Focuses on an important aspect of this highly diversified area of condensed state physics: the one-body approximation in the theory of disordered systems. It describes the scope of problems within the framework of this approximation, its use in formulating several basic concepts, and its value in revealing many characteristic features of disordered systems. The book's main focus is on the density of states and the space-time correlation functions, and on their basic thermodynamic and kinetic characteristics. Among the many areas explored are the general properties of the one-body models frequently used and descriptions of selected one-dimensional problems, including closed dynamical equations; these are then used to thoroughly explore the density of states for several systems. In addition, some of the more complex characteristics of one-dimensional disordered systems are examined using the Fokkerr-Planck equations developed earlier in the text. Also includes a description of the general structure of concentration expansions, giving examples of simple applications.

An introductory book on the statistical mechanics of disordered systems, ideal for graduates and researchers.

Publisher Description

Disordered systems are statistical mechanics models in random environments. This lecture notes volume concerns the equilibrium properties of a few carefully chosen examples of disordered Ising models. The approach is that of probability theory and mathematical physics, but the subject matter is of interest also to condensed matter physicists, material scientists, applied mathematicians and theoretical computer scientists. (The two main types of systems considered are disordered ferromagnets and spin glasses. The emphasis is on questions concerning the number of ground states (at zero temperature) or the number of pure Gibbs states (at nonzero temperature). A recurring theme is that these questions are connected to interesting issues concerning percolation and related models of geometric/combinatorial probability. One question treated at length concerns the low temperature behavior of short-range spin glasses: whether and in what sense Parisi's analysis of the meanfield (or "infinite-range") model is relevant. Closely related is the more general conceptual issue of how to approach the thermodynamic (i.e., infinite volume) limit in systems which may have many complex competing states. This issue has been addressed in recent joint work by the author and Dan Stein and the book provides a mathematically coherent presentation of their approach.)

Fractals and disordered systems have recently become the focus of intense interest in research. This book discusses in great detail the effects of disorder on mesoscopic scales (fractures, aggregates, colloids, surfaces and interfaces, glasses and polymers) and presents tools to describe them in mathematical language. A substantial part is devoted to the development of scaling theories based on fractal concepts. In ten chapters written by leading experts in the field, the reader is introduced to basic concepts and techniques in disordered systems and is led to the forefront of current research. This second edition has been substantially revised and updates the literature in this important field.

Originally published in 1979, this book discusses how the physical and chemical properties of disordered systems such as liquids, glasses, alloys, amorphous semiconductors, polymer solutions and magnetic materials can be explained by theories based on a variety of mathematical models, including random assemblies of hard spheres, tetrahedrally-bonded networks and lattices of 'spins'. The text describes these models and the various mathematical theories by which the observable properties are derived. Techniques and concepts such as the mean field and coherent approximations, graphical summation, percolation, scaling and the renormalisation group are explained and applied. This book will be of value to anyone with an interest in theoretical and experimental physics.

A self-contained, mathematical introduction to the driving ideas in equilibrium statistical mechanics, studying important models in detail.