This book presents the main mathematical methods of description and general problems in the theory of linear waves in dispersive systems and media, including equilibrium and nonequilibrium waves. To ...show how the general theory can be applied in practice, the authors give a unified description of the waves in all important physical systems which are traditionally studied in the mechanics of continuous media, electrodynamics, plasma physics, electronics and physical kinetics. Consideration is also given to the interaction of waves in coupled systems, the propagation and evolution of localized wave perturbations, and the emission of waves from dispersive media under the action of external sources moving in a prescribed manner. A general theory of instabilities of linear systems is given, in which the criteria for absolute and convective instabilities are formulated and compared, and Green's functions for some nonequilibrium media are calculated. Special attention is paid to problems in the theory of linear electromagnetic waves in plasmas and plasma-like media. The book also contains a number of original results of the present-day wave theory that have thus far been published in scientific journals only.
This book presents the main mathematical methods of description and general problems in the theory of linear waves in dispersive systems and media, including equilibrium and nonequilibrium waves. To ...show how the general theory can be applied in practice, the authors give a unified description of the waves in all important physical systems which are traditionally studied in the mechanics of continuous media, electrodynamics, plasma physics, electronics and physical kinetics. Consideration is also given to the interaction of waves in coupled systems, the propagation and evolution of localized wave perturbations, and the emission of waves from dispersive media under the action of external sources moving in a prescribed manner. A general theory of instabilities of linear systems is given, in which the criteria for absolute and convective instabilities are formulated and compared, and Green's functions for some nonequilibrium media are calculated. Special attention is paid to problems in the theory of linear electromagnetic waves in plasmas and plasma-like media. The book also contains a number of original results of the present-day wave theory that have thus far been published in scientific journals only.
We have solved the problem about the force with which an electromagnetic pulse in a liquid (or gaseous) medium at rest affects a solid body (also at rest) immersed in it. We have shown that under ...certain conditions (relating to the characteristics of the medium and the pulse shape), the formula for the force exerted per unit area of a body surface is obtained from the Landau - Lifshitz equations for static fields in the same way as, according to Pitaevskii, the field stress tensor is obtained from the static field stress tensor with the dispersion taken into account. The formula for the force acting on the wall, from which an incident quasi-monochromatic plane wave with a given intensity is reflected, differs from the corresponding formula for the case when the body is in a vacuum by the factor {+-}n{sub 1}, where n{sub 1} is the refractive index, and the upper (lower) sign corresponds to a positive (negative) group velocity of the wave in the medium. (laser applications and other topics in quantum electronics)