Results 241 to 250 of about 385,363 (284)

Spectral problem in a generalized theory of electromagnetic waves

2017 Progress In Electromagnetics Research Symposium - Spring (PIERS), 2017
It is shown theoretically that electromagnetic process is potentially-vortex. This extends Maxwell's theory. We detected four-dimensional vector potential which is a fundamental characteristic of the electromagnetic field. It has been shown that it describes unambiguously a velocity field of physical vacuum in the selected frame.
G. G. Islamov, A. K. Tomilin
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Uniform Electromagnetic Field in the Theory of General Relativity

Physical Review, 1959
A cosmological solution of the Einstein-Maxwell's field equations, corresponding to the case of a uniform (that is, covariant constant) electromagnetic field, is derived by means of simple geometrical arguments; the Riemannian manifold it corresponds to is the product of two ordinary surfaces of constant curvature, whose type and radius depend on the ...
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Theory of Electromagnetic Generation of Transverse Ultrasound in Ferromagnets

International Journal of Applied Electromagnetics and Mechanics, 1993
Theoretical study of the processes of electromagnetic excitation of transverse ultrasound in hexagonal magnetics is presented. It is shown, that the amplitude of ultrasound excited sharply increases at ferromagnetic resonance frequency. At frequencies far from ferromagnetic resonance the generation peak took place at the magnetoelastic resonance ...
A.N. Vasil'ev, YD. Buchelnikov
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Electromagnetic radiation in the general theory of relativity. I

Soviet Physics Journal, 1973
The possibilities are investigated for the joint solution of Einstein's and Maxwell's equations for an isotropic electromagnetic field. Three groups of metric forms of space are shown, in which such a solution is permissible.
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General Theory of Interaction of Electromagnetic Fields with Matter

1994
The electromagnetic field is described by two vectors e and h, that is, by the macroscopic strengths of the electric and magnetic fields. These are the exact instantaneous values of the fields at a given point at a specific moment of time. We denote the averaged fields in the medium by e and H.
Yu. A. Il’inskii, L. V. Keldysh
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The Hamiltonian of the General Theory of Relativity with Electromagnetic Field

Physical Review, 1950
In this paper we have given a specific example of a Hamiltonian of a non-linear field theory, a Hamiltonian density completely free of time derivatives. In accordance with the general theory developed previously, this Hamiltonian is one of the constraints between the canonical variables and, therefore, vanishes everywhere.
Bergmann, Peter G., Penfield, Robert, Schiller, Ralph, Zatzkis, Henry   +3 more
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On the theory of electromagnetic generation of ultrasound in metals

Solid State Communications, 1980
Abstract The expressions obtained in [1–4] for the electron force acting in metals have been discussed and compared. It has been shown that for free electrons these expressions coincide and the discrepancy is due to the incomplete register of the bound structure effects in [2, 3].
E.A. Kaner, V.L. Falko
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6-Optics and a general theory of gravitation and electromagnetism

Soviet Physics Journal, 1984
It is shown that the equation of motion of material particles in a curved spacetime in the presence of electromagnetic field, known from general relativity, is equivalent to an equation for a geodesic line in a 6-dimensional Riemannian manifold of signature (+----+), at least when a special choice of the 6-metric has been made.
Yu. S. Vladimirov, A. A. Kozlenkov
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Theory of the anomalous electromagnetic generation of ultrasound in aluminum

Physical Review B, 1978
Anomalies observed in electromagnetic generation of ultrasound in aluminum are explained on the basis of known Fermi-surface geometry. At large values of ${\ensuremath{\omega}}_{c} \ensuremath{\tau}$ the topology of the second-zone hole sheet permits only holelike cyclotron orbits, while for small values of ${\ensuremath{\omega}}_{c} \ensuremath{\tau}$
N. C. Banik, A. W. Overhauser
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Generalized-ray theory for electromagnetic fields in layered media

2013
Generalized-ray theory for time-domain electromagnetic fields in a horizontally layered medium is developed. After introducing appropriate integral transformations and source-type field representations in vertically inhomogeneous media, the solution is written out in terms of generalized ray constituents whose space-time counterparts are constructed ...
Štumpf, M. (author), De Hoop, A.T. (author), Vandenbosch, G.A.E. (author)   +2 more
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