An award-winning science journalist details the quest to isolate and understand dark matter-and shows how that search has helped us to understand the universe we inhabit. When you train a telescope on outer space, you can see luminous galaxies, nebulae, stars, and planets. But if you add all that together, it constitutes only 15 percent of the matter in the universe. Despite decades of research, the nature of the remaining 85 percent is unknown. We call it dark matter. In The Elephant in the Universe, Govert Schilling explores the fascinating history of the search for dark matter. Evidence for its existence comes from a wealth of astronomical observations. Theories and computer simulations of the evolution of the universe are also suggestive: they can be reconciled with astronomical measurements only if dark matter is a dominant component of nature. Physicists have devised huge, sensitive instruments to search for dark matter, which may be unlike anything else in the cosmos-some unknown elementary particle. Yet so far dark matter has escaped every experiment. Indeed, dark matter is so elusive that some scientists are beginning to suspect there might be something wrong with our theories about gravity or with the current paradigms of cosmology. Schilling interviews both believers and heretics and paints a colorful picture of the history and current status of dark matter research, with astronomers and physicists alike trying to make sense of theory and observation. Taking a holistic view of dark matter as a problem, an opportunity, and an example of science in action, The Elephant in the Universe is a vivid tale of scientists puzzling their way toward the true nature of the universe.

This book is written from the viewpoint that a deep connection exists between cosmology and particle physics. It presents the results and ideas on both the homogeneous and isotropic Universe at the hot stage of its evolution and in later stages. The main chapters describe in a systematic and pedagogical way established facts and concepts on the early and the present Universe. The comprehensive treatment, hence, serves as a modern introduction to this rapidly developing field of science. To help in reading the chapters without having to constantly consult other texts, essential materials from General Relativity and the theory of elementary particles are collected in the appendices. Various hypotheses dealing with unsolved problems of cosmology, and often alternative to each other, are discussed at a more advanced level. These concern dark matter, dark energy, matter-antimatter asymmetry, etc.Particle physics and cosmology underwent rapid development between the first and the second editions of this book. In the second edition, many chapters and sections have been revised, and numerical values of particle physics and cosmological parameters have been updated.

This book is written from the viewpoint that a deep connection exists between cosmology and particle physics. It presents the results and ideas on both the homogeneous and isotropic Universe at the hot stage of its evolution and in later stages. The main chapters describe in a systematic and pedagogical way established facts and concepts on the early and the present Universe. The comprehensive treatment, hence, serves as a modern introduction to this rapidly developing field of science. To help in reading the chapters without having to constantly consult other texts, essential materials from General Relativity and the theory of elementary particles are collected in the appendices. Various hypotheses dealing with unsolved problems of cosmology, and often alternative to each other, are discussed at a more advanced level. These concern dark matter, dark energy, matter-antimatter asymmetry, etc.Particle physics and cosmology underwent rapid development between the first and the second editions of this book. In the second edition, many chapters and sections have been revised, and numerical values of particle physics and cosmological parameters have been updated.

Modified gravity models play an important role in contemporary theoretical cosmology. The present book proposes a novel approach to the topic based on techniques from noncommutative geometry, especially the spectral action functional as a gravity model. The book discusses applications to early universe models and slow-roll inflation models, to the problem of cosmic topology, to non-isotropic cosmologies like mixmaster universes and Bianchi IX gravitational instantons, and to multifractal structures in cosmology.Relations between noncommutative and algebro-geometric methods in cosmology is also discussed, including the occurrence of motives, periods, and modular forms in spectral models of gravity.

Early Universe cosmology is an active area of research and cosmic inflation is a pillar of modern cosmology. Among predictions of inflation, observationally the most important one is the generation of cosmological perturbations from quantum vacuum fluctuations that source all inhomogeneous structures in the Universe, not to mention the large-scale structures such as clusters of galaxies.Cosmological perturbation theory is the basic tool to study the perturbations generated from inflation. There are a few different approaches to primordial cosmological perturbations. In the conventional approach one perturbs the field equations and after quantizing the perturbations by the use of the corresponding action, one calculates the power spectrum of cosmological observables. This approach extends to higher order perturbations such as bispectrum etc., but the analysis becomes increasingly difficult.The delta N formalism, the topic of this book, is an alternative approach. The novelty of this approach is that, under the condition that the scale of interest is very large so that the spatial derivatives may be ignored in the dynamics, it can be applied to all orders in perturbation theory and has a rigorous foundation in general relativity. Thanks to the fact that one can evaluate perturbations with only the knowledge of background solutions, it is proved to be much easier than the conventional approach in evaluating higher order effects in many cases.

Modified gravity models play an important role in contemporary theoretical cosmology. The present book proposes a novel approach to the topic based on techniques from noncommutative geometry, especially the spectral action functional as a gravity model. The book discusses applications to early universe models and slow-roll inflation models, to the problem of cosmic topology, to non-isotropic cosmologies like mixmaster universes and Bianchi IX gravitational instantons, and to multifractal structures in cosmology.Relations between noncommutative and algebro-geometric methods in cosmology is also discussed, including the occurrence of motives, periods, and modular forms in spectral models of gravity.

Preface.

Notation.

Copyright Acknowledgements.

Part One Preliminaries.

Part Two the General Theory of Relativity.

Part Three Applications of Feneral Relativity.

Part Four Formal Developments.

Part Five Cosmology.

Appendix.

Some Useful Numbers.

Index.

Nanohertz Gravitational Wave Astronomy explores the exciting hunt for low frequency gravitational waves by using the extraordinary timing precision of pulsars. The book takes the reader on a tour across the expansive gravitational-wave landscape, from LIGO detections to the search for polarization patterns in the Cosmic Microwave Background, then hones in on the band of nanohertz frequencies that Pulsar Timing Arrays (PTAs) are sensitive to. Within this band may lie many pairs of the most massive black holes in the entire Universe, all radiating in chorus to produce a background of gravitational waves. The book shows how such extra-Galactic gravitational waves can alter the arrival times of radio pulses emanating from monitored Galactic pulsars, and how we can use the pattern of correlated timing deviations from many pulsars to tease out the elusive signal. The book takes a pragmatic approach to data analysis, explaining how it is performed in practice within classical and Bayesian statistics, as well as the numerous strategies one can use to optimize numerical Bayesian searches in PTA analyses. It closes with a complete discussion of the data model for nanohertz gravitational wave searches, and an overview of the past achievements, present efforts, and future prospects for PTAs. The book is accessible to upper division undergraduate students and graduate students of astronomy, and also serves as a useful desk reference for experts in the field. Key features: Contains a complete derivation of the pulsar timing response to gravitational waves, and the overlap reduction function for PTAs. Presents a comprehensive overview of source astrophysics, and the dynamical influences that shape the gravitational wave signals that PTAs are sensitive to. Serves as a detailed primer on gravitational-wave data analysis and numerical Bayesian techniques for PTAs.

Nanohertz Gravitational Wave Astronomy explores the exciting hunt for low frequency gravitational waves by using the extraordinary timing precision of pulsars. The book takes the reader on a tour across the expansive gravitational-wave landscape, from LIGO detections to the search for polarization patterns in the Cosmic Microwave Background, then hones in on the band of nanohertz frequencies that Pulsar Timing Arrays (PTAs) are sensitive to. Within this band may lie many pairs of the most massive black holes in the entire Universe, all radiating in chorus to produce a background of gravitational waves. The book shows how such extra-Galactic gravitational waves can alter the arrival times of radio pulses emanating from monitored Galactic pulsars, and how we can use the pattern of correlated timing deviations from many pulsars to tease out the elusive signal. The book takes a pragmatic approach to data analysis, explaining how it is performed in practice within classical and Bayesian statistics, as well as the numerous strategies one can use to optimize numerical Bayesian searches in PTA analyses. It closes with a complete discussion of the data model for nanohertz gravitational wave searches, and an overview of the past achievements, present efforts, and future prospects for PTAs. The book is accessible to upper division undergraduate students and graduate students of astronomy, and also serves as a useful desk reference for experts in the field. Key features: Contains a complete derivation of the pulsar timing response to gravitational waves, and the overlap reduction function for PTAs. Presents a comprehensive overview of source astrophysics, and the dynamical influences that shape the gravitational wave signals that PTAs are sensitive to. Serves as a detailed primer on gravitational-wave data analysis and numerical Bayesian techniques for PTAs.

Contains the latest developments and technologies from astronomical observatories and telescope facilities on the ground and in space Accompanied by a companion website with examples, tutorials, Python scripts and resources Authored by an observational astronomer with over thirty years of observing and teaching experience

Time is considered as an independent entity which cannot be reduced to the concept of matter, space or field. The point of discussion is the "time flow" conception of N A Kozyrev (1908-1983), an outstanding Russian astronomer and natural scientist. In addition to a review of the experimental studies of "the active properties of time", by both Kozyrev and modern scientists, the reader will find different interpretations of Kozyrev's views and some developments of his ideas in the fields of geophysics, astrophysics, general relativity and theoretical mechanics.

This book contains a systematic and pedagogical exposition of recent developments in particle physics and cosmology. It starts with two introductory chapters on group theory and the Dirac theory. Then it proceeds with the formulation of the Standard Model (SM) of Particle Physics, particle content and symmetries, fully exploiting the material of the first two chapters. It discusses the concept of gauge symmetries and emphasizes their role in particle physics. It then analyses the Higgs mechanism and the spontaneous symmetry breaking (SSB). It explains how the particles (gauge bosons and fermions) after the SSB acquire a mass and get admixed. The various forms of the charged currents are discussed in detail as well as how the parameters of the SM, which cannot be determined by the theory, are fixed by experiment, including the recent LHC data and the Higgs discovery. Quantum chromodynamics is discussed and various low energy approximations to it are presented. The Feynman diagrams are introduced and applied, at the level of first year graduate students.Examples are the evaluation of the decay widths of the gauge bosons and some cross sections for interesting processes such as Rutherford scattering, electron-proton scattering (elementary proton or described by a form factor, and inelastic scattering) and Compton scattering.After that the classic topics like the role of C, P, CP symmetries and the experimental methods needed to verify their conservation or violation are discussed in some detail. Topics beyond the standard model, like supersymmetry for pedestrians and grand unification, are discussed.To this end neutrino oscillations, dark matter and baryon asymmetry are also briefly discussed at the first year graduate level. Finally, the book contains an exhibition of recent developments in cosmology, especially from the elementary particle point of view.

This book takes a reader on a tour of astronomical phenomena: from the vastness of the interstellar medium, to the formation and evolution of stars and planetary systems, through to white dwarfs, neutron stars, and black holes, the final objects of the stellar graveyard. At its heart, this book is a journey through the evolutionary history of the birth, life, and death of stars, but detours are also made to other related interesting topics. This highly accessible story of the observed contents of our Galaxy includes intuitive explanations, informative diagrams, and basic equations, as needed. It is an ideal guide for undergraduates with some physics and mathematics background who are studying astronomy and astrophysics. It is also accessible to interested laypeople, thanks to its limited equations. Key features: Includes coverage of some of the latest exciting research from the field, including star formation, exoplanets, and black holes Can be utilised as a stand-alone textbook for a one-term course or as a supplementary textbook for a more comprehensive course on astronomy and astrophysics Authored by a team respected for research, education, and outreach Shantanu Basu is an astrophysicist and a professor at The University of Western Ontario, Canada. He is known for research contributions on the formation of gravitationally-collapsed objects in the universe: stars, planets, brown dwarfs, and supermassive black holes. He is one of the originators of the migrating embryo scenario of episodic accretion onto young stars. He has been recognized for his teaching excellence and his contributions to the astronomical community include organizing many conferences and training schools. Pranav Sharma is an astronomer and science historian known for his work on the history of the Indian Space Program. He has curated the Space Museum at the B. M. Birla Science Centre (Hyderabad, India). He is in-charge of the history of Indo-French scientific partnership project supported by the Embassy of France in India. He is a national-award-winning science communicator and has extensively worked on the popularization of astronomy education in India.

This book takes a reader on a tour of astronomical phenomena: from the vastness of the interstellar medium, to the formation and evolution of stars and planetary systems, through to white dwarfs, neutron stars, and black holes, the final objects of the stellar graveyard. At its heart, this book is a journey through the evolutionary history of the birth, life, and death of stars, but detours are also made to other related interesting topics. This highly accessible story of the observed contents of our Galaxy includes intuitive explanations, informative diagrams, and basic equations, as needed. It is an ideal guide for undergraduates with some physics and mathematics background who are studying astronomy and astrophysics. It is also accessible to interested laypeople, thanks to its limited equations. Key features: Includes coverage of some of the latest exciting research from the field, including star formation, exoplanets, and black holes Can be utilised as a stand-alone textbook for a one-term course or as a supplementary textbook for a more comprehensive course on astronomy and astrophysics Authored by a team respected for research, education, and outreach Shantanu Basu is an astrophysicist and a professor at The University of Western Ontario, Canada. He is known for research contributions on the formation of gravitationally-collapsed objects in the universe: stars, planets, brown dwarfs, and supermassive black holes. He is one of the originators of the migrating embryo scenario of episodic accretion onto young stars. He has been recognized for his teaching excellence and his contributions to the astronomical community include organizing many conferences and training schools. Pranav Sharma is an astronomer and science historian known for his work on the history of the Indian Space Program. He has curated the Space Museum at the B. M. Birla Science Centre (Hyderabad, India). He is in-charge of the history of Indo-French scientific partnership project supported by the Embassy of France in India. He is a national-award-winning science communicator and has extensively worked on the popularization of astronomy education in India.

Translations of the Yi jing into western languages have been biased towards the yili ('meaning and pattern') tradition, whereas studies of the xiangshu ('image and number') tradition - which takes as its point of departure the imagery and numerology associated with divination and its hexagrams, trigrams, lines, and related charts and diagrams - has remained relatively unexplored. This major new reference work is organised as a Chinese-English encyclopedia, arranged alphabetically according to the pinyin romanisation, with Chinese characters appended. A character index as well as an English index is included. The entries are of two kinds: technical terms and various other concepts related to the 'image and number' tradition, and bio-bibliographical information on Chinese Yi jing scholars. Each entry in the former category has a brief explanation that includes references to the origins of the term, cross-references, and a reference to an entry giving a more comprehensive treatment of the subject.

* Most up-to-date overview of planetary science, generously illustrated * Accessible prose with a unique perspective by professional astronomers active in planetary science research with extensive teaching experience and expertise in history of astronomy and classical astronomy * Detailed appendices that supplement the text including past, current, and future space missions

* Most up-to-date overview of planetary science, generously illustrated * Accessible prose with a unique perspective by professional astronomers active in planetary science research with extensive teaching experience and expertise in history of astronomy and classical astronomy * Detailed appendices that supplement the text including past, current, and future space missions

Ever since 1911, the Solvay Conferences have shaped modern physics. The format is quite different from other conferences as the emphasis is placed on discussion. The 26th edition held in October 2014 in Brussels and chaired by Roger Blandford continued this tradition and addressed some of the most pressing open questions in the fields of astrophysics and cosmology, gathering many of the leading figures working on a wide variety of profound problems.The proceedings contain the 'rapporteur talks' giving a broad overview with unique insights by distinguished renowned scientists. These lectures cover the five sessions: 'Neutron Stars', 'Black Holes', 'Cosmic Dawn', 'Dark Matter' and 'Cosmic Microwave Background'.In the Solvay tradition, the proceedings also include the prepared comments to the rapporteur talks. The discussions among the participants - expert, yet lively and sometimes contentious - have been edited to retain to retain their flavor and are reproduced in full. The reader is taken on a breathtaking ride through 42 years of extraordinary discovery since astrophysics was last on the Solvay program and 57 years since cosmology was last discussed.

The previous Saas-Fee Advanced Course dedicated to the interstellar medium took place in 1972. The tremendous scientific advances that have occurred in this field since then, in particular owing to the availabihty of receivers working at completely unexplored wavelength bands, fuUy justified a new set of lectures. As a consequence, the members of the Swiss Society for Astrophysics and As tronomy voted that "The Galactic Interstellar Medium" should be the subject of the 1991 course. The 21st Saas Fee Advanced Course took place in Les Diablerets from 18 to 23 March 1991, gathering together about 80 participants from all over the world, but mostly from Europe. According to a rule that has proved to lead to success, but also to chal lenge the lecturers' energy, the format of a Saas-Fee Advanced Course consists traditionally of 28 lectures of 45 minutes which take place in the morning and late afternoon, leaving ample time for discussions, self-study, hiking or skiing. Despite the inordinate work load imposed, this year's lecturers felt that the subject was sufficiently dense to increase the lecture time by 1/3! This proved judicious and left more time for questions and discussions during the lectures.

The cutting-edge science that is taking the measure of the universe The Little Book of Cosmology provides a breathtaking look at our universe on the grandest scales imaginable. Written by one of the world's leading experimental cosmologists, this short but deeply insightful book describes what scientists are revealing through precise measurements of the faint thermal afterglow of the Big Bang-known as the cosmic microwave background, or CMB-and how their findings are transforming our view of the cosmos. Blending the latest findings in cosmology with essential concepts from physics, Lyman Page first helps readers to grasp the sheer enormity of the universe, explaining how to understand the history of its formation and evolution in space and time. Then he sheds light on how spatial variations in the CMB formed, how they reveal the age, size, and geometry of the universe, and how they offer a blueprint for the formation of cosmic structure. Not only does Page explain current observations and measurements, he describes how they can be woven together into a unified picture to form the Standard Model of Cosmology. Yet much remains unknown, and this incisive book also describes the search for ever deeper knowledge at the field's frontiers-from quests to understand the nature of neutrinos and dark energy to investigations into the physics of the very early universe.

A concise introduction to the greatest questions of modern cosmology. What came before the big bang? How will the universe evolve into the future? Will there be a big crunch? Questions like these have no definitive answers, but there are many contending theories. In A Little Book about the Big Bang, physicist and writer Tony Rothman guides expert and uninitiated readers alike through the most compelling mysteries surrounding the nature and origin of the universe. Cosmologists are busy these days, actively researching dark energy, dark matter, and quantum gravity, all at the foundation of our understanding of space, time, and the laws governing the universe. Enlisting thoughtful analogies and a step-by-step approach, Rothman breaks down what is known and what isn't and details the pioneering experimental techniques scientists are bringing to bear on riddles of nature at once utterly basic and stunningly complex. In Rothman's telling, modern cosmology proves to be an intricate web of theoretical predictions confirmed by exquisitely precise observations, all of which make the theory of the big bang one of the most solid edifices ever constructed in the history of science. At the same time, Rothman is careful to distinguish established physics from speculation, and in doing so highlights current controversies and avenues of future exploration. The idea of the big bang is now almost a century old, yet with each new year comes a fresh enigma. That is scientific progress in a nutshell: every groundbreaking discovery, every creative explanation, provokes new and more fundamental questions. Rothman takes stock of what we have learned and encourages readers to ponder the mysteries to come.

'Everything you wanted to know about physics but were afraid to ask' Priyamvada Natarajan, author of Mapping the Heavens __________________________ When leading theoretical physicist Professor Michael Dine was asked where you could find an accessible book that would teach you about the Big Bang, Dark Matter, the Higgs boson and the cutting edge of physics now, he had nothing he could recommend. So he wrote it himself. In This Way to the Universe, Dine takes us on a fascinating tour through the history of modern physics - from Newtonian mechanics to quantum, from particle to nuclear physics - delving into the wonders of our universe at its largest, smallest, and within our daily lives. If you are looking for the one book to help you understand physics, written in language anyone can follow, this is it. __________________________ 'An extraordinary journey into what we know, what we hope to know, and what we don't know, about the universe and the laws that govern it' Leonard Susskind, author of The Theoretical Minimum series 'This book is a rare event . . . presented by someone who is a true master' Sean Carroll, author of From Eternity to Here 'Dine's enthusiastic storytelling makes the read worth it for those who want to finally wrap their mind around string theory or the Higgs boson' Tess Joosse, Scientific American

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.