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81.
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   
82.
Within the framework of general relativity a dynamics of homogeneous anistropic axially symmetric model of the Bianchi type I is considered for the case when sources of gravitational field are ultrarelativistic matter, homogeneous magnetic field, and fluxes of free particles. Qualitative analysis of the field equations on a phase plane is given. All solutions of a considered type for large values of proper time asymptotically approach the flat Friedmann model while the value of energy density of free particles approaches the double value of magnetic field energy density. Near a singular state the solution exhibits oscillating behavior with successive interchange of Kasner singularities of pancake-like and filament-like types. It is also shown that in the absence of matter a solution retains its character.  相似文献   
83.
84.
Shikin  E. V. 《Mathematical Notes》1973,14(2):707-710
On the x0y plane let there be specified a complete metric of negative curvature K by means of the line element ds2=dx2+B2(x, y) dy2, and, in the strip a={0xa, -4-bounded function B>0,K-2<0 ( and are constants). Then, the metric in strip a is embedded in R3 by means of a surface of class C3.Translated from Matematicheskie Zametki, Vol. 14, No. 2, pp. 261–266, August, 1973.  相似文献   
85.
Exact self-consistent plane-symmetric solutions of the spinor-field equation with zero mass parameter and a nonlinear term that is an arbitrary function of the invariant , are obtained in gravitation theory. An equation with power-law nonlinearity in which the nonlinear term in the spinor-field Lagrangian has the form LN=λP2n, where λ is the nonlinearity parameter and n=const, is investigated in detail. It is shown that λ=−Λ2<0, n>1, the original system of Einstein and nonlinear spinor-field equations has regular solutions with a localized spinor-field energy density. Here the soliton-like configuration of the fields possesses a negative energy. Exact solutions are also obtained for the above spinor-field equation in flat spacetime, and it is demonstrated that there are no soliton-like solutions in that case. Thus it is established that the proper gravitational field plays a decisive, controlling role in the formation of soliton-type solutions of the above nonlinear spinor-field equation. Russian International Friendship University. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 7, pp. 48–53, July, 1997.  相似文献   
86.
The results of investigations of the electronic energy structure and physicochemical properties of nanostructured systems by optical and photoelectron spectroscopy using synchrotron radiation are briefly reviewed. The quantum-size effect in thin metal films and surface lateral superlattices are analyzed. The effect of structural defects on the chemical state of metal clusters on the surface of oxides in catalytically active systems is discussed. The results of the study of the specific features of chemical bonding in solid-state nanostructures within the quasi-molecular approach are presented. The possibility of using biological structures (proteins) as matrices for the formation of ensembles of nanoclusters is considered.  相似文献   
87.
88.
Journal of Experimental and Theoretical Physics - The influence of manganese atom intercalation on the electronic structure of graphene grown on Au/Co(0001)/W(110) and SiC(0001) substrates is...  相似文献   
89.
The problem of matter creation in the early Universe is considered in terms of quantum cosmology, introducing interactions of the scalar field with the spinor and vector fields of matter.  相似文献   
90.
We have investigated the details of the eigenmode for a resonator containing a two-dimensional electron system (2DES) formed on the surface of liquid helium. We show that anticrossing phenomena occur near the crossing point ω0c, where ω0 is the eigenmode of the resonator and ωc is the cyclotron frequency. The structure of the coupling constant is established. It is a flexible parameter, i.e., sensitive especially to magnetic field and electron density. A finite coupling leads to a perturbation, δω, of the eigenmode of the resonator in presence of the 2DES. Corresponding calculations and measurements of δω are presented. The theory fits the experimental data. The influence of anticrossing on the cyclotron resonance absorption line shape is demonstrated.  相似文献   
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