A concise introduction to statistical mechanics for physicists, this volume will prove of particular interest to students and professionals concerned with any branch of solid state physics or low temperature physics. It offers a clear and simple presentation of the principles of statistical mechanics, with examples that illustrate generalities and issues of critical interest to physicists.The text outlines the application of Bose-Einstein statistics to the liquid helium question, and discussions of problems include models for vibration in solids, electrical resistivity, and the statistical mechanics of free electrons in metals (Fermi-Dirac statistics). Physical essentials are supplemented by more detailed analysis in the appendices. Special features include extensive consideration of significant physical problems and discussion and analysis of the influence of anharmonicity of lattice vibrations. In addition, an outline of important questions covers issues of irreversibility in physics.