Theory Of Quantum Fluids

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.

Theory of Quantum Fluids is a concise report on the microscopic description of liquid 4He and liquid 3He in the physical density range using simple forms of the potential function between pairs of neutral atoms and the properties of the ground states and limited ranges of low excited states. The monograph covers the properties of the radial distribution function and the three-particle distribution particle; the classical sound field and the correspondence principle; paired phonon states in the free- phonon approximation; the uniform limit and the charged boson system; and the microscopic theory of a single 3He atom in the 4He liquid. Theoretical and experimental physicists will find the book very interesting.

The aim of this primer is to cover the essential theoretical information, quickly and concisely, in order to enable senior undergraduate and beginning graduate students to tackle projects in topical research areas of quantum fluids, for example, solitons, vortices and collective modes. The selection of the material, both regarding the content and level of presentation, draws on the authors analysis of the success of relevant research projects with newcomers to the field, as well as of the students feedback from many taught and self-study courses on the subject matter. Starting with a brief historical overview, this text covers particle statistics, weakly interacting condensates and their dynamics and finally superfluid helium and quantum turbulence. At the end of each chapter (apart from the first) there are some exercises. Detailed solutions can be made available to instructors upon request to the authors.

The second International Symposium on Quantum Fluids and Solids came to pass during 23-27 Jan. 1977 as the fourth and con cluding part of the seventeenth consecutive running of the Sanibel Symposium Series. With approximately 120 participants from eleven countries (including, for the first time, the USSR), we found it easy to obtain a selection of papers which was fairly comprehen sive. Indeed, our problem was an embarrassment of riches; in spite of our solemn vows not to crowd the schedule, we ended up with an intense program! By far, the majority of the papers pre sented are represented in this volume. We are indebted to many persons and organizations for their contributions to the Symposia. First, we thank Prof. Per-Olov Lowdin, Director of the Quantum Theory Project and originator of the Sanibel Symposia. Without his patient, indulgent cooperation our task would have been vastly more difficult. We are grateful to Prof. F. Eugene Dunnam, Chairman of the Dept. of Physics and Astronomy, for providing Departmental support of our initial or ganlzlng expenses. Approximately one-half of the total cost of the Symposium was borne by a joint grant from the National Science Foundation and the U. S. Air Force Office of Scientific Research. We thank the program officers, Dr. C. Satterthwaite and Dr. D.

Superconductivity and Quantum Fluids, Volume 29 presents the microscopic theory of superconductivity and superfluidity. This book discusses the characteristics of niobium, which is a type II superconductor. Organized into two parts encompassing eight chapters, this volume begins with an overview of the special Bogoliubov transformation that connects fermions with opposite spins and momenta. This text then describes the collective oscillations of the system in the cases of charged and uncharged particles. Other chapters consider the dynamical system of Fermi particles in a weak external field. This book discusses as well the theoretical explanation of superfluidity, which is as a second, very interesting phenomenon observed at low temperatures. The final chapter illustrates the linearized hydrodynamic equations and explains the mean value expressed in terms of the Fourier components of the retarded Green functions. This book is a valuable resource for physicists. Students and researchers who are interested in the fields of superconductivity and superfluidity will also find this book useful.

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.

"Originally published as two separate volumes, The Theory of Quantum Liquids is a classic text that attempts to describe the qualitative and unifying aspects of an extremely broad and diversified field"

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.