This is the first complete translation into a modern language of the first part of the pagan Neoplatonist Simplicius of Cilicia's commentary on Aristotle's argument that the world neither came to be nor will perish. It is notable and unusual among the commentaries because Simplicius includes in his discussion lengthy representations of the Christian John Philoponus' criticisms of Aristotle along with his own, frequently heavily sarcastic, responses.

Over the last forty years, scientists have uncovered evidence that if the Universe had been forged with even slightly different properties, life as we know it - and life as we can imagine it - would be impossible. Join us on a journey through how we understand the Universe, from its most basic particles and forces, to planets, stars and galaxies, and back through cosmic history to the birth of the cosmos. Conflicting notions about our place in the Universe are defined, defended and critiqued from scientific, philosophical and religious viewpoints. The authors' engaging and witty style addresses what fine-tuning might mean for the future of physics and the search for the ultimate laws of nature. Tackling difficult questions and providing thought-provoking answers, this volumes challenges us to consider our place in the cosmos, regardless of our initial convictions.

With exoplanets being discovered daily, Earth is still the only planet we know of that is home to creatures who seek a coherent explanation for the structure, origins, and fate of the universe, and of humanity s place within it. Today, science and religion are the two major cultural entities on our planet that share this goal of coherent understanding, though their interpretation of evidence differs dramatically. Many scientists look at the known universe and conclude we are here by chance. The renowned astronomer and historian of science Owen Gingerich looks at the same evidence along with the fact that the universe is comprehensible to our minds and sees it as proof for the planning and intentions of a Creator-God. He believes that the idea of a universe without God is an oxymoron, a self-contradiction. God s Planet" exposes the fallacy in thinking that science and religion can be kept apart.

Gingerich frames his argument around three questions: Was Copernicus right, in dethroning Earth from its place at the center of the universe? Was Darwin right, in placing humans securely in an evolving animal kingdom? And was Hoyle right, in identifying physical constants in nature that seem singularly tuned to allow the existence of intelligent life on planet Earth? Using these episodes from the history of science, Gingerich demonstrates that cultural attitudes, including religious or antireligious beliefs, play a significant role in what passes as scientific understanding. The more rigorous science becomes over time, the more clearly God s handiwork can be comprehended."

High Resolution K-Band Images of the Galactic Centre.- Circumnuclear Populations in Nearby AGN.- The Ionizing Radiation Field in the Galactic Centre and the Nature of Liners.- The Photoionization Mechanism of LINERs: Stellar and Nonstellar.- The Starburst in the Wolf-Rayet Nucleus of the LINER NGC 6764.- Activity in LINER and Starburst Galaxies.- X-Ray Luminous IRAS Galaxies.- Parametric Relations of H II Galaxies.- Spectroscopic Evolutionary Synthesis Models of Wolf-Rayet Galaxies.- UIT Observations of NGC 1275.- The Starburst Model for the Optical Variability of the Seyfert 1 Galaxies NGC 4151 and NGC 5548.- Testing the Consistency of the Starburst Scenario for Active Galactic Nuclei.- The Ca II Triplet Lines in Starbust and Active Galactic Nuclei.- Where Are the Broad Lines in Seyfert 2S?.- Radio Emission in Active Galaxies: The Starburst Scenario.- The Host Galaxies of Nearby Seyfert 1 Nuclei.- X-Ray, UV and FIR Emission of Seyfert Galaxies.- Nitrogen and Helium Pollution in H II Galaxies and AGNs.- Star Formation and AGN.- The Nucleus of the Cygnus A Galaxy at High Resolution.- A Thick Reflection Nebula Illuminated by a Power Law.- Shock and Photoionization Models for Infrared Lines from Active Galactic Nuclei.- Radiation from Arbitrarily Shaped Objects in the Vicinity of Kerr Black Holes.- The Vertical Structure and Radiation Fields of Accretion Discs in the Centres of AGNs.- Is There a Precession-Type Movement in the Nucleus of NGC 4151?.- Emission Line Variability in NGC 4593 and NGC 5548.- Evidence for Anisotropie Radiation in 3C 227.- The ENLR of NGC 4151: Spatial Variations of the Line Ratios.- Testing the Anisotropy of the Central Engine from Extended Emission Line Regions.- The Polarization-Redshift Relation in Radio Galaxies.- Structure of Interacting Elliptical Radio Galaxies.- Activity in Colliding Galaxies.- List of Forthcoming Papers.- The 'KLUWER' LaTeX Style File: Instructions for Authors.

From one of our foremost thinkers and public intellectuals, a radical new view of the nature of time and the cosmos What is time?This deceptively simple question is the single most important problem facing science as we probe more deeply into the fundamentals of the universe. All of the mysteries physicists and cosmologists face--from the Big Bang to the future of the universe, from the puzzles of quantum physics to the unification of forces and particles--come down to the nature of time.The fact that time is real may seem obvious. You experience it passing every day when you watch clocks tick, bread toast, and children grow. But most physicists, from Newton to Einstein to today's quantum theorists, have seen things differently. The scientific case for time being an illusion is formidable. That is why the consequences of adopting the view that time is real are revolutionary.Lee Smolin, author of the controversial bestseller The Trouble with Physics, argues that a limited notion of time is holding physics back. It's time for a major revolution in scientific thought. The reality of time could be the key to the next big breakthrough in theoretical physics.What if the laws of physics themselves were not timeless? What if they could evolve? Time Reborn offers a radical new approach to cosmology that embraces the reality of time and opens up a whole new universe of possibilities. There are few ideas that, like our notion of time, shape our thinking about literally everything, with huge implications for physics and beyond--from climate change to the economic crisis. Smolin explains in lively and lucid prose how the true nature of time impacts our world.

Black holes. What even are they? In brief, a black hole is a region of spacetime so curved by gravity that even light cannot escape it. They're peculiar objects - and notoriously difficult to understand - but are actually a fascinating fusion of the simple and the complex. Although the mathematics describing their behaviour is fiendishly difficult, we can explore the subject by starting with basic principles and straightforward thought experiments. Read on to uncover what's inside a black hole, how scientists discovered this amazing phenomena, even what to do if you find yourself falling into one... and since no one is likely to turn up and help (you'll find out why), what you need to do to escape! Common myths about black holes are dispelled, there is guidance on how to win several Nobel prizes, and the eventual fate of the entire Universe is revealed (maybe)... A little bit of time travel might also be involved!

From the New York Times bestselling creator of Lost in Translation, A Small Illustrated Guide to the Universe is a delicately existential and welcoming exploration of the cosmos - one that examines and marvels at the astonishing principles, laws, and phenomena that we exist alongside, that surround us. Have you ever found yourself wondering what we might have in common with stars or why the Moon never leaves us? Thinking about the precise dancing of planets, the passing of time or the nature of natural things? Our world is full of unshakeable mystery, and although we live in a civilisation more complicated than ever, there is beauty and reassurance to be found in knowing how and why.

Einstein's general theory of relativity can be a notoriously difficult subject for students approaching it for the first time, with arcane mathematical concepts such as connection coefficients and tensors adorned with a forest of indices. This book is an elementary introduction to Einstein's theory and the physics of curved space-times that avoids these complications as much as possible. Its first half describes the physics of black holes, gravitational waves and the expanding Universe, without using tensors. Only in the second half are Einstein's field equations derived and used to explain the dynamical evolution of the early Universe and the creation of the first elements. Each chapter concludes with problem sets and technical mathematical details are given in the appendices. This short text is intended for undergraduate physics students who have taken courses in special relativity and advanced mechanics.

Einstein's general theory of relativity can be a notoriously difficult subject for students approaching it for the first time, with arcane mathematical concepts such as connection coefficients and tensors adorned with a forest of indices. This book is an elementary introduction to Einstein's theory and the physics of curved space-times that avoids these complications as much as possible. Its first half describes the physics of black holes, gravitational waves and the expanding Universe, without using tensors. Only in the second half are Einstein's field equations derived and used to explain the dynamical evolution of the early Universe and the creation of the first elements. Each chapter concludes with problem sets and technical mathematical details are given in the appendices. This short text is intended for undergraduate physics students who have taken courses in special relativity and advanced mechanics.

In Our Mathematical Universe, Max Tegmark, one of the most original physicists at work today, leads us on an astonishing journey to explore the mysteries uncovered by cosmology and to discover the nature of reality Part-history of the cosmos, part-intellectual adventure, Our Mathematical Universe travels from the Big Bang to the distant future via parallel worlds, across every possible scale - from the sub-atomic to the intergalactic - showing how mathematics provides the answers to our questions about the world. Where do we come from? What makes the universe the way it is? In essence, why are we here? With dazzling clarity, Max Tegmark ponders these deep mysteries and allows us to grasp the most cutting-edge and mind-boggling theories of physics. What he proposes is an elegant and fascinating idea: that our physical world not only is described by mathematics, but that it is mathematics. 'Our Mathematical Universe is nothing if not impressive. Brilliantly argued and beautifully written, it is never less than thought-provoking about the greatest mysteries of our existence' - New York Times 'An amazing ride through the rich landscape of contemporary cosmology... Physics could do with more characters like Tegmark... an imaginative intellect and a charismatic presence' - Clive Cookson, Financial Times Max Tegmark is author or co-author of more than 200 technical papers, twelve of which have been cited more than 500 times. He has featured in dozens of science documentaries, and his work with the SDSS collaboration on galaxy clustering shared the first prize in Science magazine's "Breakthrough of the Year: 2003". He holds a Ph.D from the University of California, Berkeley, and is a physics professor at MIT.

Written by an international leader in the field, this is a coherent and accessible account of the concepts that are now vital for understanding cutting-edge work on supermassive black holes. These include accretion disc misalignment, disc breaking and tearing, chaotic accretion, the merging of binary supermassive holes, the demographics of supermassive black holes, and the defining effects of feedback on their host galaxies. The treatment is largely analytic and gives in-depth discussions of the underlying physics, including gas dynamics, ideal and non-ideal magnetohydrodynamics, force-free electrodynamics, accretion disc physics, and the properties of the Kerr metric. It stresses aspects where conventional assumptions may be inappropriate and encourages the reader to think critically about current models. This volume will be useful for graduate or Masters courses in astrophysics, and as a handbook for active researchers in the field. eBook formats include colour figures while print formats are greyscale only.

Astrobiology, the study of life and its existence in the universe, is now one of the hottest areas of both popular science and serious academic research, fusing biology, chemistry, astrophysics, and geology. In this masterful introduction, Lewis Dartnell explores its latest findings, and delves into some of the most fascinating questions in science. What actually is 'life'? Could it exist on other planets? Could alien cells be based on silicon rather than carbon, or need ammonia instead of water? Introducing some of the most extreme lifeforms on Earth - those thriving in boiling acid or huddled around deep-sea volcanoes - Dartnell takes us on a tour of the universe to reveal how deeply linked we are to our cosmic environment, and shows why the Earth is so uniquely suited for the development of life.

This book offers a systematic exposition of conformal methods and how they can be used to study the global properties of solutions to the equations of Einstein's theory of gravity. It shows that combining these ideas with differential geometry can elucidate the existence and stability of the basic solutions of the theory. Introducing the differential geometric, spinorial and PDE background required to gain a deep understanding of conformal methods, this text provides an accessible account of key results in mathematical relativity over the last thirty years, including the stability of de Sitter and Minkowski spacetimes. For graduate students and researchers, this self-contained account includes useful visual models to help the reader grasp abstract concepts and a list of further reading, making this an ideal reference companion on the topic. This title, first published in 2016, has been reissued as an Open Access publication on Cambridge Core.

Modern cosmology tells us that the universe is remarkably 'fine-tuned' for life. If the constants of physics or the initial conditions at the Big Bang were different by the smallest of margins then the universe would have been dull and lifeless. Why should the universe be so accommodating to life? Many cosmologists believe that the existence of many universes can explain why ours is so special. In this book Rodney Holder subjects this 'multiverse' hypothesis to rigorous philosophical critique. A multitude of problems is exposed. Going substantially further than existing treatments, Holder argues that divine design is the best explanation for cosmic fine-tuning, specifically that design by God is a superior explanation in terms of both initial plausibility and explanatory power, and is therefore the most rational position to take on the basis of the cosmological data.

This is a concise introduction to modern astrophysics for physicists, with a focus on galaxy dynamics and the discovery of dark matter halos in galaxies. Part I summarizes important discoveries in observational astronomy and astrophysics, in a manner accessible to those who are new to the topic. Building on this foundation, Part II describes the study of dark matter and provides more detail on galactic dynamics. Important physical concepts that form the basis of key astrophysical phenomena are explained, avoiding unnecessary technicalities and complex derivations. The approach is semi-empirical and emphasizes the importance of key measurements and observations in formulating fundamental theoretical questions and developing their solutions. Students are encouraged to develop a deep understanding of major discoveries and contemporary research topics, beyond the simple application of practical models and formulae, as a bridge to more advanced study in astrophysics.

This book contains the proceedings of the first large IAU Symposium dedicated to the bulges of spiral galaxies. Detailed attention is paid to the bulge of the Milky Way, one of the major building blocks of this system. Topics include the definition of the bulge in our Galaxy and its relation to the so-called spheroid. Discussions are presented regarding the stars contained in this bulge, their astrophysical properties, their motions and the metallicity variations which appear to be present. The possible existence of a bar in the bulge and its origin and future are also examined. The same topics are discussed in less detail for the bulges of other galaxies.

Astrophysics is the physics of the stars, and more widely the physics of the Universe. It enables us to understand the structure and evolution of planetary systems, stars, galaxies, interstellar gas, and the cosmos as a whole. In this Very Short Introduction, the leading astrophysicist James Binney shows how the field of astrophysics has expanded rapidly in the past century, with vast quantities of data gathered by telescopes exploiting all parts of the electromagnetic spectrum, combined with the rapid advance of computing power, which has allowed increasingly effective mathematical modelling. He illustrates how the application of fundamental principles of physics - the consideration of energy and mass, and momentum - and the two pillars of relativity and quantum mechanics, has provided insights into phenomena ranging from rapidly spinning millisecond pulsars to the collision of giant spiral galaxies. This is a clear, rigorous introduction to astrophysics for those keen to cut their teeth on a conceptual treatment involving some mathematics. ABOUT THE SERIES: The Very Short Introductions series from Oxford University Press contains hundreds of titles in almost every subject area. These pocket-sized books are the perfect way to get ahead in a new subject quickly. Our expert authors combine facts, analysis, perspective, new ideas, and enthusiasm to make interesting and challenging topics highly readable

Working physicists, and especially astrophysicists, value a good `back-of-the-envelope' calculation, meaning a short, elegant computation or argument that starts from general principles and leads to an interesting result. This book guides students on how to understand astrophysics using general principles and concise calculations - endeavouring to be elegant where possible and using short computer programs where necessary. The material proceeds in approximate historical order. The book begins with the Enlightenment-era insight that the orbits of the planets is easy, but the orbit of the Moon is a real headache, and continues to deterministic chaos. This is followed by a chapter on spacetime and black holes. Four chapters reveal how microphysics, especially quantum mechanics, allow us to understand how stars work. The last two chapters are about cosmology, bringing us to 21st-century developments on the microwave background and gravitational waves.

Discusses the wide range of chemistry in astronomical environments with an emphasis on the description of molecular processes that critically influence the nature and evolution of astronomical objects and the identification of specific observations that directly address significant astronomical questions. The subject areas of the symposium included atomic and molecular processes at low and high temperatures and photon interactions, the chemical structure of molecular clouds in the Milky Way and in external galaxies, the chemistry of outflows and their interactions with the interstellar medium, the chemical connections between the interstellar medium, and the solar system and pregalactic chemistry.

Aristotle believed that the outermost stars are carried round us on a transparent sphere. There are directions in the universe and a preferred direction of rotation. The sun moon and planets are carried on different revolving spheres. The spheres and celestial bodies are composed of an everlasting fifth element, which has none of the ordinary contrary properties like heat and cold which could destroy it, but only the facility for uniform rotation. But this creates problems as to how the heavenly bodies create light, and, in the case of the sun, heat. The topics covered in this part of Simplicius' commentary are the speeds and distances of the stars; that the stars are spherical; why the sun and moon have fewer motions than the other five planets; why the sphere of the fixed stars contains so many stars whereas the other heavenly spheres contain no more than one (Simplicius has a long excursus on planetary theory in his commentary on this chapter); discussion of people's views on the position, motion or rest, shape, and size of the earth; that the earth is a relatively small sphere at rest in the centre of the cosmos.

With stunning regularity, the search for our cosmic roots has been yielding remarkable new discoveries about the universe and our place in it. In his compelling book, Origins: The Quest for Our Cosmic Roots, veteran science journalist Tom Yulsman chronicles the latest discoveries and describes in clear and engaging terms what they mean. From the interior of protons to the outer reaches of the universe, and from the control room of one of the world's most powerful particle accelerators to an observatory atop the tallest mountain in the Pacific basin, Yulsman takes readers on a fantastic voyage at the cutting edge of science. How could the universe have sprouted from absolute nothingness? What is the origin of galaxies? How do stars and planets form? And despite what now seem to be incredible odds, how did Earth come to be a rich oasis of biodiversity-one that has given rise to a species intelligent enough to ask these questions? In laying out the answers, Origins addresses some of the most profound issues humans have ever confronted.

Applications of quantum field theoretical methods to gravitational physics, both in the semiclassical and the full quantum frameworks, require a careful formulation of the fundamental basis of quantum theory, with special attention to such important issues as renormalization, quantum theory of gauge theories, and especially effective action formalism. The first part of this graduate textbook provides both a conceptual and technical introduction to the theory of quantum fields. The presentation is consistent, starting from elements of group theory, classical fields, and moving on to the effective action formalism in general gauge theories. Compared to other existing books, the general formalism of renormalization in described in more detail, and special attention paid to gauge theories. This part can serve as a textbook for a one-semester introductory course in quantum field theory. In the second part, we discuss basic aspects of quantum field theory in curved space, and perturbative quantum gravity. More than half of Part II is written with a full exposition of details, and includes elaborated examples of simplest calculations. All chapters include exercises ranging from very simple ones to those requiring small original investigations. The selection of material of the second part is done using the "must-know" principle. This means we included detailed expositions of relatively simple techniques and calculations, expecting that the interested reader will be able to learn more advanced issues independently after working through the basic material, and completing the exercises.

After more than half a century since their unexpected discovery and identification as neutron stars, the observation and understanding of pulsars touches upon many areas of astronomy and astrophysics. The literature on pulsars is vast and the observational techniques used now cover the whole of the electromagnetic spectrum from radio to gamma-rays. Now in its fifth edition, this volume has been reorganised and features new material throughout. It provides an introduction in historical and physical terms to the many aspects of neutron stars, including condensed matter, physics of the magnetosphere, supernovae and the development of the pulsar population, propagation in the interstellar medium, binary stars, gravitation and general relativity. The current development of a new generation of powerful radio telescopes, designed with pulsar research in mind, makes this survey and guide essential reading for a growing body of students and astronomers.

Yet over the past few decades, physicists have discovered a phenomenon that operates outside the confines of space and time: nonlocality - the ability of two particles to act in harmony no matter how far apart they may be. If space isn't what we thought it was, then what is it? In Spooky Action at a Distance, the award-winning journalist George Musser sets out to answer that question. He guides us on an epic journey into the lives of experimental physicists observing particles acting in tandem, astronomers finding galaxies that look statistically identical, and cosmologists hoping to unravel the paradoxes surrounding the big bang. He traces the contentious debates over nonlocality through major discoveries and disruptions of the twentieth century and shows how scientists faced with the same undisputed experimental evidence develop wildly different explanations for that evidence. Their conclusions challenge our understanding of the origins of the universe - and they suggest a new grand unified theory of physics.