首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 78 毫秒
1.
Dirac's large numbers hypothesis (LNH) is incorporated into kinetic theory, statistical physics, and thermodynamics using the self-consistent formalism of units covariance. The ingeodesic equation and matter creation introduce modifications of the most fundamental laws of the subject. Liouville's theorem no longer holds, the Boltzmann equation is modified, as is theH-theorem. This affects the second law of thermodynamics in that for canonical LNH neither reversible nor adiabatic processes are possible (as expected). A significant result is that the collision terms have the same form as in standard physics. This means that equilibrium distribution functions are identical to those of standard physics, as required for self-consistency with the precepts of LNH. The net effect of LNH is as though all matter in our Universe were weakly coupled to a large heat bath.NAS-NRC Senior Research Associate 1981–1983.  相似文献   

2.
The physical origin of inertial forces is shown to be a consequence of the local interaction of Dirac's real covariant ether model(1) with accelerated microobjects, considered as real extended particlelike solitons, piloted by surrounding subluminal real wave fields packets.(2) Their explicit form results from the application of local inertial Lorentz transformations to the particles submitted to noninertial velocitydependent accelerations, i.e., constitute a natural extension of Lorentz's interpretation of restricted relativity.(3) Indeed Dirac's real physical covariant ether model implies inertial forces if one considers the real accelerated noninertial motions of general relativity, defined within the absolute local inertial frames associated with the observed local isotropy of the 2.7° K background microwave radiation.(4) Inertia thus appears as a necessary consequence of the real particle motions described by the E.d.B.B. formalism of quantum mechanics.  相似文献   

3.
The Compton channels for the production of axions γeea and neutrinos γ evv? in a magnetic field are examined on the basis of a two-dimensionally covariant formalism developed in this paper. Expressions are obtained for the cross sections of the processes as well as the power of the radiation per unit volume in a degenerate and nondegenerate electron gas. It is shown that the axion luminosity of white dwarfs on account of the Compton generation mechanism is at least four orders of magnitude less than the photon luminosity, and the axion luminosity for magnetic neutron stars approaches the neutrino luminosity in magnitude.  相似文献   

4.
In standard physics quantum field theory is based on a flat vacuum space-time. This quantum field theory predicts a nonzero cosmological constant. Hence the gravitational field equations do not admit a flat vacuum space-time. This dilemma is resolved using the units covariant gravitational field equations. This paper shows that the field equations admit a flat vacuum space-time with nonzero cosmological constant if and only if the canonical LNH is valid. This allows an interpretation of the LNH phenomena in terms of a time-dependent vacuum state. If this is correct then the cosmological constant must be positive.  相似文献   

5.
Simple analytical expressions are obtained for the rate of the inverse stimulated bremsstrahlung absorption under electron scattering from a Coulomb center with charge Z in the presence of the electromagnetic field. The initial and final values of electron energy are assumed to be small compared to the Rydberg energy Z 2 (atomic units are used throughout). Single-photon processes of absorption and induced radiation of photon by electron are treated. It is assumed that the electromagnetic field frequency ω is rather low, so that the condition Zω/p 3 ? 1, where p is the electron momentum, and the condition ?ω ? p 2 are valid. However, this frequency is assumed to be fairly high compared to the electron-Coulomb center collision frequency: ω ? v nei. The dependences of the rates of photon absorption and induced radiation on the angle θ between the direction of incident electron and the electromagnetic field polarization vector (assumed to be linearly polarized) are obtained. It is demonstrated that, for any angles θ, the rate of photon absorption is higher than the rate of induced radiation and, therefore, the Marcuse effect for slow electrons (electromagnetic field amplification) is absent. It is further demonstrated that a slow electron on the average absorbs double ponderomotive energy per collision with an ion (Coulomb center) in Maxwellian plasma. This agrees both with the known results calculation for fast electrons and with the known results of the calculation based on the classical Boltzmann kinetic equation for plasma.  相似文献   

6.
F. Debbasch  W.A. van Leeuwen 《Physica A》2009,388(9):1818-1834
In a preceding article we presented a general relativistic treatment of the derivation of the Boltzmann equation. The four-momenta occurring in this formalism were all on-shell four-momenta, verifying the mass-shell restriction p2=m2c2. Due to this restriction, the resulting Boltzmann equation, although covariant, turned out to be not manifestly covariant. In the present article we switch from mass-shell momenta to off-shell momenta, and thereby arrive at a Boltzmann equation that is manifestly covariant.  相似文献   

7.
A conformally covariant formulation of operator product expansion is discussed as an expansion of the product of two representations into a direct sum of irreducible representations. The basic irreducible representations are analyzed and classified. The isomorphism between the conformal algebra and the O(4, 2) algebra is used to obtain a manifestly covariant formalism. The implications of the isomorphism in the derivation of the representations is discussed. The covariant O(4, 2) formalism directly relates dominant terms to nondominant terms in the light-cone limit. The essential coincidence of the problem of a conformal covariant operator product expansion to the problem of determining the form of the three-point function is stressed, together with the relevance of a selection rule for two-point functions following from exact (not spontaneously broken) conformal covariance. The role of Ward identities in a conformal covariant scheme is pointed out, and the mathematical implications on the n-point functions from causality are described.  相似文献   

8.
《Physics letters. [Part B]》1986,174(3):233-237
Elastic charge and magnetic form factors of 3He, 17O, and 209Bi are calculated using a consistent relativistic formalism. The wavefunctions are generated by the self-consistent relativistic Hartree formalism, and a relativistically covariant effective current operator is used. Results are obtained for momentum transfers up to 7.5 fm−1.  相似文献   

9.
Photon polarization effects in Compton scattering on unpolarized electrons are calculated in the first Born approximation by using the covariant formalism. The general expressions are specialized with regard to the production of hardγ-rays by the scattering of laser photons by relativistic electrons. Results are given for various polarizations of the initial photon and three electron energies in the GeV region.  相似文献   

10.
Gravitation deflects light, which has been confirmed by a large number of observation data. f(R)-gravity is modification of Einstein’s gravity. According to the field equations obtained by the action of the f(R) form, a similar Schwarzschild metric is obtained. According to the condition that four-dimension momenta of the photon return to zero and conservation of covariant momenta, we obtain an equation of photon motion in a specific form of f(R)-gravity. We solve the equation to get gravitational deflection angle of light that grazes surface of sun and the calculation result is consistent with the experimental observation data.  相似文献   

11.
We evaluate the chiral anomaly for a gauge theory on Sn in the hyperspherical O(n + 1) covariant formalism using the method of Fujikawa and comment on related aspects.  相似文献   

12.
The physical characteristics of the 75Se radionuclide make it a promising gamma radiator for use as a brachytherapy sealed source. This radionuclide combines relatively low-energy photon radiation emitted during decay with a sufficiently long half-life (approximately 120 days) and the possibility of obtaining high specific activity. All this makes this radionuclide attractive for automated injection brachytherapy. The aim of this work was to study the dosimetric characteristics of 75Se for its potential use in high and medium dose rate brachytherapy. According to the TG-43 formalism, the radial dose function g(r) and the anisotropy function F(r, θ) are calculated. 75Se as a radionuclide for sealed source brachytherapy has many advantages over widely used isotopes and can serve as an alternative to iridium sources.  相似文献   

13.
14.
15.
We calculate the total and differential cross sections for radiative-collisional excitation of the metastable 21S state of He atoms at collisions with Ne atoms in external radiation fields of various frequencies and polarizations. The calculations are performed for a thermal collision energy of E = 10?3 atomic units and light intensity of I = 1 MW cm?2, which corresponds to a single photon absorption by a quasi-molecule during the collision. Both the differential and total cross sections are shown to depend strongly on the relative orientation of the radiation polarization vector and the initial relative velocity vector of the colliding atoms. We analyze the azimuthal scattering asymmetry related to the orientation of the angular momentum of the absorbed photon.  相似文献   

16.
Quantum electrodynamics with non-vanishing photon mass is written down in interaction representation. To apply the Wick decomposition formalism of theS-matrix one can introduce an indefinite metricη, similar to that of Gupta-Bleuler's quantum electrodynamics with vanishing photon mass. It will be shown that the complementary photons can be eliminated from the formalism with the help of the subsidiary condition. By a succeeding unitary transformation allx-singularities (x=photon mass) can be removed. The limiting processx→0, which then becomes possible, leads to the well-known so-called ‘reduced’ theory of quantum electrodynamics. A physical interpretation of this limiting process will be tried using, as a simple example, the radiation of an electric dipole.  相似文献   

17.
18.
Heavy meson,s- top-wave, weakb→c transitions are studied in the context of the heavy quark effective theory using covariant meson wave functions. We use the trace formalism to evaluate the weak transitions. As expected from heavy quark symmetry, the eight transitions betweens- andp-wave states are described in terms of only two universal form factors which are given in terms of explicit wave function overlap integrals. We present our results in terms of both invariant and helicity amplitudes. Using our helicity amplitude expressions we discuss rate formulae, helicity structure functions and joint angular decay distributions in the decays \(\bar B \to D^{**} ( \to (D,D^* ) + \pi ) + W^ - ( \to l^ - \bar v_l )\) . The heavy quark symmetry predictions for the one pion transitionsD **→(D,D *)+π are similarly worked out by using trace techniques.  相似文献   

19.
《Annals of Physics》1986,166(1):234-249
We continue the previous discussion (A. D'Adda, J. E. Nelson, and T. Regge, Ann. Phys. (N.Y.)165) of the covariant canonical formalism for the group manifold and relate it to the standard canonical vierbein formalism as pioneered by Dirac. The form bracket is related to the Poisson bracket of classical mechanics. We utilise systematically the calculus of differential forms and a compound notation which labels Poincaré multiplets. In this way we obtain a particularly clear and compact expression for the Hamiltonian and the constraints algebra of the vierbein formalism.  相似文献   

20.
An expression for n-photon cross-section ionization of hydrogenic atoms by intense linearly polarized light is obtained using the second quantification formalism for the radiation and the Green's function method. It is shown that it reduces into Stobbe's formula in the one photon case.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号