"This text aims to introduce the low-temperature phenomena of superfluidity and superconductivity from a unified viewpoint, with the existence of a macroscopic wave function stressed as the central principle. There is an extensive discussion of macroscopic theories, with major chapters on condensates and excitations, the two-fluid model, vortex states and Josephson effects. Superfluidity in the A and B phases of liquid 3He is described in terms of a microscopic theory of pairing of 3He atoms, and an introduction to the Ginzburg-Landau theory is also given. The authors' treatment of the Bardeen-Cooper-Schrieffer theory of superconductors covers a full chapter. Full descriptions of relevant experimental results are given throughout the book. The principle new feature of this third edition is the addition of a chapter on high-temperature superconductors, the most exciting development in the field in the last few years. The comprehensive survey of experiment and theory, supplemented by problems at the end of most chapters, makes this an invaluable foundation text for graduate students working in low-temperature physics, and its careful elaboration of basic principles will also make it accessible to final-year undergraduates taking specialised courses. In addition, anyone researching superfluids or superconductors would benefit from this systematic exploration of the similarities and contrasts between the two areas."--Page 4 of cover.