Black Holes, Gravitational Radiation and the Universe


Book Description

Our esteemed colleague C. V. Vishveshwara, popularly known as Vishu, turned sixty on 6th March 1998. His colleagues and well wishers felt that it would be appropriate to celebrate the occasion by bringing out a volume in his honour. Those of us who have had the good fortune to know Vishu, know that he is unique, in a class by himself. Having been given the privilege to be the volume's editors, we felt that we should attempt something different in this endeavour. Vishu is one of the well known relativists from India whose pioneer ing contributions to the studies of black holes is universally recognised. He was a student of Charles Misner. His Ph. D. thesis on the stability of the Schwarzschild black hole, coordinate invariant characterisation of the sta tionary limit and event horizon for Kerr black holes and subsequent seminal work on quasi-normal modes of black holes have passed on to become the starting points for detailed mathematical investigations on the nature of black holes. He later worked on other aspects related to black holes and compact objects. Many of these topics have matured over the last thirty years. New facets have also developed and become current areas of vigorous research interest. No longer are black holes, ultracompact objects or event horizons mere idealisations of mathematical physicists but concrete entities that astrophysicists detect, measure and look for. Astrophysical evidence is mounting up steadily for black holes.




Gravitational Radiation, Luminous Black Holes and Gamma-Ray Burst Supernovae


Book Description

Black holes and gravitational radiation are two of the most dramatic predictions of general relativity. The quest for rotating black holes - discovered by Roy P. Kerr as exact solutions to the Einstein equations - is one of the most exciting challenges facing physicists and astronomers. Gravitational Radiation, Luminous Black Holes and Gamma-Ray Burst Supernovae takes the reader through the theory of gravitational radiation and rotating black holes, and the phenomenology of GRB-supernovae. Topics covered include Kerr black holes and the frame-dragging of spacetime, luminous black holes, compact tori around black holes, and black-hole spin interactions. It concludes with a discussion of prospects for gravitational-wave detections of a long-duration burst in gravitational-waves as a method of choice for identifying Kerr black holes in the Universe. This book is ideal for a special topics graduate course on gravitational-wave astronomy and as an introduction to those interested in this contemporary development in physics.




The Little Book of Black Holes


Book Description

Dive into a mind-bending exploration of the physics of black holes Black holes, predicted by Albert Einstein’s general theory of relativity more than a century ago, have long intrigued scientists and the public with their bizarre and fantastical properties. Although Einstein understood that black holes were mathematical solutions to his equations, he never accepted their physical reality—a viewpoint many shared. This all changed in the 1960s and 1970s, when a deeper conceptual understanding of black holes developed just as new observations revealed the existence of quasars and X-ray binary star systems, whose mysterious properties could be explained by the presence of black holes. Black holes have since been the subject of intense research—and the physics governing how they behave and affect their surroundings is stranger and more mind-bending than any fiction. After introducing the basics of the special and general theories of relativity, this book describes black holes both as astrophysical objects and theoretical “laboratories” in which physicists can test their understanding of gravitational, quantum, and thermal physics. From Schwarzschild black holes to rotating and colliding black holes, and from gravitational radiation to Hawking radiation and information loss, Steven Gubser and Frans Pretorius use creative thought experiments and analogies to explain their subject accessibly. They also describe the decades-long quest to observe the universe in gravitational waves, which recently resulted in the LIGO observatories’ detection of the distinctive gravitational wave “chirp” of two colliding black holes—the first direct observation of black holes’ existence. The Little Book of Black Holes takes readers deep into the mysterious heart of the subject, offering rare clarity of insight into the physics that makes black holes simple yet destructive manifestations of geometric destiny.




Black Holes, Gravitational Radiation and the Universe


Book Description

Our esteemed colleague C. V. Vishveshwara, popularly known as Vishu, turned sixty on 6th March 1998. His colleagues and well wishers felt that it would be appropriate to celebrate the occasion by bringing out a volume in his honour. Those of us who have had the good fortune to know Vishu, know that he is unique, in a class by himself. Having been given the privilege to be the volume's editors, we felt that we should attempt something different in this endeavour. Vishu is one of the well known relativists from India whose pioneer ing contributions to the studies of black holes is universally recognised. He was a student of Charles Misner. His Ph. D. thesis on the stability of the Schwarzschild black hole, coordinate invariant characterisation of the sta tionary limit and event horizon for Kerr black holes and subsequent seminal work on quasi-normal modes of black holes have passed on to become the starting points for detailed mathematical investigations on the nature of black holes. He later worked on other aspects related to black holes and compact objects. Many of these topics have matured over the last thirty years. New facets have also developed and become current areas of vigorous research interest. No longer are black holes, ultracompact objects or event horizons mere idealisations of mathematical physicists but concrete entities that astrophysicists detect, measure and look for. Astrophysical evidence is mounting up steadily for black holes.




Gravitational Waves


Book Description

On 14 September 2015, after 50 years of searching, gravitational waves were detected for the first time and astronomy changed for ever. Until then, investigation of the universe had depended on electromagnetic radiation: visible light, radio, X-rays and the rest. But gravitational waves – ripples in the fabric of space and time – are unrelenting, passing through barriers that stop light dead. At the two 4-kilometre long LIGO observatories in the US, scientists developed incredibly sensitive detectors, capable of spotting a movement 100 times smaller than the nucleus of an atom. In 2015 they spotted the ripples produced by two black holes spiralling into each other, setting spacetime quivering. This was the first time black holes had ever been directly detected – and it promises far more for the future of astronomy. Brian Clegg presents a compelling story of human technical endeavour and a new, powerful path to understand the workings of the universe.




Ripples in Spacetime


Book Description

A spacetime appetizer -- Relatively speaking -- Einstein on trial -- Wave talk and bar fights -- The lives of stars -- Clockwork precision -- Laser quest -- The path to perfection -- Creation stories -- Cold case -- Gotcha -- Black magic -- Nanoscience -- Follow-up questions -- Space invaders -- Surf's up for Einstein wave astronomy




Neutron Stars, Black Holes and Gravitational Waves


Book Description

Albert Einstein's General Theory of Relativity, published in 1915, made a remarkable prediction: gravitational radiation. Just like light (electromagnetic radiation), gravity could travel through space as a wave and affect any objects it encounters by alternately compressing and expanding them. However, there was a problem. The force of gravity is around a trillion, trillion, trillion times weaker than electromagnetism so the calculated compressions and expansions were incredibly small, even for gravity waves resulting from a catastrophic astrophysical event such as a supernova explosion in our own galaxy. Discouraged by this result, physicists and astronomers didn't even try to detect these tiny, tiny effects for over 50 years. Then, in the late 1960's and early 1970's, two events occurred which started the hunt for gravity waves in earnest. The first was a report of direct detection of gravity waves thousands of times stronger than even the most optimistic calculation. Though ultimately proved wrong, this result started scientists thinking about what instrumentation might be necessary to detect these waves. The second was an actual, though indirect, detection of gravitational radiation due to the effects it had on the period of rotation of two "neutron stars" orbiting each other. In this case, the observations were in exact accord with predictions from Einstein's theory, which confirmed that a direct search might ultimately be successful. Nevertheless, it took another 40 years of development of successively more sensitive detectors before the first real direct effects were observed in 2015, 100 years after gravitational waves were first predicted. This is the story of that hunt, and the insight it is producing into an array of topics in modern science, from the creation of the chemical elements to insights into the properties of gravity itself.




Modern General Relativity


Book Description

Einstein's general theory of relativity is widely considered to be one of the most elegant and successful scientific theories ever developed, and it is increasingly being taught in a simplified form at advanced undergraduate level within both physics and mathematics departments. Due to the increasing interest in gravitational physics, in both the academic and the public sphere, driven largely by widely-publicised developments such as the recent observations of gravitational waves, general relativity is also one of the most popular scientific topics pursued through self-study. Modern General Relativity introduces the reader to the general theory of relativity using an example-based approach, before describing some of its most important applications in cosmology and astrophysics, such as gamma-ray bursts, neutron stars, black holes, and gravitational waves. With hundreds of worked examples, explanatory boxes, and end-of-chapter problems, this textbook provides a solid foundation for understanding one of the towering achievements of twentieth-century physics.




Superradiance


Book Description

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.




The Joy of X


Book Description

A delightful tour of the greatest ideas of math, showing how math intersects with philosophy, science, art, business, current events, and everyday life, by an acclaimed science communicator and regular contributor to the "New York Times."