This book is concerned with a single group of quantum liquids, normal Fermi liqztids, discussing the nature of elementary excitations, the central concept of response functions. It is intended as a text for a graduate course in quantum statistical mechanics or low temperature theory.

This book is a very early systematic treatment of the application of the field-theoretical methods developed after the Second World War to the quantum mechanical many-body problem at finite temperature. It describes various techniques that remain basic tools of modern condensed matter physicists.

This volume is devoted to the theory of superfluid quantum liquids, describing the Landau theory of a neutral Fermi liquid in order to illustrate, in comparatively elementary fashion, the way both quantum statistics and particle interaction determine system behavior.

This book provides a unified account of the theory of quantum liquid and discusses the mathematical theory of linear response and correlations. It is helpful for experimental physicists working in the fields of low-temperature or solid-state physics.

This text continues to fill the need to communicate the present view of a solid as a system of interacting particles which, under suitable circumstances, behaves like a collection of nearly independent elementary excitations. In addition to introducing basic concepts, the author frequently refers to experimental data. Usually, both the basic theory and the applications discussed deal with the behavior of '`'simple' metals, rather than the '`'complicated' metals, such as the transition metals and the rare earths. Problems have been included for most of the chapters.

The Santa Fe Institute, as key element in its founding activities, sponsored two workshops on 'Emerging Syntheses in Science.' There was unanimous agreement among the participants that Professor Gell-Mann's keynote address and the ensuing talks were of such high quality and general interest that it would be highly desirable to publish these for bro