This book brings together reviews from leading international authorities on the developments in the study of dark matter and dark energy, as seen from both their cosmological and particle physics side. Studying the physical and astrophysical properties of the dark components of our Universe is a crucial step towards the ultimate goal of unveiling their nature. The work developed from a doctoral school sponsored by the Italian Society of General Relativity and Gravitation. The book starts with a concise introduction to the standard cosmological model, as well as with a presentation of the theory of linear perturbations around a homogeneous and isotropic background. It covers the particle physics and cosmological aspects of dark matter and (dynamical) dark energy, including a discussion of how modified theories of gravity could provide a possible candidate for dark energy. A detailed presentation is also given of the possible ways of testing the theory in terms of cosmic microwave background, galaxy redshift surveys and weak gravitational lensing observations. Included is a chapter reviewing extensively the direct and indirect methods of detection of the hypothetical dark matter particles. Also included is a self-contained introduction to the techniques and most important results of numerical (e.g. N-body) simulations in cosmology. " This volume will be useful to researchers, PhD and graduate students in Astrophysics, Cosmology Physics and Mathematics, who are interested in cosmology, dark matter and dark energy.

The NATO Advanced Study Institute on The Nuclear Equatioo of State was held at Peiiiscola Spain from May 22- June 3, 1989. The school was devoted to the advances, theoretical and experimental, made during the past fifteen years in the physics of nuclear matter under extreme conditions, such as high compression and high temperature. Moie than 300 people had applied for participatio- this demonstrates the tremendous interest in the various subjects presented at the school. Indeed, the topic of this school, namely the Nuclear Equatioo of State, * plays the central role in high energy heavy ion collisions; * contains the intriguing possibilities of various phase transitions (gas - vapor, meson condensation, quark - gluon plasma); * plays an important role in the static and dynamical behavior of stars, especially in supernova explosions and in neutron star stability. The investigation on the nuclear equation of state can only be accomplished in the laboratory by compressing and heating up nuclear matter and the only mechanism known to date to achieve this goal is through shock compression and -heating in violent high energy heavy ion collisions. This key mechanism has been proposed and highly disputed in of high energy heavy ion physics, the early 70's. It plays a central role in the whole field and particularly in our discussions during the two weeks at Peiiiscola.

Multiply charged ions have always been in the focus of atomic physics, astrophysics, plasma physics, and theoretical physics. Within the last few years, strong progress has been achieved in the development of ion sources, ion storage rings, ion traps, and methods to cool ions. As a consequence, nowadays, experiments with ensembles of multiply charged ions of brilliant quality are performed in many laboratories. The broad spectrum of the experiments demonstrates that these ions are an extremely versatile tool for investigations in pure and applied physics. It was the aim of this ASI to bring together scientists working in different fields of research with multiply charged ions in order to get an overview of the state of the art, to sound out possibilities for fruitful cooperations, and to discuss perspectives for the future. Accordingly, the programme of the ASI reached from established areas like QED calculations, weak interactions, x-ray astronomy, x-ray lasers, multi photon excitation, heavy-ion induced fusion, and ion-surface interactions up to the very recently opened areas like bound-beta decay, laser and x-ray spectroscopy, and spectrometry of ions in rings and traps, and the interaction of highly charged ions with biological cells. Impressive progress in nearly all of the fields could be reported during the meeting which is documented by the contributions to this volume. The theoretical understand ing of QED and correlation effects in few-electron heavy ions is rapidly developing."

The study of classical electromagnetic fields is an adventure. The theory is complete mathematically and we are able to present it as an example of classical Newtonian experimental and mathematical philosophy. There is a set of foundational experiments, on which most of the theory is constructed. And then there is the bold theoretical proposal of a field-field interaction from James Clerk Maxwell.

This textbook presents the theory of classical fields as a mathematical structure based solidly on laboratory experiments. Here the student is introduced to the beauty of classical field theory as a gem of theoretical physics. To keep the discussion fluid, the history is placed in a beginning chapter and some of the mathematical proofs in the appendices. Chapters on Green's Functions and Laplace's Equation and a discussion of Faraday's Experiment further deepen the understanding. The chapter on Einstein's relativity is an integral necessity to the text. Finally, chapters on particle motion and waves in a dispersive medium complete the picture. High quality diagrams and detailed end-of-chapter questions enhance the learning experience."

The Golden Oldies series of the journal General Relativity and Gravitation reprints important papers in general relativity theory that were published 30 or more years ago and are either hard to get hold of, or were originally printed in a language other than English. They play a key part in making these important papers readily accessible today, in the language that has now become the lingua franca of scientific publication. The value of this reprinting is enhanced by an accompanying editorial note for each paper, which briefly explains the significance of the work and where it has subsequently led to, together with a biographical note about the author or authors. This volume presents a selection of 14 rarities among the Golden Oldies grouped in the three categories "Basic results in differential geometry and general relativity," "Discussion of physical effects" and "Basic exact solutions and their interpretation." Researchers in the field will appreciate having these important papers collected in one book for the first time. Reprinted from the journal General Relativity and Gravitation.

Alfred North Whitehead (1861-1947) was a prominent English mathematician and philosopher who co-authored the highly influential Principia Mathematica with Bertrand Russell. Originally published in 1922, this book forms the follow-up volume to The Principles of Natural Knowledge (1919) and The Concept of Nature (1920). In it, Whitehead puts forward an alternative theory of relativity, one which goes against the heterogeneity of Einstein's later theories in deducing that 'our experience requires and exhibits a basis in uniformity'. The text is divided into three parts - 'General Principles', 'Physical Applications', and 'Elementary Theory of Tensors' - and exhibits a characteristically ambitious approach in mixing various academic disciplines. This is a fascinating book that will be of value to anyone with an interest in natural science, physics, and philosophy, together with the history of science.

This book contains the proceedings of the 1989 Crafoord Symposium organized by the Royal Swedish Academy of Sciences. The scientific field for the Crafoord Prize of 1989 was decided in 1988 by the Academy to be Magnetospheric Physics. On September 27,1989 the Academy awarded the 1989 Crafoord Prize to Professor J. A. Van Allen, Iowa City, USA "for his pioneer work in space research, in particular for the discovery of the high energy charged particles that are trapped in the Earth's magnetic field and form the radiation belts -often called the Van Allen belts - around the Earth". The subject for the Crafoord Symposium, which was held on September 28-29 at the Royal Swedish Academy of Sciences in Stockholm, was Magnetospheric Physics, Achievements and Prospects. Some seventy of the world's leading scientists in magnetospheric physics (see list of participants) were invited to the Symposium. The program contained only invited papers. After the ?resentation of the Crafoord Prize Laureate, Prof. J . A. Van Allen, and his specially invited lecture: "Active Experiments in Magnetospheric Physics" follows in these proceedings two papers on the achievements of magnetospheric research hitherto. The main part of the proceedings (8 papers) deal with the main theme of the Symposium: How we shall carry on magnetospheric research in the future. The Symposium was organized by five members of the Academy representing the field of space physics: Lars Block (Stockholm), Rolf Bostrom (Uppsala), Kerstin Fredga (Stockholm), Carl-Gunne Fiilthammar (Stockholm) and Bengt Hultqvist (Kiruna, Chairman).

What is unorthodox in this book? Much has happened in the last few years, especially in terms of the somewhat surpris ing rate at which the theories presented herein have been gaining increasing acceptance and support even by the most skeptical professionals. Nevertheless, the purpose of this up-dated Preface is not to tell the biographical and acceptance story behind this book, but to bring together some non-physical and non technical conclusions for those readers who find the physico-mathematical sections of this book too difficult to follow. A secondary purpose is to present here some newer conclu sions, especially in general philosophy and in aesthetics. Yet, the main physico philosophical conclusions presented in this book are not to be summarized here. For that purpose one must tum to the text itself. * * * The theories presented here have been developed in total isolation. They were never presented in "professional conferences," as most current writers do. Whether or not that was important remains to be seen. Hence, all I can state to critics and enthusiastic follow ers alike is the fact that I do not belong to any 'formal discipline', 'pressure group', or 'pro fessional organization'."

This 1985 book consists of essays reviewing progress or reporting original results in areas of the applications of gravity theory to which Professor Bonnor had contributed. In particular, the influence of his work in two important fields of interest to astonomers, physicists and mathematicians, galaxy formation and the study of axisymmetric solutions in general relativity, is well recognised. The essays on galaxies and astrophysical cosmology are related to Professor Bonnor's work on the treatment of perturbations of uniform cosmological models, while the essays on axisymmetric solutions reflect the concerns of his long series of papers on the subject, which began with generating techniques and went on to deal with interpretation of the solutions obtained. In addition there is a number of essays on other topics in gravity theory, including numerical work, mathematical cosmology and gravitational waves.

First published in 1989, this book is comprised of invited contributions from speakers at the international workshop, Frontiers in Numerical Relativity, held at the University of Illinois, Urbana-Champaign, in May 1988. Advances in supercomputer technology and computational algorithms have stimulated rapid progress in attempts to understand, through numerical means, such diverse phenomena as gravitational radiation emission from astrophysical sources, the evolution of inhomogenous cosmologies and its effects on nucleosynthesis, cosmic string interactions, the formation of 'naked singularities' and the cosmic censorship conjecture and the dynamics of black holes. The book should be of interest to researchers and graduate students in the field of general relativity, astrophysics and applied numerical analysis who wish to understand developments in computer studies of general relativity at the time of publication.

After pioneering this technology and growing the market, COMSAT fell prey to changes in government policy and to its own lack of entrepreneurial talent. The author explores the factors which contributed to this rise and fall of COMSAT.

Jean-Pierre Vigier continually labeled one of les heretiques de la science, l'eternel resistant et le patriarche is yet a pillar of modern physics and mathematics, with one leg firmly planted in theory and the other in empiricism spanning a career of nearly 60 years with a publication vitae quickly approaching 400! He wrote of his mentor Louis de Broglie "Great physicists fight great battles", which perhaps applies even more so to 1 Jean-Pierre Vigier himself . If fortune allows a visit to Paris, reported to be the city of love, and certainly one of the most beautiful and interesting cities in the world; one has been treated to a visual and cultural feast. For example a leisurely stroll from the Musee du Louvre along the Champs-Elysees to the Arc de Triomphe would instill even the least creative soul with the entelechies of a poets muse. It is perhaps open to theoretical interpretation, but if causal conditions have allowed one to be a physicist, visiting Paris, one may have taken opportunity to visit the portion of the old Latin quarter in place Jussieu where Pierre et Marie Curie Universite, reported to be 'the best university in France', is stationed.

Ebenezer Cunningham was a British mathematician and Cambridge graduate with an intense interest in the theory of special relativity, a subject that was just beginning to be recognised as he wrote. This book, first published by Cambridge University Press in 1914, was one of the first treatises in the English language to focus on special relativity. Its publication firmly established Cunningham as one of the greatest minds in the field. Within this volume, Cunningham firstly offers the reader a preface contextualising the progress of the study of relativity thus far. His chapters then process to relate relativity to existing physical theory, expanding on the relativity of Newtonian dynamics, electron theory and theories of Albert Einstein amongst others. This book is thoroughly and engagingly written, and promises to fascinate all those with an interest in the early study of special relativity.

The Hidden Hypotheses Behind the Big Bang It is quite unavoidable that many philosophical a priori assumptions lurk behind the debate between supporters of the Big Bang and the anti-BB camp. The same battle has been waged in physics between the determinists and the opposing viewpoint. Therefore, by way of introduction to this symposium, I would like to discuss, albeit briefly, the many "hypotheses", essentially of a metaphysical nature, which are often used without being clearly stated. The first hypothesis is the idea that the Universe has some origin, or origins. Opposing this is the idea that the Universe is eternal, essentially without beginning, no matter how it might change-the old Platonic system, opposed by an Aristote lian view! Or Pope Pius XII or Abbe Lemaitre or Friedmann versus Einstein or Hoyle or Segal, etc. The second hypothesis is the need for a "minimum of hypotheses" -the sim plicity argument. One is expected to account for all the observations with a mini mum number of hypotheses or assumptions. In other words, the idea is to "save the phenomena", and this has been an imperative since the time of Plato and Aristotle. But numerous contradictions have arisen between the hypotheses and the facts. This has led some scientists to introduce additional entities, such as the cosmologi cal constant, dark matter, galaxy mergers, complicated geometries, and even a rest mass for the photon. Some of the proponents of the latter idea were Einstein, de Broglie, Findlay-Freundlich, and later Vigier and myself.

This book is an exposition of "semi-Riemannian geometry" (also called "pseudo-Riemannian geometry")--the study of a smooth manifold furnished with a metric tensor of arbitrary signature. The principal special cases are Riemannian geometry, where the metric is positive definite, and Lorentz geometry. For many years these two geometries have developed almost independently: Riemannian geometry reformulated in coordinate-free fashion and directed toward global problems, Lorentz geometry in classical tensor notation devoted to general relativity. More recently, this divergence has been reversed as physicists, turning increasingly toward invariant methods, have produced results of compelling mathematical interest.

This book gives both a comprehensive and detailed account of the current theoretical and observational investigations of the radio galaxy M87 in the Virgo cluster. A number of introductory chapters provide a general overview, which makes the book accessible also to non-specialists in the field.
The remaining chapters are devoted to a detailed treatment of special topics covering all relevant aspects of the galactic structure and jet.

Edgard Gunzig and Pasquale Nardone RGGR Universite Libre de Bruxelles CP231 1050 Bruxelles Belgium The NATO Advanced Research Workshop on "The Origin of Structure in the Universe" was organized to bring together workers in various aspects of relativistic cosmology with the aim of assessing the present status of our knowledge on the formation and evolution of structure. As it happened, the meeting was particularly timely. Only two days before the 30 or so physicists from many countries gathered for a week at the Chateau du Pont d'Oye, in the forests of the southern Belgian province of Luxembourg, newspaper headlines all over the world announced the results of the analysis of the first full year of data from the Cosmic Background Observer Satellite (COBE). This long-awaited confirmation of the theoretically predicted anisotropy in the microwave background radiation opened a new era in observational cos mology. The realization of the new relevance of the subject of the workshop and the questions raised by the observational results, in addition to bring ing TV crews and newspaper journalists, naturally influenced and stimulated many discussions among the participants. The success of the meeting as usual is due to a combination of factors. Besides the high quality of the talks, discussions were encouraged by the warm atmosphere of the Chateau, for which we are grateful to Mme. Camille Orts, and its beautiful surroundings, not to mention the marvelous cuisine.

This book is one result from the 1996 Millimeter-wave Summer School held at the Instituto Nacional de Astrofisica, Optica y Electronica (INAOE), Tonantz- intla, Puebla, Mexico. In collaboration with the University of Massachusetts, INAOE has embarked upon the ambitious project of building the world's largest filled aperture millimeter-wave telescope - the Large Millimeter-wave Tele- scope (LMT), or Gran Telescopio Milimetrico (GTM). The LMT is currently the largest scientific project in Mexico. The summer school had a dual purpose; first, to introduce the Mexican as- tronomical and physics communities to millimeter wavelength astronomy, and second, to provide a forum for a review of several important aspects of the state of the art in observations, theory, interpretation, and technology relevant to this branch of astronomy. The summer school had 18 invited speakers and 44 par- ticipants. The scientific organizing committee (SOC) consisted of Luis Carrasco (UNAM/INAOE, Mexico), Paul Goldsmith (NAIC, Cornell Univ., USA), and Andy Harris (Univ. of Maryland, USA). Members of the local organizing com- mittee (LOC) were Alberto Carramiiiana (INAOE), Emmanuel Mendez Palma (INAOE), Mari Paz Miralles (Harvard-Smithsonian Center for Astrophysics, USA), and William Wall (INAOE).

Radio surveys play an important role in observational cosmology. However, until recently the surveys have been either of wide area but with low sensitivity or of small area with high sensitivity. Both limit the kinds of cosmology that can be carried out with radio surveys. This situation has been revolutionised in the past few years by the availability of new, large-area, high-sensitivity radio surveys at both low and high radio frequencies. These significant improvements allow studies based on both the statistics of the surveys themselves and multiwavelength follow-up of the galaxies and AGN responsible for the radio emission. It is therefore an opportune time to summarise progress in this field with a workshop. This book comprises the proceedings of the `Observational Cosmology with the New Radio Surveys' workshop, held on Tenerife, January 13-15, 1997. Topics covered include: lessons learned and important results from earlier surveys, descriptions of some of the new surveys, clusters of galaxies and large-scale structure, radio source evolution, CMB studies, gravitational lensing and multiwavelength studies of distant radio sources.

This unique volume contains the proceedings of two "Non-Sleeping Universe" conferences: "Stars and the ISM" and "From Galaxies to the Horizon." The book provides an overview of recent developments in a variety of areas, covering a very wide range of spatial and temporal scales.

The nature of time has long puzzled physicists and philosophers. Time potentially has very fundamental yet unknown properties. In 1993 a new model of multi-dimensional time was found to relate closely to properties of the cosmological redshift. An international conference was subsequently convened in April 1996 to examine past, current and new concepts of time as they relate to physics and cosmology. These proceedings incorporate 34 reviews and contributed papers from the conference. The major reviews include observational properties of the redshift, alternative cosmologies, critical problems in cosmology, alternative viewpoints and problems in gravitation theory and particle physics, and new approaches to mathematical models of time. Professionals and students with an interest in cosmology and the structure of the universe will find that this book raises critical problems and explores challenging alternatives to classical viewpoints.

The last decade has been witness to many exciting and rapid developments in the fields of Nuclear Physics and Intermediate Energy Physics, the interface between Nuclear and Elementary Particle Physics. These developments involved to a large extent the sub nucleonic degrees of freedom in nuclei. In deep inelastic lepton scattering from nuclei, for example, it was observed that the quark structure of the nucleon is influenced by the nuclear medium. Also, the spin-dependent structure function of the nucleon was found to differ from sum rules based on SU(3) symmetry, a discrepancy referred to as the "spin crisis". In pion electroproduction at threshold and in the production of pions and other mesons in heavy ion collisions at intermediate energies interesting experimental results have been obtained, which triggered lively theoretical discussions. Furthermore, the search for the quark-gluon plasma phase of hadronic matter, a phase that is supposed to have existed in the first few seconds of the Big Bang, has been intensified. Not only were these developments accompanied by technical developments, such as the building of new experimental facilities, but also extensive theoretical efforts have been directed towards understanding these phenomena. These concerted efforts will hopefully lead to an understanding of the transition from the non-perturbative QCD regime to the perturbative one, in which the quark structure of nucleons is better understood. All of the aforementioned developments occur at a high pace, making it difficult to incorporate them into the courses offered to advanced students.

This volume consists of invited lectures and seminars presented at the NATO Advanced Study Institute "The Infrared and Submillimetre Sky after COBE", which was held at the Centre de Physique Theorique of Les Houches (France) in March 1991. The school has been planned by a Scientific Organizing Committee. It was organized with the aim of providing students and young researchers with an up-to-date account of the Cosmic Microwave Background, the Cosmic Infrared Background (if any), and the infrared emission of the Galaxy, after the early results from COBE (Cosmic Background Explo- rer). It was attended by about sixty researchers from many countries. The lectures and seminars represent a complete coverage of our present knowledge and understanding of: the Early Universe, Large-Scale Structure, Dust in Galaxies, Infrared to Submillimetre Backgrounds, CMB Anisotropies, complementary observations and instrumentation problems, etc. Most of these lectures are reproduced in this volume. Unfortunately, a few lecturers have chosen not to submit their manuscript. I would like to express my gratitude to the Scientific Affairs Division of NATO (North Atlantic Treaty Organization) and to the Theoretical Physics and Astrophysics Sections of the CNRS (Centre National de la Re- cherche Scientifique) for their generous support. Further help was obtain- ed from the DRET (Direction des Recherches, Etudes et Techniques), the CNES (Centre National d'Etudes Spatiales) and the IN2P3 (Institut Natio- nal de Physique Nuc1eaire et de Physique des Particules), which I hereby gratefully acknowledge.

The aim of this book is to present the theory and applications of the relativistic Boltzmann equation in a self-contained manner, even for those readers who have no familiarity with special and general relativity. Though an attempt is made to present the basic concepts in a complete fashion, the style of presentation is chosen to be appealing to readers who want to understand how kinetic theory is used for explicit calculations. The book will be helpful not only as a textbook for an advanced course on relativistic kinetic theory but also as a reference for physicists, astrophysicists and applied mathematicians who are interested in the theory and applications of the relativistic Boltzmann equation.