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1.
In recent papers the authors have discussed the dynamical properties of large Poincaré systems (LPS), that is, nonintegrable systems with a continuous spectrum (both classical and quantum). An interesting example of LPS is given by the Friedrichs model of field theory. As is well known, perturbation methods analytic in the coupling constant diverge because of resonant denominators. We show that this Poincaré catastrophe can be eliminated by a natural time ordering of the dynamical states. We obtain then a dynamical theory which incorporates a privileged direction of time (and therefore the second law of thermodynamics). However, it is only in very simple situations that this time ordering can be performed in an extended Hilbert space. In general, we need to go to the Liouville space (superspace) and introduce a time ordering of dynamical states according to the number of particles involved in correlations. This leads then to a generalization of quantum mechanics in which the usual Heisenberg's eigenvalue problem is replaced by a complex eigenvalue problem in the Liouville space.  相似文献   

2.
We consider a new expression for the dependence of mass on velocity, more general than the corresponding law of the special theory of relativity (STR). The deviations from the STR become large with increasing rest mass. One should therefore measure the dependence of mass on velocity for objects with a large rest mass. The theory predicts that particles with real mass can travel with hyperlight velocities. The space-time picture discussed here is close to Mach's conception: It is assumed that the dynamical behavior of a particle in uniform translational motion is due to the action of all the other masses in the universe. Space-time is eliminated as an active cause and, in contrast to the STR, is not absolute within the theory discussed here. It turns out that effects based on the new transformation formulas (from the coordinates and time in a stationary frame to the coordinates and time in a moving frame) are identical to those expected from the Lorentz transformations. For example, it is known that rapidly moving mesons decay with a longer half-life than stationary mesons and the STR describes this effect quantitatively. However, there is no strong evidence for the validity of the STR because the theory given in this paper predicts the same result.  相似文献   

3.
. .
The influence of an alternating magnetic field on the remanent state of magnetically soft materials
A study is made of the influence of an alternating magnetic field of varying maximum amplitude on the remanent state, or rather, apparent remanent state of toroidal and open samples of metallic and non-metallic magnetically soft ferromagnetics. An interpretation of the corresponding dependences is given on the basis of Kondorski's conception of the composition of a polycrystalline jerromagnetic material.
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4.
A theory of the azimuthal bunching of electrons injected into the betatron is presented and compared with the experiments described in [1]. The bunching is treated as a small perturbation of the stationary beam.The stationary injected beam is replaced by the corresponding equilibrium beam of the same perveance so that the angular velocity spread of the injected electrons is proportional to the square root of the injection perveance.Self-consistent wave solutions for the perturbation of the stationary solution are then found. Equations giving the amplification of small density or energy disturbances along the beam are derived. These disturbances are assumed to be introduced by density or velocity modulation of the injected beam. The condition for the spontaneous occurrence of bunching is deduced by assuming that the disturbances do not vanish even when there is no modulation of the injected beam. The resulting expressions for the threshold perveance and the rise-time of the disturbance are in reasonably good agreement with the experiments. Such agreement may be considered as further verification of the statement made in [1] that the amplification of the disturbances is caused by the negative mass instability mechanism.
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, . , [1]. . . , , . . , ., . , , . . , , [1].
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5.
The [, , ]-Langevin equation describes the time evolution of a real stationary process withT-positivity (reflection positivity) originating in the axiomatic quantum field theory. For this [, , ]-Langevin equation a generalized fluctuation-dissipation theorem is proved. We shall obtain, as its application, a generalized fluctuation-dissipation theorem for the one-dimensional non-linear diffusion process, which presents one solution of Ryogo Kubo's problem in physics.  相似文献   

6.
7.
, K 1 2 LP . 75°85° K , . , <80°. ( , ) <83°. , 90° , , , . >83° , , .
The influence of the spectral profile of theK12 doublet and diffraction broadening on the integrated intensities of high angle diffractions
Relations are derived giving the influence of the spectral profile of theK 1 2 doublet and the influence of diffraction broadening on the productLP of the Lorentz and polarization factor. The relations are used to calculate the numerical values of the corresponding corrections for the theoretical values of the integrated intensities of diffractions in the angular region 75°85° and for the most frequently usedK radiation of copper, cobalt and iron.It follows from the calculated values of the corrections that, due to the accuracy at present attainable in experimental measurements, the influence of the spectral profile in diffractions with an angle<80° can be neglected when calculating the theoretical values of the integrated intensities. The influence of diffraction broadening need not be taken into account in diffractions with an angle<83° even when the broadening is large (e. g. five-fold). As the angle approaches 90°, of eourse, the corrections for both above influences suddenly increase, particularly those for diffraction broadening, and their limitation becomes difficult and is not single-valued. For this reason the use of diffractions with angles>83° does not appear very suitable for solving problems based on exact measurement of the integrated intensities and their comparison with the corresponding theoretical values.
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8.
Unitary field theories and SUPER-GUT theories work with an universal continuum, the structured spacetime of R. Descartes, B. Spinoza, B. Riemann, and A. Einstein, or a (Machian (1–3) ) structured vacuum according the quantum theory of unitary fields (Dirac, (4,5) and Heisenberg (6–8) ). The atomistic aspect of the substantial world is represented by the fundamental constants which are invariant against all transformations and which depend on nothings (Planck (9–11) ). A satisfactory unitary theory has to involve these constants like the mathematical numbers. Today, Planck's conception of the three elementary constants , c, and G may be the key to general relativistic quantum field theory like unitary theory. However, the elementary constants are a question of measurement-theory, also.According to Popper's theory (12–16) of induction, such unitary theories are universal explaining theories. The fundamental constants involve the complementarity between the universal statements in unitary theory and the basic statements in the language of classical observables.  相似文献   

9.
We simulate the far-from-equilibrium irreversible expansion of a compressed ideal gas in two space dimensions. For this problem the particle trajectories from conventional smooth particle applied mechanics are isomorphic to those from a corresponding molecular dynamics simulation. The smooth-particle weight function used to describe the expanding gas is identical to the pair potential governing the molecular dynamics simulation. These many-body particle simulations are compared with those using a modified smooth-particle algorithm invented by Monaghan, as well as with those based on conventional grid-based Eulerian and Lagrangian methods.  相似文献   

10.
The results of a hypothetical experiment requiring a sequence of quantum measurements are obtained retrospectively, after the experiment has been completed, from a single reading of an apparatus register. The experiment is carried out reversibly and Schrödinger's equation is satisfied until the terminal reading of the register. The technique is illustrated using a feasible method of measuring photon spin as the quantum object observable and using the photon energy as the apparatus register. The technique is used to discuss the watchdog effect, the effect of repeated measurements inhibiting quantum jumps.  相似文献   

11.
, . . , °. K- , .
The meson decay of light hyperfragments
The binding energies of five types of light hyperfragments, i. e. of atomic nuclei of light elements containing one hyperon instead of one neutron, were measured. The hyperfragments originated by means of the interaction of K mesons with the nuclei of light elements, contained in the emulsion.
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12.
The controversial 2-d, 3-state chiral Potts model is studied using transfer matrix finite size scaling. at =0, we find dq N/dN –4/5, whereq is the wavevector, the chiral field, andN the strip width (N=4–10). The result is consistent with den Nijs's crossover exponent =1/6. With surface fields on the infinite free boundaries, exponents associated with bulk magnetizationy H, surface magnetizationy H, and surface susceptibility are computed vs. ; results are similar for or to the infinite direction. Preliminary results are given for the bulk specific heat critical amplitudes, to test the universality of amplitude ratios. The interface wetting line is located for 01/4 using simple transfer matrix calculations of surface tensions in the solid-on-solid approximation. Overhangs or bubbles seem relatively unimportant at all temperatures.  相似文献   

13.
14.
15.
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   

16.
17.
Let be an infinite dimensional Hilbert space and () the set of all (orthogonal) projections on . A comparative probability on () is a linear preorder on () such thatOP1,1O and such that ifPR,QR, thenPQP+RQ+R for allP, Q, R in (). We give a sufficient and necessary condition for to be implemented in a canonical way by a normal state onB(), the bounded linear operators on .  相似文献   

18.
19.
A study is made of the non-radiative transfer and diffusion of excitation energy in molecular crystals containing foreign molecules and its influence on the luminescent properties of these crystals.
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, .
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20.
We analyze the Schrödinger equation , whereH() is the hamiltonian of the molecular system consisting of nuclei with masses proportional to –4 and electrons with masses of order 1. Using the Born-Oppenheimer method we construct the leading order asymptotic expansion to the exact solutions of the equation. We show that if the particles interact through smooth potentials decaying suitably as the distance between particles tends to , then the expansion holds uniformly for all timest[0,). By similar analysis one can show validity of the expansion fort(–,0], thus our results hold for scattering theory.The material in this paper is contained in a dissertation submitted to the faculty of VPI & SU in partial fulfillment of the requirements for the Ph.D. degree.  相似文献   

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