This volume contains papers presented at the Nuffield Workshop on supersymmetry and its applications held at Cambridge in the summer of 1985 and attended by many of the leading experts in the field. In physical terms, supersymmetry is a symmetry or gauge invariance which connects bosons (particles with integer spin) with fermions (particles with half integer spin). The study of supersymmetry has led to the construction of Yang-Mills theories, which are the first field theories to be free of the divergences that usually occur in quantum theories, with an infinite number of degrees of freedom. It has also led to the construction of supergravity and superstring theories which seem to be the best hope for a complete unified theory of all physical interactions including gravity. Supersymmetry and its Applications reviews a number of recent advances in the area of anomalies, the topology of gauge theories, superstrings, supergravity and super Yang-Mills theory.The papers, written by both physicists and mathematicians, include both expository articles and progress reports describing most recent developments.

We are all agreed that your theory is crazy. The question which divides us is whether it is crazy enough. Niels Bohr Superstring theory has emerged as the most promising candidate for a quan tum theory of all known interactions. Superstrings apparently solve a problem that has defied solution for the past 50 years, namely the unification of the two great fundamental physical theories of the century, quantum field theory and general relativity. Superstring theory introduces an entirely new physical picture into theoretical physics and a new mathematics that has startled even the mathematicians. Ironically, although superstring theory is supposed to provide a unified field theory of the universe, the theory itself often seems like a confused jumble offolklore, random rules of thumb, and intuition. This is because the develop ment of superstring theory has been unlike that of any other theory, such as general relativity, which began with a geometry and an action and later evolved into a quantum theory. Superstring theory, by contrast, has been evolving backward for the past 20 years. It has a bizarre history, beginning with the purely accidental discovery of the quantum theory in 1968 by G. Veneziano and M. Suzuki. Thumbing through old math books, they stumbled by chance on the Beta function, written down in the last century by mathematician Leonhard Euler.

This book provides a self-contained presentation of supergravity theories from its fundamentals to its most recent union with string and superstring theories, which are also reviewed in a self-contained manner. The subject is presented consistently in a unified geometric formalism, relying on the calculus of exterior forms and the mathematics needed to develop the theory is explained in appropriate chapters.