Description This book offers an elementary and unified introduction to the non-perturbative results obtained in relativistic quantum field theory
based on classical soliton and instanton solutions. Such solutions are derived for a variety of models and classified by topological
indices. The methods are then developed for quantizing solitons to obtain quantum particles. Vacuum tunneling, υ-vacua and the
dilute-instanton-gas approximation are described in detail. Other instanton effects related to quark-quark forces, confinement, the
U(1) problem and Borel summability are also discussed. The emphasis is on presenting the basic ideas in a simple pedagogical way. Technical
tools like functional methods, Grassman integrals, homotopy classification, collective co-ordinates etc. are developed ab initio.
The
presentation of this work is kept at a fairly simple level and ideas are developed through illustrative examples. Techniques not covered
in older field theory textbooks, such as functional integral methods, are presented in some detail to the necessary extent. These techniques
are important in their own right. Although the book is mainly addressed to particle physicists and quantum field theorists, several
portions will be of relevance to other branches of physics, particularly statistical mechanics. These include three chapters devoted
to deriving classical soliton and instanton solutions and one on collective co-ordinates, as well as sections devoted to general techniques.
