Over the last decade the physics of black holes has been revolutionized by developments that grew out of Jacob Bekenstein's realization that black holes have entropy. Stephen Hawking raised profound issues concerning the loss of information in black hole evaporation and the consistency of quantum mechanics in a world with gravity. For two decades these questions puzzled theoretical physicists and eventually led to a revolution in the way we think about space, time, matter and information. This revolution has culminated in a remarkable principle called "The Holographic Principle", which is now a major focus of attention in gravitational research, quantum field theory and elementary particle physics. Leonard Susskind, one of the co-inventors of the Holographic Principle as well as one of the founders of String theory, develops and explains these concepts.

Delirium is a cognitive disorder consisting of deficits of attention, arousal, consciousness, memory, orientation, perception, speech and language. It represents the most frequent complication of hospitalisation in the older population. Despite its importance in terms of clinical, economic and social considerations, and despite considerable advances in the past decade, it remains a relatively misunderstood and mis-diagnosed condition.

This book provides a state-of-the-art update of delirium research, covering its history, conceptualisation, measurement, epidemiology, pathophysiology, assessment, diagnosis, causes, prevention and management. The final chapter takes a look to the future, highlighting the importance of ongoing interdisciplinary research.

As well as being important as a clinical syndrome in its own right, the study of delirium provides a valuable opportunity to understand brain functioning at a fundamental level, and as it is a preventable condition, it is also now being used as a marker to measure the quality of hospital care provided for older people.

This volume will serve as a catalyst to revive interest and progress in delirium research and clinical care, and should be read by psychiatrists, neurologists, geriatricians and all those involved in working with the elderly in hospitals or in the community.

Over the last decade the physics of black holes has been revolutionized by developments that grew out of Jacob Bekenstein's realization that black holes have entropy. Stephen Hawking raised profound issues concerning the loss of information in black hole evaporation and the consistency of quantum mechanics in a world with gravity. For two decades these questions puzzled theoretical physicists and eventually led to a revolution in the way we think about space, time, matter and information. This revolution has culminated in a remarkable principle called "The Holographic Principle", which is now a major focus of attention in gravitational research, quantum field theory and elementary particle physics. Leonard Susskind, one of the co-inventors of the Holographic Principle as well as one of the founders of String theory, develops and explains these concepts.

Exploring how the subtleties of quantum coherence can be consistently incorporated into Einstein's theory of gravitation, this book is ideal for researchers interested in the foundations of relativity and quantum physics. The book examines those properties of coherent gravitating systems that are most closely connected to experimental observations. Examples of consistent co-gravitating quantum systems whose overall effects upon the geometry are independent of the coherence state of each constituent are provided, and the properties of the trapping regions of non-singular black objects, black holes and a dynamic de Sitter cosmology are discussed analytically, numerically and diagrammatically. The extensive use of diagrams to summarise the results of the mathematics enables readers to bypass the need for a detailed understanding of the steps involved. Assuming some knowledge of quantum physics and relativity, the book provides text boxes featuring supplementary information for readers particularly interested in the philosophy and foundations of the physics.