The 1982 Antwerp Advanced Study Institute on "Physics of Polarons and Excitons in Polar Semiconductors and Ionic Crystals" took place from July 26 till August 5 at the Conference Center Priorij Corsen- donk, a restored monastery, close to the city of Antwerp. It was the seventh Institute in our series which started in 1971. This Advanced Study Institute, which was held fifty years after Landau introduced the polaron concept, can be considered as the third major international symposium devoted to the physics of pola- rons. The first such symposium took place in St. Andrews in 1962 under the...

The borderline of quantum electrodynamics and quantum optics offer spectacular results and problems concerning the foundations of radiation theory. Perhaps the major new viewpoint that has emerged from recent investigations is that one can now work inside a time-dependent quantum process, whereas up to now all elementary quantum processes were either stationary, or one worked with asymptotic in-and out-states, i.e. an S-matrix approach. In the-rirst part of this volume, the Quantum Electrodynamics, the present status of the main approaches to this most accurate of all physical theories are...

The Advanced Study Institute on Strongly Coupled Plasmas was held on the campus of the Universite d'Orleans, Orleans-la-Source, France, from July 6th through July 23rd, 1977. 15 invited lecturers and 50 other participants attended the Institute. The present Volume contains the texts of most of the lectures and of some of the numerous seminars presented at the Institute. The topic of strongly coupled coulomb-systems has been an area of vigorous activities over the last few years. Such systems occur in a great variety of physical situations: stellar and planetary interiors, solid and liquid...

That man is a social being is almost axiomatic. Our interpersonal relation ships can be sources of the most rewarding or the most painful of human experiences. To a large measure our accomplishments in life depend on the facility with which we interact with others-our social skill. The acquisition of social skills is, of course, a natural part of the overall socialization process. However, in many instances it becomes necessary or desirable to develop further an individual's social facilities. Such skill development is the topic of this book. Two major goals were kept in mind in the writing...

This volume contains the proceedings of a two-week NATO A.S.I. on Integrated Optics: Physics and Applications, held from August 17 to August 30, 1981 in Erice, Italy. This is the 8th annual Course of the "International School of Quantum Electronics" presented under the auspices of the "E. Majorana" Centre for Scientific Culture. The subject was chosen in order to satisfy the demand for a course on integrated optics which is relevant to the expanding use of fiber optics for communication and signal processing. Integrated Optics, encompassing all of the optical waveguide circuits which are the...

The present volume contains contributions presented at the NATO Advanced Study Institute on Molecular Ions held on the island of Kos, Greece, from September 30 to October 10, 1980. The meeting was attended by some 60 participants from 15 different countries. It was the first meeting devoted exclusively to the topic of molecular ions. Its vitality derived from bringing together experts and students from a wide variety of disciplines, whose studies bear upon the structure of molecular ions. The aim of the meeting was to assemble these scientists, representing many countries in Europe and North...

The 1976 Cargese Summer Institute was devoted to the study of certain exciting developments in quantum field theory and critical phenomena. Its genesis occurred in 1974 as an outgrowth of many scientific discussions amongst the undersigned, who decided to form a scientific committee for the organization of the school. On the one hand, various workers in quantum field theory were continuing to make startling progress in different directions. On the other hand, many new problems were arising from these various domains. Thus we feIt that 1976 might be an appropriate occasion both to review...

The importance of real space imaging and spatially-resolved spectroscopy in many of the most significant problems of surface and interface behaviour is almost self evident. To join the expertise of the tradi tional surface scientist with that of the electron microscopist has however been a slow and difficult process. In the past few years remarkable progress has been achieved, including the development of new techniques of scanning transmission and reflection imaging as well as low energy microscopy, all carried out in greatly improved vacuum conditions. Most astonishing of all has been the...

The interest of describing the ground state properties of a system in terms of one electron density (or its two spin components) is obvious, in particular due to the simple physical significance of this function. Recent experimental progress in diffraction made the measurement of charge and magnetization densities in crystalline solids possible, with an accuracy at least as good as theoretical accuracy. Theoretical developments of the many-body problem have proved the extreme importance of the one electron density function and presently, accurate methods of band structure determination become...