations. While a naive estimate would indicate that K =, we take into account cancellations between different contributions toK in order to show that for sufficiently high temperatures K <1, and this estimate is independent of the volume of the system.Supported in part by the Air Force Office of Scientific Research.  相似文献   

13.
In a previous paper asymptotic creation and annhilation operatorsa ± # have been constructed by the Kato-Mugibayashi method from the creation and annihilation operatorsa # for spin 1/2 fields with an interaction Hamiltonian density which is an evendegree polynomial in the field with ultra-violet cut-off and its derivatives. For any eigenvector of the total HamiltonianH=H 0+H I partial isometries ± have been defined so thata ± # equal ± a # *± on the ranges ± of ±. Since the existence of a groundstate ofH has been proved, the existence of at least one pair ± follows. The purpose of this paper is to show that for any ± orthogonal to the distribution of spins and momenta of the interacting Schrödinger states exp[–itH]± approaches fort the distributions of spins and momenta of the free state exp[–itH 0] if a wave-amplitude renormalization is carried out in ±. This is achieved by studying the expectation values of the operators in themaximally abelian W*-algebra generated by operators of the form a*a, in terms of whichany information about spins and momenta can be expressed.Supported in part by the National Research Council of Canada.  相似文献   

14.
The nonlinear wave equation, tt –+3=0, has many solutions that are periodic in time and localized in space, all with infinte energies. The search for spherically symmetric solutions that are well represented by the simple approximation, (r, t)A(r) sin t, leads to a discrete spectrum of solutions{ N (r, t; )}. The solutions are nonlinear wavepackets, and they can be regarded as particles. The asymptotic theory () of the motion of the guiding center of theNth wavepacket, in the presence of a specified potential, is characterized by an infinite mechanical mass and an infinte interaction mass, and they are compatible. The rest mass in the classical relativistic mechanics of guiding centers ism 0 c 2= N ; i.e. the spectrum { N } determines a spectrum of Planck's constants.On leave (1972–73) Université de Paris VI, Département de Mécanique, 75 Paris 5e, France.  相似文献   

15.
Let t be an analytic solution of the Schrödinger equation with the initial condition . Let t be the solution of the Schrödinger equation with the initial condition =, where is an analytic function. When 0, then t (x) t (x)1 ( t (x)), where t (x) trajectory starting from x. We relate this result to Feynman's sum over trajectories and complex stochastic differential equations.  相似文献   

16.
It is shown that if the Brans-Dicke equations have the solution,g ij generated by the trace free sourceT n (T-O) then there exists an adjoint solution –1, 2gij of these equations generated by the source -2 T u. An example is considered.  相似文献   

17.
No Heading The interplay between the tracial property and minimality of dispersions of states on projections of von Neumann algebras and C*-algebras is investigated. Let be a state on a C*-algebra A with the projection structure P(A). The dispersion () is defined as () = sup{(p) – (p)2 | p P(A)}. It is proved that () 2/9 whenever is a state on a real rank zero C*-algebra with no nonzero abelian representation. New characterization of traces in terms of dispersions is proved: A state on a von Neumann algebra without abelian and Type I2 direct summands is a trace if and only if has the minimal dispersion on all 3x3 matrix substructures. A similar characterization of semifinite normal traces on von Neumann algebras is obtained. The connection between unitary invariance of states and minimal dispersion property on C*-algebras is studied. Besides providing a new characterization of trace in terms of physically relevant properties, the existing results on hidden variables in W*- and C*-formalism of quantum mechanics are strengthen.  相似文献   

18.
The well-known connection between the SU(2) gauge theory and the massless 4 theory is extended to theories with nonzero mass. Elliptic solutions of these massive theories are given. These are of the plane-wave variety, with independent variable u=p·x where p is a constant four-vector. They depend on a free parameter k. Two of the solutions are generalized plane-waves while the third describes fluctuations about the vacuum solution.  相似文献   

19.
In this paper we investigate a number of analytical solutions to the polynomial class of nonlinear Klein-Gordon equations in multidimensional spacetime. This is done in the context of classical 4 and 6 field theory, the former with and without the inclusion of an external force field conjugate to . Both massive (m0) and massless (m=0) cases are considered, as well as tachyonic solutions allowed (v>c). We first present a complete set of translationally invariant solutions for the 4 model and demonstrate the role of external force fields in altering the form of these solutions. Next, spherically symmetric solutions are discussed in both 4 and 6 cases since they provide the most realistic models of elementary particles.  相似文献   

20.
In this paper we propose a new theory of a fiber bundle provided with a local metric of internal space. The fibers differ from usual fibers, having an enlarged factor. The enlargement may be procured by a differential mapping(x) from structure groupG to the fiberF x atx M, and(x)R. The torsion presented stems from the local metric of internal space and the local metric stems from a induced mapping *(x) of(x). From the theory we can get the Brans-Dicke theory with torsion. If we assume the spin density of the gauge field determines the enlarged factor of the fiberF x, our theory is an extended Cartan theory.  相似文献   

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