This book focuses on one mechanism in black hole physics which has proven to be universal, multifaceted and with a rich phenomenology: rotational superradiance. This is an energy extraction process, whereby black holes can deposit their rotational energy in their surroundings, leading to Penrose processes, black-hole bombs, and even Hawking radiation. Black holes are key players in star formation mechanisms and as engines to some of the most violent events in our universe. Their simplicity and compactness make them perfect laboratories, ideally suited to probe new fields or modifications to the theory of gravity. Thus, black holes can also be used to probe some of the most important open problems in physics, including the nature of dark matter or the strong CP problem in particle physics. This monograph is directed to researchers and graduate students and provides a unified view of the subject, covering the theoretical machinery, experimental efforts in the laboratory, and astrophysics searches. It is focused on recent developments and works out a number of novel examples and applications, ranging from fundamental physics to astrophysics. Non-specialists with a scientific background should also find this text a valuable resource for understanding the critical issues of contemporary research in black-hole physics. This second edition stresses the role of ergoregions in superradiance, and completes its catalogue of energy-extraction processes. It presents a unified description of instabilities of spinning black holes in the presence of massive fields. Finally, it covers the first experimental observation of superradiance, and reviews the state-of-the-art in the searches for new light fields in the universe using superradiance as a mechanism.

Super-radiance: Multiatomic Coherent Emission provides a comprehensive, self-contained account of the theory and experiments of the quantum optic phenomenon of superradiance. Contributed by highly regarded researchers in the field, the book first presents the theory of superradiance at a level suitable for graduate physicists approaching the subject for the first time. This introduction is followed by a more rigorous treatment that is supported by the analysis of experiments dealing with superradiance and by a discussion on the possible uses of the effect in other areas of optics and electronics. The theoretical and experimental results presented in this book will introduce a wide audience to this important area of quantum optics.

Super-radiance: Multiatomic Coherent Emission provides a comprehensive, self-contained account of the theory and experiments of the quantum optic phenomenon of superradiance. Contributed by highly regarded researchers in the field, the book first presents the theory of superradiance at a level suitable for graduate physicists approaching the subject for the first time. This introduction is followed by a more rigorous treatment that is supported by the analysis of experiments dealing with superradiance and by a discussion on the possible uses of the effect in other areas of optics and electronics. The theoretical and experimental results presented in this book will introduce a wide audience to this important area of quantum optics.

Cooperative Effects in Optics: Superradiance and Phase Transitions presents a systematic treatment of the modern theory of cooperative optical phenomena-processes in which the behavior of many-body systems of radiators or absorbers is essentially determined by their collective interactions with each other. The book focuses on the theory of collective spontaneous radiation (superradiance) and provides a detailed physical explanation of the mechanism of collective spontaneous emission. It considers numerous models of novel nonequilibrium light-induced phase transitions in a typical quantum electronics system, including two-level atoms interacting with the radiation field and more complex systems of three-level atoms, two-bank semiconductors, and other interatomic interactions with the electrostatic and lattice displacement fields. The book uses some of these models for the interpretation of experimentally observed light-induced critical phenomena. Cooperative Effects in Optics is of great value to research workers in the field of cooperative optical phenomena, especially in the determination of the physical essence of theoretical models developed to describe cooperative effects in multi-atomic systems.

"Wald's book is clearly the first textbook on general relativity with a totally modern point of view; and it succeeds very well where others are only partially successful. The book includes full discussions of many problems of current interest which are not treated in any extant book, and all these matters are considered with perception and understanding."—S. Chandrasekhar "A tour de force: lucid, straightforward, mathematically rigorous, exacting in the analysis of the theory in its physical aspect."—L. P. Hughston, Times Higher Education Supplement "Truly excellent. . . . A sophisticated text of manageable size that will probably be read by every student of relativity, astrophysics, and field theory for years to come."—James W. York, Physics Today

The Compound-Nuclear Reaction and Related Topics (CNR*) international workshop series was initiated in 2007 with a meeting near Yosemite National Park. It has since been held in Bordeaux (2009), Prague (2011), Sao Paulo (2013), Tokyo (2015), and Berkeley, California (2018). The workshop series brings together experts in nuclear theory, experiment, data evaluations, and applications, and fosters interactions among these groups. Topics of interest include: nuclear reaction mechanisms, optical model, direct reactions and the compound nucleus, pre-equilibrium reactions, fusion and fission, cross section measurements (direct and indirect methods), Hauser-Feshbach theory (limits and extensions), compound-nuclear decays, particle and gamma emission, level densities, strength functions, nuclear structure for compound-nuclear reactions, nuclear energy, nuclear astrophysics, and other topics. This peer-reviewed proceedings volume presents papers and poster summaries from the 6th International Workshop on Compound-Nuclear Reactions and Related Topics CNR*18, held on September 24-28, 2018, at Lawrence Berkeley National Lab, Berkeley, CA.

This volume gives a unified picture of the multifaceted subject of superradiance, with a focus on recent developments in the field, ranging from fundamental physics to astrophysics. Superradiance is a radiation enhancement process that involves dissipative systems. With a 60 year-old history, superradiance has played a prominent role in optics, quantum mechanics and especially in relativity and astrophysics. In Einstein's General Relativity, black-hole superradiance is permitted by dissipation at the event horizon, which allows energy extraction from the vacuum, even at the classical level. When confined, this amplified radiation can give rise to strong instabilities known as "blackhole bombs'', which have applications in searches for dark matter, in physics beyond the Standard Model and in analog models of gravity. This book discusses and draws together all these fascinating aspects of superradiance.