The book reviews a large number of 1- and 2-dimensional equations that
describe nonlinear phenomena in various areas of modern theoretical and
mathematical physics. It is meant, above all, for physicists who
specialize in the field theory and physics of elementary particles and
plasma, for mathe- maticians dealing with nonlinear differential
equations, differential geometry, and algebra, and the theory of Lie
algebras and groups and their representa- tions, and for students and
post-graduates in these fields. We hope that the book will be useful
also for experts in hydrodynamics, solid-state physics, nonlinear optics
electrophysics, biophysics and physics of the Earth. The first two
chapters of the book present some results from the repre- sentation
theory of Lie groups and Lie algebras and their counterpart on
supermanifolds in a form convenient in what follows. They are addressed
to those who are interested in integrable systems but have a scanty
vocabulary in the language of representation theory. The experts may
refer to the first two chapters only occasionally. As we wanted to give
the reader an opportunity not only to come to grips with the problem on
the ideological level but also to integrate her or his own concrete
nonlinear equations without reference to the literature, we had to
expose in a self-contained way the appropriate parts of the
representation theory from a particular point of view.