The mystery of gravity has captivated us for centuries. But what is gravity and how does it work? This engaging book delves into the bizarre and often counter-intuitive world of gravitational physics. Join distinguished astrophysicist Professor Luciano Rezzolla on this virtual journey into Einstein's world of gravity, with each milestone presenting ever more fascinating aspects of gravitation. Through gentle exposure to concepts such as spacetime curvature and general relativity, you will discover some of the most curious consequences of gravitational physics, such as black holes, neutron stars and gravitational waves. The author presents and explains one of the most impressive scientific achievements of recent times: the first image of a supermassive black hole. Written by one of the key scientists involved in producing these results, you'll get a behind-the-scenes view of how the image was captured and discover what happens to matter and light near a black hole.

Stephen Hawking, the Lucasian Professor of Mathematics at Cambridge University, has made important theoretical contributions to gravitational theory and has played a major role in the development of cosmology and black hole physics.

Hawking's early work, partly in collaboration with Roger Penrose, showed the significance of spacetime singularities for the big bang and black holes. His later work has been concerned with a deeper understanding of these two issues. The work required extensive use of the two great intellectual achievements of the first half of the Twentieth Century: general relativity and quantum mechanics; and these are reflected in the reprinted articles. Hawking's key contributions on black hole radiation and the no-boundary condition on the origin of the universe are included.

The present compilation of Stephen Hawking's most important work also includes an introduction by him, which guides the reader though the major highlights of the volume. This volume is thus an essential item in any library and will be an important reference source for those interested in theoretical physics and applied mathematics.

It is an excellent thing to have so many of Professor Hawking's most important contributions to the theory of black holes and space-time singularities all collected together in one handy volume. I am very glad to have them". Roger Penrose (Oxford)

"This was an excellent idea to put the best papers by Stephen Hawking together. Even his papers written many years ago remain extremely useful for those who study classical and quantum gravity. By watching the evolution of his ideas one can get a very clear picture of the development of quantum cosmology during thelast quarter of this century". Andrei Linde (Stanford)

"This review could have been quite short: 'The book contains a selection of 21 of Stephen Hawking's most significant papers with an overview written by the author'. This would be sufficient to convince any researcher, student or librarian to acquire the book, so indisputable is the contribution of this man to the theoretical physics of the last half of our century ... Collected together, these brilliant works constitute a valuable contribution to the literature on modern classical and quantum gravity and cosmology. This book will certainly be a source of inspiration for new generations of physicists entering into this fascinating area of research". D Gal'tsov Classical & Quantum Gravity

The Euclidean approach to Quantum Gravity was initiated almost 15 years ago in an attempt to understand the difficulties raised by the spacetime singularities of classical general relativity which arise in the gravitational collapse of stars to form black holes and the entire universe in the Big Bang. An important motivation was to develop an approach capable of dealing with the nonlinear, non-perturbative aspects of quantum gravity due to topologically non-trivial spacetimes. There are important links with a Riemannian geometry. Since its inception the theory has been applied to a number of important physical problems including the thermodynamic properties of black holes, quantum cosmology and the problem of the cosmological constant. It is currently at the centre of a great deal of interest.This is a collection of survey lectures and reprints of some important lectures on the Euclidean approach to quantum gravity in which one expresses the Feynman path integral as a sum over Riemannian metrics. As well as papers on the basic formalism there are sections on Black Holes, Quantum Cosmology, Wormholes and Gravitational Instantons.

Bringing the material up to date, Black Holes, Wormholes and Time Machines, Second Edition captures the new ideas and discoveries made in physics since the publication of the best-selling first edition. While retaining the popular format and style of its predecessor, this edition explores the latest developments in high-energy astroparticle physics and Big Bang cosmology. The book continues to make the ideas and theories of modern physics easily understood by anyone, from researchers to students to general science enthusiasts. Taking you on a journey through space and time, author Jim Al-Khalili covers some of the most fascinating topics in physics today, including: Black holes Space warps The Big Bang Time travel Wormholes Parallel universes Professor Al-Khalili explains often complex scientific concepts in simple, nontechnical terms and imparts an appreciation of the cosmos, helping you see how time traveling may not be so far-fetched after all.

The Euclidean approach to Quantum Gravity was initiated almost 15 years ago in an attempt to understand the difficulties raised by the spacetime singularities of classical general relativity which arise in the gravitational collapse of stars to form black holes and the entire universe in the Big Bang. An important motivation was to develop an approach capable of dealing with the nonlinear, non-perturbative aspects of quantum gravity due to topologically non-trivial spacetimes. There are important links with a Riemannian geometry. Since its inception the theory has been applied to a number of important physical problems including the thermodynamic properties of black holes, quantum cosmology and the problem of the cosmological constant. It is currently at the centre of a great deal of interest.This is a collection of survey lectures and reprints of some important lectures on the Euclidean approach to quantum gravity in which one expresses the Feynman path integral as a sum over Riemannian metrics. As well as papers on the basic formalism there are sections on Black Holes, Quantum Cosmology, Wormholes and Gravitational Instantons.

This text records the recent events in the development of astrometry. The results of space missions in astrometry, Hipparcos and some results from the Hubble Space telescope are presented. Combined with ground-based results, this provides astrometry results at milliarcsecond resolution. At the same time, the extragalactic reference frame, based on very long baseline interferometry radio positions, is being introduced as the fundamental reference frame. It is now also evident that future optical interferometry space missions can provide an additional improvement in future of orders of magnitude. In addition to presenting the results, the text also discusses different applications based on such accurate astrometric positions.

In part one of Effective Action in Quantum Gravity, the book describes the principles of quantum field theory and the significance of and theory behind effective action. Part two deals with quantum field theory in curved space-time and the effective action. These two parts provide the tools for understanding the rest of the book, which is devoted to selected problems of quantum gravity where the effective action plays a major role. The book assumes only a basic understanding of quantum field theory and general relativity and will be of interest to postgraduate students and researchers in theoretical high-energy physics and gravitational theory.

Essential Relativistic Celestial Mechanics presents a systematic exposition of the essential questions of relativistic celestial mechanics and their relation to relativistic astrometry. The book focuses on the comparison of calculated and measurable quantities that is of paramount importance in using general relativity as a necessary framework in the discussion of high-precision observations and for the construction of accurate dynamical ephemerides. It discusses the results of the general relativistic theory of motion of celestial bodies and describes the relativistic theory of astronomical reference frames, time scales, and the reduction of observations.

This book provides insight into concept of the weak interaction and its integration into the conceptual structure of elementary particle physics. It exhibits the important role of the weak interaction in nuclear, particle and astrophysics together with the close connection between these areas.

The Star and the Whole: Gian-Carlo Rota on Mathematics and Phenomenology, authored by Fabrizio Palombi, is the first book to study Rota's philosophical reflection. Rota (1932 1999) was a leading figure in contemporary mathematics and an outstanding philosopher, inspired by phenomenology, who made fundamental contributions to combinatorial analysis, and trained several generations of mathematicians in his long career at the Massachusetts Institute of Technology (MIT) and the Los Alamos National Laboratory. The first chapter of the book reconstructs Rota's cultural biography and examines his philosophical style, his criticisms of analytical philosophy, and his reflection on Heidegger's thought. The second chapter presents a general picture of Rota's re-elaboration of phenomenology examined in the light of the Husserlian notion of Fundierung. This chapter also illustrates how the star-shape becomes a powerful instrument for understanding the properties of Husserl's mereology and the critique of objectivism. The third chapter is a theoretical reflection on the nature of mathematical entities, and the fourth examines the complex relation of mathematical research with technological applicability and scientific progress. The foreword of the text is written by Robert Sokolowski.

The last decade has witnessed a breathtaking expansion of ideas concerning the origin and evolution of the universe. Researchers in cosmology thus need an unprecedented wide background in diverse areas of physics. Bridging the gap that has developed, Physics of the Early Universe explains the foundations of this subject. This postgraduate-/research-level volume covers cosmology, gauge theories, the standard model, cosmic strings, and supersymmetry.

This book is intended as a supplementary text to the standard course books on theoretical physics and astrophysics, addressing applications and selected problems in theoretical physics and astrophysics, most of which are to a greater or lesser extent associated with electrodynamics.

From a star theoretical physicist, a journey into the world of particle physics and the cosmos -- and a call for a more just practice of science. In The Disordered Cosmos, Dr. Chanda Prescod-Weinstein shares her love for physics, from the Standard Model of Particle Physics and what lies beyond it, to the physics of melanin in skin, to the latest theories of dark matter -- all with a new spin informed by history, politics, and the wisdom of Star Trek. One of the leading physicists of her generation, Dr. Chanda Prescod-Weinstein is also one of fewer than one hundred Black American women to earn a PhD from a department of physics. Her vision of the cosmos is vibrant, buoyantly non-traditional, and grounded in Black feminist traditions. Prescod-Weinstein urges us to recognize how science, like most fields, is rife with racism, sexism, and other dehumanizing systems. She lays out a bold new approach to science and society that begins with the belief that we all have a fundamental right to know and love the night sky. The Disordered Cosmos dreams into existence a world that allows everyone to experience and understand the wonders of the universe.

Astronomical photographs contain an enormous amount of information. This presents extremely interesting problems when one wishes to produce digitized sky atlases, to archive the digitized material, to develop sophisticated devices to do the digitizing, and to create software to process the vast amounts of data. All these activities are necessary to be able to carry out astronomy work. One such activity is the important, large-scale optical identification of objects which also emit radiation at other wavelengths. Other activities of the past decade include a multiplicity of surveys that have been made on galaxies and clusters of galaxies. This book treats, in five sections, the existing and future surveys, their digitization and their impact on astronomy. It is designed to serve as a reference for people in the field and for those who wish to engage in using or producing sky surveys.

.".. is a worthwhile elementary treatment of the cosmology of the early Universe written with a liveliness and simplicity that will surely encourage students to pursue the subject further.''
John D Barrow
Nature, 1989

.".. a superb guide to what is known about cosmology....The authors also leave you with a sense of anticipation and excitement.''
David Hughes
New Scientist, 1989

"The book is well written and interesting, particularly in its use of Chinese stories throughout ... The book contains all the standard material found in such texts. The chapters on the thermodynamics of the Universe are particularly good ... this is a first-rate book of its genre and is heartily recommended."
Kenneth Dunn
Mathematical Reviews, 1993

"The best popular account of the science that explains how the universe can be friendly to life is a book, 'Creation of the Universe', by the Chinese astronomers, Fang Li Zhi and Li Shu Xian. The book was translated into English and published by World Scientific Publishing in 1989. Fang Li Zhi is the famous dissident astronomer now living in exile in the United States. I particularly recommend Chapter 6, with the title 'How Order Was Born of Chaos'. This tells the same story that I am telling you today, but with more detail and more depth."
Freeman J Dyson
Oppenheimer lecture at University of California, Berkeley
Mar 2000

.".. is a worthwhile elementary treatment of the cosmology of the early Universe written with a liveliness and simplicity that will surely encourage students to pursue the subject further.''
John D Barrow
Nature, 1989

.".. a superb guide to what is known about cosmology....The authors also leave you with a sense of anticipation and excitement.''
David Hughes
New Scientist, 1989

"The book is well written and interesting, particularly in its use of Chinese stories throughout ... The book contains all the standard material found in such texts. The chapters on the thermodynamics of the Universe are particularly good ... this is a first-rate book of its genre and is heartily recommended."
Kenneth Dunn
Mathematical Reviews, 1993

"The best popular account of the science that explains how the universe can be friendly to life is a book, 'Creation of the Universe', by the Chinese astronomers, Fang Li Zhi and Li Shu Xian. The book was translated into English and published by World Scientific Publishing in 1989. Fang Li Zhi is the famous dissident astronomer now living in exile in the United States. I particularly recommend Chapter 6, with the title 'How Order Was Born of Chaos'. This tells the same story that I am telling you today, but with more detail and more depth."
Freeman J Dyson
Oppenheimer lecture at University of California, Berkeley
Mar 2000

This book introduces quantum field theory, together with its most important applications to cosmology and astroparticle physics, in a coherent framework. The path integral approach is employed right from the start, and the use of Green functions and generating functionals is illustrated first in quantum mechanics and then in scalar field theory. Massless spin one and two fields are discussed on an equal footing, and gravity is presented as a gauge theory in close analogy with the Yang-Mills case. Concepts relevant to modern research such as helicity methods, effective theories, decoupling, or the stability of the electroweak vacuum are introduced. Various applications such as topological defects, dark matter, baryogenesis, processes in external gravitational fields, inflation and black holes help students to bridge the gap between undergraduate courses and the research literature.

This IAU Symposium brought together researchers who use CCDs and arrays, designers and manufacturers of CCDs and array mosaics, and those who write the software to control these devices and to reduce the large amounts of data contained in each frame. At the meeting such topics as plans for applying the new technology to the new large telescopes that have been built recently and those planned in the near future, new developments in infra-red arrays, advances and concerns with the use of CCDs in photometry and spectroscopy and the creation of large mosaics in photometry and spectroscopy, and the creation of large mosaics of chips which allow larger areas of the sky to be covered in a single frame were discussed. There were sessions devoted to the following topics: new developments in CCD technology; new developments in IR detector arrays; direct imaging with CCDs and other arrays; spectroscopy with CCDs and other arrays; and large field imaging with array mosaics. Scientific results of studies made with this technology were covered in the poster sessions. CCD and array detectors have become the detectors of choice at all the world's optical observatories. Such instruments on small university and college telescopes have turned these telescopes into instruments that can now do observations which in the past were done only on the largest telescopes. CCDs and arrays are known as "the people's detector" because of their ability to turn small telescopes into true research instruments. On large telescopes observations can be made of extremely faint and crowded objects that were impossible to observe before the advent of CCD and Array technology. The proceedings of this meeting should be useful to all those who are interested in the design, manufacture and use of CCDs and arrays for astronomical observations.

The papers in this volume aim to represent the most up-to-date research contributions on the observations, theoretical interpretations, and empirical and physical models of variations observed in solar and stellar irradiances, as well as on Sun-climate connections. Both theoretical studies and irradiance observations show that the energy output of the Sun and solar-type stars varies, changing on time scales related to the short-term surface manifestations of solar/stellar magnetic activity as well as long-term modulations driven by processes in the interiors of the stars. Papers presented in this book point out that at the Earth these variations influence the terrestrial climate, radiative environment and upper atmospheric chemistry.

This book presents experiments which will teach physics relevant to astronomy. The astronomer, as instructor, frequently faces this need when his college or university has no astronomy department and any astronomy course is taught in the physics department. The physicist, as instructor, will find this intellectually appealing when faced with teaching an introductory astronomy course. From these experiments, the student will acquire important analytical tools, learn physics appropriate to astronomy, and experience instrument calibration and the direct gathering and analysis of data. Experiments that can be performed in one laboratory session as well as semester-long observation projects are included.

This book explores the extraordinary difficulties a nation-state's law enforcement and military face in attempting to prevent cyber-attacks. In the wake of recent assaults including the denial of service attack on Estonia in 2007 and the widespread use of the Zeus Trojan Horse software, Susan W. Brenner explores how traditional categories and procedures inherent in law enforcement and military agencies can obstruct efforts to respond to cyberthreats. Brenner argues that the use of a territorially-based system of sovereignty to combat cyberthreats is ineffective, as cyberspace erodes the import of territory. This problem is compounded by the nature of cybercrime as a continually evolving phenomenon driven by rapid and complex technological change. Following an evaluation of the efficacy of the nation-state, the book goes on to explore how individuals and corporations could be integrated into a more decentralized, distributed system of cyberthreat control. Looking at initiatives in Estonia and Sweden which have attempted to incorporate civilians into their cyber-response efforts, Brenner suggests that civilian involvement may mediate the rigid hierarchies that exist among formal agencies and increase the flexibility of any response. This book will be of great interest to students and researchers of information technological law and security studies.

From Nobel Prize-winning physicist P. J. E. Peebles, the story of cosmology from Einstein to today Modern cosmology began a century ago with Albert Einstein's general theory of relativity and his notion of a homogenous, philosophically satisfying cosmos. Cosmology's Century is the story of how generations of scientists built on these thoughts and many new measurements to arrive at a well-tested physical theory of the structure and evolution of our expanding universe. In this landmark book, one of the world's most esteemed theoretical cosmologists offers an unparalleled personal perspective on how the field developed. P. J. E. Peebles was at the forefront of many of the greatest discoveries of the past century, making fundamental contributions to our understanding of the presence of helium and microwave radiation from the hot big bang, the measures of the distribution and motion of ordinary matter, and the new kind of dark matter that allows us to make sense of these results. Taking readers from the field's beginnings, Peebles describes how scientists working in independent directions found themselves converging on a theory of cosmic evolution interesting enough to warrant the rigorous testing it passes so well. He explores the major advances-some inspired by remarkable insights or perhaps just lucky guesses-as well as the wrong turns taken and the roads not explored. He shares recollections from major players in this story and provides a rare, inside look at how science is really done. A monumental work, Cosmology's Century also emphasizes where the present theory is incomplete, suggesting exciting directions for continuing research.

This volume contains the papers presented at the Third Alexander von Humboldt Colloquium on Celestial Mechanics. The papers cover a large range of questions, from the behaviour of dust particles to the stability of the solar system as a whole. The motions of asteroids and their classification into families are also discussed. Specific topics addressed are KAM theory, chaotic motions, resonances, Lyapunov characteristic exponents, perturbation theory and numerical integration.

Foreword; J. Davies, D. Burstein. Introductory Remarks; M. Disney. Interstellar grain evolution and temperatures in spiral galaxies; J. Mayo Greenberg, A. Li. Radiative transfer models; G. Bruzual A. Radiative transfer in dusty galaxies; A.N. Witt. Opacity Diagnostics in spiral galaxies; N.D. Kylafis. Modeling dusty galaxies; G. Magris C., G. Bruzual A. Inclination-dependence of spiral galaxy physical properties: history and tests; D. Burstein, et al. Why a distance selection effect invalidates the Burstein, Haynes and Faber opacity test; J.I. Davies, et al. Statistical tests for opacity; E.A. Valentijn. Statistical measures of internal absorption in spiral galaxies; B. Cunow. The distribution of galactic inclinations; H. Jones, et al. Optical thickness of Sb-Scd galaxies from the Tully--Fisher relation; L. Gouguenhei, et al. Extinction in Sc galaxies at I band and in the 21cm line; R. Giovanelli. Extinction in the galaxy and in galactic discs; G. de Vaucouleurs. Properties of dust in backlit galaxies; W. Keel, R.E. White. The optical depth through NGC 3314A; P. James, P. Puxley. Dust extinction in highly inclined spirals; J. Knapen, et al. An optical search for dusty disks; M. Naslund, S. Joersater. Photometric asymmetry and dust opacity of spiral galaxies; Y.I. Byun. The scale-length test for dust in face-on spirals; J.E. Beckman, et al. Color gradients in spiral galaxies; S. Courteau, J. Holtzman. Constraints on the opacity of spiral disks from near-infrared observations; H.W. Rix. Arcsecond resolution of cold dust in spiral galaxies using optical and NIR imaging -- dust masses increase by nine hundred percent; D.L. Block, et al. Unveiling stars and dust in spiral galaxies;R.F. Pelletier, et al. Azimuthal distribution of dust in NGC 2997; P. Grosbol, et al. Internal extinction in spiral galaxies at optical and near infrared wavelengths; A. Boselli, G. Gavazzi. The opacity of spiral galaxy disks; N. Devereux. The far infrared/stellar energy balance; R. Evans. Opacity from luminosity functions; M. Trewhella, et al. Estimating disk opacities using infrared images; W. van Driel. DIRBE observations of galactic extinction; R.G. Arendt, et al. Kinematics of edge-on galaxies and the opacity of spiral disks; A. Bosma. Spectroscopic studies of the disk and halo of M82; C.D. McKeith, et al. Disk origin and evolution; J. Silk. The luminosity and opacity of galaxies; B. Wang. Dust obscuration in starburst galaxies; D. Calzetti. Polarimetry of dusty edge-on galaxies; R.D. Wolstencroft, S.M. Scarrott. HII regions and extinction in the spiral galaxy M83; S. Ryder, et al. A search for dust in galactic halos; D. Zaritsky. Concluding thoughts and reflections: dust in galaxies; H.A. Thronson Jr.