Black Holes, Cosmology And Extra Dimensions (Second Edition)


Book Description

Assuming basic knowledge of special and general relativity, this book guides the reader to problems under consideration in modern research, concerning black holes, wormholes, cosmology, and extra dimensions. Its first part is devoted to local strong field configurations (black holes and wormholes) in general relativity and its most relevant extensions: scalar-tensor, f(R), and multidimensional theories. The second part discusses cosmology, including inflation and problems of a unified description of the whole evolution of the universe. The third part concerns multidimensional theories of gravity and contains a number of original results obtained by the authors. Expository work is conducted for a mechanism of symmetries and fundamental constants formation. The original approach to nonlinear multidimensional gravity that is able to construct a unique perspective describing different phenomena is highlighted.Much of the content was previously presented only in journal publications and is new for book contents, e.g., on regular black holes, various scalar field solutions, wormholes and their stability, inflation, clusters of primordial black holes, and multidimensional gravity. The last two topics are added in this new edition of the book. The other chapters are also updated to include new discoveries like the detection of gravitational waves.




Regular Black Holes


Book Description

Black holes are one of the most fascinating predictions of general relativity. They are the natural product of the complete gravitational collapse of matter and today we have a body of observational evidence supporting the existence of black holes in the Universe. However, general relativity predicts that at the center of black holes there are spacetime singularities, where predictability is lost and standard physics breaks down. It is widely believed that spacetime singularities are a symptom of the limitations of general relativity and must be solved within a theory of quantum gravity. Since we do not have yet any mature and reliable candidate for a quantum gravity theory, researchers have studied toy-models of singularity-free black holes and of singularity-free gravitational collapses in order to explore possible implications of the yet unknown theory of quantum gravity. This book reviews all main models of regular black holes and non-singular gravitational collapses proposed in the literature, and discuss the theoretical and observational implications of these scenarios.




Three Lectures on Complexity and Black Holes


Book Description

These three lectures cover a certain aspect of complexity and black holes, namely the relation to the second law of thermodynamics. The first lecture describes the meaning of quantum complexity, the analogy between entropy and complexity, and the second law of complexity. Lecture two reviews the connection between the second law of complexity and the interior of black holes. Prof. L. Susskind discusses how firewalls are related to periods of non-increasing complexity which typically only occur after an exponentially long time. The final lecture is about the thermodynamics of complexity, and “uncomplexity” as a resource for doing computational work. The author explains the remarkable power of “one clean qubit,” in both computational terms and in space-time terms. This book is intended for graduate students and researchers who want to take the first steps towards the mysteries of black holes and their complexity.




Beyond Einstein Gravity


Book Description

Beyond Einstein’s Gravity is a graduate level introduction to extended theories of gravity and cosmology, including variational principles, the weak-field limit, gravitational waves, mathematical tools, exact solutions, as well as cosmological and astrophysical applications. The book provides a critical overview of the research in this area and unifies the existing literature using a consistent notation. Although the results apply in principle to all alternative gravities, a special emphasis is on scalar-tensor and f(R) theories. They were studied by theoretical physicists from early on, and in the 1980s they appeared in attempts to renormalize General Relativity and in models of the early universe. Recently, these theories have seen a new lease of life, in both their metric and metric-affine versions, as models of the present acceleration of the universe without introducing the mysterious and exotic dark energy. The dark matter problem can also be addressed in extended gravity. These applications are contributing to a deeper understanding of the gravitational interaction from both the theoretical and the experimental point of view. An extensive bibliography guides the reader into more detailed literature on particular topics.




Dynamics of Extremal Black Holes


Book Description

This Brief presents in a self-contained, non-technical and illustrative fashion the state-of-the-art results and techniques for the dynamics of extremal black holes. Extremal black holes are, roughly speaking, either maximally rotating or maximally charged. Astronomical observations suggest that near-extremal (stellar or supermassive) black holes are ubiquitous in the universe. The book presents various recently discovered characteristic phenomena (such as the horizon instability) that have enhanced our understanding of the dynamics of extremal black holes. The topics should be of interest to pure mathematicians, theoretical physicists and astronomers. This book provides common ground for communication between these scientific communities.




What Is Inside a Black Hole?


Book Description

'If you feel you are in a black hole, don't give up. There's a way out' What is inside a black hole? Is time travel possible? Throughout his extraordinary career, Stephen Hawking expanded our understanding of the universe and unravelled some of its greatest mysteries. In What Is Inside a Black Hole? Hawking takes us on a journey to the outer reaches of our imaginations, exploring the science of time travel and black holes. 'The best most mind-bending sort of physics' The Times Brief Answers, Big Questions: this stunning paperback series offers electrifying essays from one of the greatest minds of our age, taken from the original text of the No. 1 bestselling Brief Answers to the Big Questions.




Black Holes in the Era of Gravitational-Wave Astronomy


Book Description

Black Holes in the Era of Gravitational-Wave Astronomy provides a multidisciplinary, up-to-date view of the physics of black holes, along with an exhaustive overview of crucial open questions and recent advancements in the astrophysics of black holes in the wake of incredible advancements made in the last decade. It includes discussions on improvements in theoretical modeling and observational perspectives for black holes of all sizes, along with associated challenges. The book's structure and themes will enable an entwined understanding of black hole physics at all scales, thus avoiding the compartmentalized view that is typical of more specialized manuscripts and reviews.This book is a complete reference for scientists interested in a multidirectional approach to the study of black holes. It provides substantial discussions about the interplay of different types of black holes and gives professionals a heterogeneous and comprehensive overview of the astrophysics of black holes of all masses. Focuses on recent advances and future perspectives surrounding black holes, providing researchers with a clear view of cutting-edge research Offers readers a multidisciplinary, fresh view on black holes, discussing and reviewing the most recent advancements in theoretical, numerical and observational techniques put in place to detect black holes Provides a bridge among different black hole areas, fostering new collaborations among professionals working in different, but intrinsically interconnected fields




General Relativity


Book Description

Written for advanced undergraduate and graduate students, this is a clear mathematical introduction to Einstein's theory of general relativity and its physical applications. Concentrating on the theory's physical consequences, this approachable textbook contains over 300 exercises to illuminate and extend the discussion.




Black Holes


Book Description

The legendary physicist explores his favorite subject in a pair of enlightening, accessible, and cleverly illustrated essays for curious readers, originally delivered as BBC lectures. “It is said that fact is sometimes stranger than fiction, and nowhere is that more true than in the case of black holes. Black holes are stranger than anything dreamed up by science-fiction writers, but they are firmly matters of science fact.” For decades, Stephen Hawking has been fascinated by black holes. He believes that if we understood the challenges they pose to the very nature of space and time, we could unlock the secrets of the universe. In these conversational pieces, Hawking’s sense of wonder is infectious as he holds forth on what we know about black holes, what we still don’t know, and theoretical answers to more specific questions, such as: What would happen if you ever got sucked into one? Annotated and with an introduction by BBC News science editor David Shukman, featuring whimsical and illuminating illustrations, Black Holes offers a candid peek into one of the great scientific mysteries of all time. Praise for Stephen Hawking “[Hawking] can explain the complexities of cosmological physics with an engaging combination of clarity and wit. . . . His is a brain of extraordinary power.”—The New York Review of Books “Hawking clearly possesses a natural teacher’s gifts—easy, good-natured humor and an ability to illustrate highly complex propositions with analogies plucked from daily life.”—The New York Times “A high priest of physics, one of a handful of theorists who may be on the verge of reading God’s mind.”—Los Angeles Times




Quasi-normal Modes of Black Holes


Book Description

The detection of gravitational waves has ushered in a new era in physics called black hole spectroscopy. Black holes are predicted by General Relativity to be simple objects of nature, describable completely by their mass, angular momentum, and electric charge, thus satisfying the no-hair theorem. When black holes coalesce, they emit a particular kind of gravitational radiation waveform which includes a phase of quasi-normal modes (QNMs) during the ringdown stage, which decay with time. If the no-hair theorem of Einstein's theory of gravity holds, these modes and their frequencies are completely specified by the mass, angular momentum, and charge of the final black hole. QNMs can be used to test the no-hair theorem. Further, since General Relativity and specific modified theories of gravity differ in their predictions of QNMs, observation of such gravitational waves can be used to test theories of gravitation. This thesis aims to introduce the concepts necessary to the reader to understand the emerging field of black hole spectroscopy by focusing on black holes and their QNMs. In this thesis linearized gravity in General Relativity, the QNMs of Schwarzschild and Kerr black holes, no hair-hair theorems, and alternative theories of gravitation are presented. A modified theory of gravity, Einstein-dilaton Gauss-Bonnet Gravity, motivated by string theoretic attempts to combine General Relativity and quantum mechanics for a theory of quantum gravity, is presented, and QNMs for the theory are presented and discussed.