Bose-Einstein condensation of excitons is a unique effect in which the electronic states of a solid can self-organize to acquire quantum phase coherence. The phenomenon is closely linked to Bose-Einstein condensation in other systems such as liquid helium and laser-cooled atomic gases. Covering theoretical aspects as well as recent experimental work, the book provides a comprehensive survey of the field. After introducing the relevant basic physics of excitons, the authors discuss exciton-phonon interactions as well as the behavior of biexcitons. They also cover exciton phase-transitions and give particular attention to nonlinear optical effects including the optical Stark effect and chaos in excitonic systems. The thermodynamics of equilibrium, quasiequilibrium, and nonequilibrium systems are examined in detail. Throughout, the authors interweave theoretical and experimental results. The book will be of great interest to graduate students and researchers in semiconductor and superconductor physics, quantum optics, and atomic physics.

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.)

This volume contains the best lectures from the Summer School Lectures volumes dealing with the theme of pattern formation. Topics include self-organization by simulated evolution, nonlinear dynamics of pattern formation in physics and biology, and the emergence of computational ecologies.

1) Phase Transitions, represented by generalizations of the classical Stefan problem. This is studied by Kenmochi and Rodrigues by means of variational techniques.
2) Hysteresis Phenomena. Some alloys exhibit shape memory effects, corresponding to a stress-strain relation which strongly depends on temperature; mathematical physical aspects are treated in M ller's paper. In a general framework, hysteresis can be described by means of hysteresis operators in Banach spaces of time dependent functions; their properties are studied by Brokate.
3) Numerical analysis. Several models of the phenomena above can be formulated in terms of nonlinear parabolic equations. Here Verdi deals with the most updated approximation techniques.

Currently much research is being undertaken, within a wide range of scientific and engineering disciplines, on macroscopic phenomena associated with liquid boundaries. This volume contains articles which address the modelling of such phenomena from a variety of viewpoints. These works serve to acquaint the reader with the range of macroscopic behaviour which can occur at liquid boundaries, to indicate various aproaches to relevant continuum descriptions and the difficulties of modelling non-equilibrium situations, to demonstrate applications of continuum models to the solution of practical problems, and to convey due appreciation of experimental aspects of the subject. The specific topics addressed are phenomenological approaches to fluid-flute interfaces and the physical interpretation of associated concepts and quantities, non-equilibrium thermodynamics and statistical physics of liquid-vapour interfaces, the physics of ice-water phase-change surfaces, and the prediction of static and dynamic contact angles, wetting and spreading.

Internationally recognized experts in the field of holographic interferometric testing, X-ray testing, and structural analysis by finite element techniques have come together in ESPRIT project 898 to develop a system that integrates these techniques. This system acts as an external interface between the complementary nondestructive testing methods and computer based structural analysis. In the book the testing and analysis techniques are presented and compared with special emphasis on problems regarding their combination and integration. The architecture and the components of the interface system are described. Experiments proving the feasibility and applicability of the concepts are presented. The chapters of the book dealing with the different techniques are written by the individual partners of the project. A common test object is investigated by all techniques. The book helps the customer to select the testing and analysis method most suitable for his problem. It also presents the background for building up integrated testing equipment for analysis and control.

Die dritte Auflage der Elektroakustik wurde in Symbolik und Nomenklatur an moderne Schreibweisen angepasst und enthalt neue Abschnitte zu DIN-Normen und VDI-Richtlinien. Der Besprechung von Schallabstrahlung, -brechung, -beugung, -absorption und -transmission wurde ein eigener Abschnitt gewidmet, die Berechnung der Schallgeschwindigkeit wurde ausfuhrlicher dargestellt, und man findet etwas zu Compact Disk und Digital Audio Tape-Recorder. Zahlreiche durchgerechnete Beispiele helfen bei der Aneignung des Stoffes. Der Praktiker wird auch das englische Stichwortverzeichnis begrussen."

The "Seventh International Symposium on the Photochemistry and Photo- physics of Coordination Compounds" was held in the charming Schlo~ Elmau lying in a hidden valley of the Bavarian Alps above Garmisch- Partenkirchen, Federal Republic of Germany, from March 29 to April 2, 1987. About ninety participants from seventeen countries including about thirty non-European scientists as far away as Japan and Australia came together for this symposium. Forty-five oral and twenty-five poster contributions were presented. These presentations and the opportunity for many formal and informal discussions stimulated an intense scienti- fic interaction between the participants. This meeting followed previous symposia held in Muhlheim 1974 (Koerner von Gustorf), Ferrara 1976 (Carassiti, Scandola), Koln 1978 (Wasgestian), Montreal 1980 (Serpone), Paris 1982 (Gianotti) and London 1984 (Harriman). The main fields covered by this 7th Symposium were photo-redox processes, organometallic photochemistry, and properties of metal centered excited states. Furthermore, special complexes such as 2+ [Ru(bpy)3] and related compounds as well as Cr(III)-complexes were discussed extensively. Moreover, a series of potential applications such as solar energy conversion and storage (e.g. water splitting) and photoresist technology were important subjects of this meeting. Thus, it was shown again that the rapidly expanding field of excited-state chemistry and physics of coordination compounds has become an important part of inorganic chemistry.

This book contains the papers presented at the "First International Sympo st sium on Aerogels (1 ISA)," held in September 1985 at. the University of Wiirzburg, Fed. Rep. of Germany. It was the first meet.ing of this kind, wit.h participants from several European count.ries, the United States of America, Canada, South America, and Africa. The meeting was interdisciplinary, with most of the participants being physicists, chemists or material scientists ei ther from universities or from industrial research institutes. Let me try to shed some light upon the class of substances the symposium was about: Aerogels are extremely porous high-tech materials, consisting ei ther of silica, alumina, zirconia, stannic or tungsten oxide or mixtures of these oxides. Due to their high porosity (up t.o 99% ) and t.heir large inner surface, aerogels serve as especially active catalysts or as catalytic subst.rates, as adsorbents, fillers, reinforcement agents, pigments and gellifying agents. Silica aerogels as translucent or transparent superinsulating fillers in window systems could help to considerably reduce thermal losses in windows and to improve the energy balance in passive solar systems. Aerogels also have fas cinating acoustic properties - the sound velocity can be as low as 100 m/s The production of aerogels starts with the controlled conversion of a sol into a gel: The growth of clusters or polymer chains from a chemical solution, the cross-linking of these primary entities and the formation of a coherent network - still embedded in a liquid."

Organized by Tata Institute of Fundamental Research, Bombay

Epitaxial growth and electronic properties of semiconductor thin films are becoming increasingly important for fundamental and applied research and for device applications. This book contains a comprehensive collection of over 1500 references covering the first 25 years of molecular beam epitaxy of III-V compound semiconductors. Molecular beam epitaxy is a versatile thin film growth technique which emerged from the 'Three-temperature method' de veloped in the 1950s and from surface kinetic studies performed in the 1960s. III-V semiconductors such as GaAs, AlAs, (Galn)As, InP, etc., play an important role in the application to optoelectronic and high-speed devices. Over the past three years the technology of molecular beam epitaxy has spread rapidly to most major research and development laboratories through out the world, and an increasing number of highly refined III-V semiconduc tor structures with exactly tailored electronic properties have been pro duced and explored for fundamental studies as well as for device appl ica tion. The comprehensive bibliography on this dramatically expanding topic helps chemists, engineers, materials scientists, and physicists working in semiconductor research and development areas to sort out the important lit erature of their particular interest. A direct reproduction of the output of a computer printer has been used to enable rapid publication and to keep printing costs low. The work was sponsored by the 'Bundesministerium fUr Forschung und Technologie' of the Federal Republic of Germany. Stuttgart, January 1984 K. Ploog . K. Graf Subject Categories and References Introduction . . . . . . . . . . . . . . . . . . . Year 1977 . . . . . . . . . . . . . . . . . . . . ."