Physical premises for the construction of basic models

Abstract

The multitude of objects in which AWP have been observed is far too great to dwell on the construction and analysis of mathematical models for each of them. Their common features, with respect to AW phenomena, are revealed in the structure of simplified basic models which are analysed in the subsequent chapters of this book. Evidently, a model must be a sort of a “sketch” of the system concerned, so that it can be studied with a fair degree of completeness and the results obtained would be relevant to a wide class of objects. The basic models considered below meet this requirement. On the other hand, one should bear in mind the limits of applicability of the results obtained in this way to concrete objects. To this end, one should have, of course, a sufficiently complete mathematical description of the object in view, to be able to compare it with the corresponding basic model. Meanwhile, some essential limitations can be considered from a general point of view. These aspects are the subject of the present Chapter where we deal with mathematical models for systems with finite transport velocities, direct interactions between remote elements, AWPs in media with anisotropy in the transport phenomena and with mutual diffusion of the system components.