Based on a Simons Symposium held in 2018, the proceedings in this volume focus on the theoretical, numerical, and observational quest for dark matter in the universe. Present ground-based and satellite searches have so far severely constrained the long-proposed theoretical models for dark matter. Nevertheless, there is continuously growing astrophysical and cosmological evidence for its existence. To address present and future developments in the field, novel ideas, theories, and approaches are called for. The symposium gathered together a new generation of experts pursuing innovative, more complex theories of dark matter than previously considered.This is being done hand in hand with experts in numerical astrophysical simulations and observational techniques-all paramount for deciphering the nature of dark matter. The proceedings volume provides coverage of the most advanced stage of understanding dark matter in various new frameworks. The collection will be useful for graduate students, postdocs, and investigators interested in cutting-edge research on one of the biggest mysteries of our universe.

This book presents two important new findings. First, it demonstrates from first principles that turbulent heating offers an explanation for the non-adiabatic decay of proton temperature in solar wind. Until now, this was only proved with reduced or phenomenological models. Second, the book demonstrates that the two types of anisotropy of turbulent fluctuations that are observed in solar wind at 1AU originate not only from two distinct classes of conditions near the Sun but also from the imbalance in Alfven wave populations. These anisotropies do not affect the overall turbulent heating if we take into account the relation observed in solar wind between anisotropy and Alfven wave imbalance. In terms of the methods used to obtain these achievements, the author shows the need to find a very delicate balance between turbulent decay and expansion losses, so as to directly solve the magnetohydrodynamic equations, including the wind expansion effects.

This book provides a pedagogical introduction to the rapidly growing field of reheating after inflation. It begins with a brief review of the inflationary paradigm and a motivation for why the reheating of the universe is an integral part of inflationary cosmology. It then goes on to survey different aspects of reheating in a chronological manner, starting from the young, empty and cold universe at the end of inflation, and going all the way to the hot and thermal universe at the beginning of the Big Bang nucleosynthesis epoch. Different particle production mechanisms are considered with a focus on the non-perturbative excitation of scalar fields at the beginning of reheating (fermionic and vector fields are also discussed). This is followed by a review of the subsequent non-linear dynamical processes, such as soliton formation and relativistic turbulence. Various thermalization processes are also discussed. High energy physics embeddings of phenomenological models as well as observational implications of reheating such as gravitational waves generation and imprints on the cosmic microwave background are also covered.

This book is the first thorough and overdue biography of one of the giants of science in the twentieth century, Jan Hendrik Oort. His fundamental contributions had a lasting effect on the development of our insight and a profound influence on the international organization and cooperation in his area of science and on the efforts and contribution of his native country. This book aims at describing Oort's life and works in the context of the development of his branch of science and as a tribute to a great scientist in a broader sense. The astronomer Jan Hendrik Oort from the Netherlands was founder of studies of the structure and dynamics of the Milky Way Galaxy, initiator of radioastronomy and the European Southern Observatory, and an important contributor to many areas of astronomy, from the study of comets to the universe on the largest scales.

Modern computer power and high-precision observational data have greatly improved the reliability of meteoroid stream models. At present, scientific research calls for two kinds of models: precise ones for individual streams, and statistically averaged ones for Solar System dust distribution models. Thus, there is a wide field of study open to stream modellers. This brief describes step-by-step computer simulations of meteoroid stream formation and evolution. Detailed derivations of relevant formulae are given, along with plenty of helpful, digestible figures explaining the subtleties of the method. Each theoretical section ends with examples aimed to help readers practice and master the material. Most of the examples are based on the Geminid meteoroid stream model, which has been developed by the author in the last 30 years. The book is intended for researchers interested in meteor astronomy and mathematical modelling, and it is also accessible to physics and astrophysics students.

Cosmology and astroparticle physics have seen an avalanche of discoveries in the past decade (IceCube - high energy neutrinos, LIGO - gravitational waves, Fermi- gamma-ray telescope, Xenon-1T - dark matter detection, PLANCK- cosmic microwave radiation, EHT picture of black hole, SDSS -galaxy surveys), all of which require a multidisciplinary background for analyzing the phenomena. The arena for testing particle physics models is in the multimessenger astronomical observations and at the same time cosmology now requires a particle physics basis for explaining many phenomena. This book discusses the theoretical tools of particle physics and general relativity which are essential for understanding and correlating diverse astronomical observations.

Unlike most traditional introductory textbooks on relativity and cosmology that answer questions like "Does accelerated expansion pull our bodies apart?", "Does the presence of dark matter affect the classical tests of general relativity?" in a qualitative manner, the present text is intended as a foundation, enabling students to read and understand the textbooks and many of the scientific papers on the subject. And, above all, the readers are taught and encouraged to do their own calculations, check the numbers and answer the above and other questions regarding the most exciting discoveries and theoretical developments in general relativistic cosmology, which have occurred since the early 1980s. In comparison to these intellectual benefits the text is short. In fact, its brevity without neglect of scope or mathematical accessibility of key points is rather unique. The authors connect the necessary mathematical concepts and their reward, i.e. the understanding of an important piece of modern physics, along the shortest path. The unavoidable mathematical concepts and tools are presented in as straightforward manner as possible. Even though the mathematics is not very difficult, it certainly is beneficial to know some statistical thermodynamics as well as some quantum mechanics. Thus the text is suitable for the upper undergraduate curriculum.

These three lectures cover a certain aspect of complexity and black holes, namely the relation to the second law of thermodynamics. The first lecture describes the meaning of quantum complexity, the analogy between entropy and complexity, and the second law of complexity. Lecture two reviews the connection between the second law of complexity and the interior of black holes. Prof. L. Susskind discusses how firewalls are related to periods of non-increasing complexity which typically only occur after an exponentially long time. The final lecture is about the thermodynamics of complexity, and "uncomplexity" as a resource for doing computational work. The author explains the remarkable power of "one clean qubit," in both computational terms and in space-time terms. This book is intended for graduate students and researchers who want to take the first steps towards the mysteries of black holes and their complexity.

This Brief presents in a self-contained, non-technical and illustrative fashion the state-of-the-art results and techniques for the dynamics of extremal black holes. Extremal black holes are, roughly speaking, either maximally rotating or maximally charged. Astronomical observations suggest that near-extremal (stellar or supermassive) black holes are ubiquitous in the universe. The book presents various recently discovered characteristic phenomena (such as the horizon instability) that have enhanced our understanding of the dynamics of extremal black holes. The topics should be of interest to pure mathematicians, theoretical physicists and astronomers. This book provides common ground for communication between these scientific communities.

This book presents a study of the saturation of unstable f-modes (fundamental modes) due to low-order nonlinear mode coupling. Since their theoretical prediction in 1934, neutron stars have remained among the most challenging objects in the Universe. Gravitational waves emitted by unstable neutron star oscillations can be used to obtain information about their inner structure, that is, the equation of state of dense nuclear matter. After its initial growth phase, the instability is expected to saturate due to nonlinear effects. The saturation amplitude of the unstable mode determines the detectability of the generated gravitational-wave signal, but also affects the evolution of the neutron star. The study shows that the unstable (parent) mode resonantly couples to pairs of stable (daughter) modes, which drain the parent's energy and make it saturate via a mechanism called parametric resonance instability. Further, it calculates the saturation amplitude of the most unstable f-mode multipoles throughout their so-called instability windows.

This Festschrift dedicated to the 60th birth anniversary of Prof. Sandip K. Chakrabarti, a well-known Indian astrophysicist, presents a collection of contributions by about fifty scientists who work on diverse topics in contemporary astrophysics and space science including new and low-cost balloon borne experiments, planetary science, astrochemistry and the origin of life, ionospheric research and earthquake predictions, relativistic astrophysics around black holes, and finally, the observational signatures and radiative properties of compact objects. All the authors are well known scholars in their respective subject and are all PhD students of Prof. Sandip K. Chakrabarti. The book demonstrates a two-dimensional evolution of research areas triggered by Sandip Chakrabarti over the past few decades. The first dimension represents the evolution and diversification of Chakrabarti's own research in which new students were trained. A second dimension arises from the evolution of the research topics pursued by Chakrabarti's fifty odd doctoral students, many of whom have become renowned scientists in their own right, after starting with a certain subject under Chakrabarti and then migrating to completely new subjects with dexterity. The editors have compiled and edited the articles appropriately to some extent to suit the spirit of this Festschrift on the one hand and to keep balance in diverse topics on the other. Thus this volume also provides an overview for whosoever wishes to enter the important subjects of compact objects, astrochemistry, ionospheric science or space exploration in near space. New graduates, PhD scholars, teachers and researchers will benefit from this volume. Moreover it is a record of tremendous success of a school in a range of vast topics.

This didactic book uses a data-driven approach to connect measurements made by plasma instruments to the real world. This approach makes full use of the instruments' capability and examines the data at the most detailed level an experiment can provide. Students using this approach will learn what instruments can measure, and working with real-world data will pave their way to models consistent with these observations. While conceived as a teaching tool, the book contains a considerable amount of new information. It emphasizes recent results, such as particle measurements made from the Cluster ion experiment, explores the consequences of new discoveries, and evaluates new trends or techniques in the field. At the same time, the author ensures that the physical concepts used to interpret the data are general and widely applicable. The topics included help readers understand basic problems fundamental to space plasma physics. Some are appearing for the first time in a space physics textbook. Others present different perspectives and interpretations of old problems and models that were previously considered incontestable. This book is essential reading for graduate students in space plasma physics, and a useful reference for the broader astrophysics community.

This is one of the most important studies in decades on Johannes Kepler, among the towering figures in the history of astronomy. Drawing extensively on Kepler's correspondence and manuscripts, James Voelkel reveals that the strikingly unusual style of Kepler's magnum opus, "Astronomia nova" (1609), has been traditionally misinterpreted. Kepler laid forth the first two of his three laws of planetary motion in this work. Instead of a straightforward presentation of his results, however, he led readers on a wild goose chase, recounting the many errors and false starts he had experienced. This had long been deemed a ''confessional'' mirror of the daunting technical obstacles Kepler faced. As Voelkel amply demonstrates, it is not.

Voelkel argues that Kepler's style can be understood only in the context of the circumstances in which the book was written. Starting with Kepler's earliest writings, he traces the development of the astronomer's ideas of how the planets were moved by a force from the sun and how this could be expressed mathematically. And he shows how Kepler's once broader research program was diverted to a detailed examination of the motion of Mars. Above all, Voelkel shows that Kepler was well aware of the harsh reception his work would receive--both from Tycho Brahe's heirs and from contemporary astronomers; and how this led him to an avowedly rhetorical pseudo-historical presentation of his results. In treating Kepler at last as a figure in time and not as independent of it, this work will be welcomed by historians of science, astronomers, and historians.

These lecture notes are intended for starting PhD students in theoretical physics who have a working knowledge of General Relativity. The four topics covered are: Surface charges as conserved quantities in theories of gravity; Classical and holographic features of three-dimensional Einstein gravity; Asymptotically flat spacetimes in four dimensions: BMS group and memory effects; The Kerr black hole: properties at extremality and quasi-normal mode ringing. Each topic starts with historical foundations and points to a few modern research directions.

The articles included in this Volume represent a broad and highly qualified view on the present state of general relativity, quantum gravity, and their cosmological and astrophysical implications. As such, it may serve as a valuable source of knowledge and inspiration for experts in these fields, as well as an advanced source of information for young researchers. The occasion to gather together so many leading experts in the field was to celebrate the centenary of Einstein's stay in Prague in 1911-1912. It was in fact during his stay in Prague that Einstein started in earnest to develop his ideas about general relativity that fully developed in his paper in 1915. Approaching soon the centenary of his famous paper, this volume offers a precious overview of the path done by the scientific community in this intriguing and vibrant field in the last century, defining the challenges of the next 100 years. The content is divided into four broad parts: (i) Gravity and Prague, (ii) Classical General Relativity, (iii) Cosmology and Quantum Gravity, and (iv) Numerical Relativity and Relativistic Astrophysics.

This book is devoted to the study of certain integral representations for Neumann, Kapteyn, Schloemilch, Dini and Fourier series of Bessel and other special functions, such as Struve and von Lommel functions. The aim is also to find the coefficients of the Neumann and Kapteyn series, as well as closed-form expressions and summation formulas for the series of Bessel functions considered. Some integral representations are deduced using techniques from the theory of differential equations. The text is aimed at a mathematical audience, including graduate students and those in the scientific community who are interested in a new perspective on Fourier-Bessel series, and their manifold and polyvalent applications, mainly in general classical analysis, applied mathematics and mathematical physics.

The Finnish mathematician and astronomer Anders Johan Lexell (1740-1784) was a long-time close collaborator as well as the academic successor of Leonhard Euler at the Imperial Academy of Sciences in Saint Petersburg. Lexell was initially invited by Euler from his native town of Abo (Turku) in Finland to Saint Petersburg to assist in the mathematical processing of the astronomical data of the forthcoming transit of Venus of 1769. A few years later he became an ordinary member of the Academy. This is the first-ever full-length biography devoted to Lexell and his prolific scientific output. His rich correspondence especially from his grand tour to Germany, France and England reveals him as a lucid observer of the intellectual landscape of enlightened Europe. In the skies, a comet, a minor planet and a crater on the Moon named after Lexell also perpetuate his memory.

This book addresses a fascinating set of questions in theoretical physics which will both entertain and enlighten all students, teachers and researchers and other physics aficionados. These range from Newtonian mechanics to quantum field theory and cover several puzzling issues that do not appear in standard textbooks. Some topics cover conceptual conundrums, the solutions to which lead to surprising insights; some correct popular misconceptions in the textbook discussion of certain topics; others illustrate deep connections between apparently unconnected domains of theoretical physics; and a few provide remarkably simple derivations of results which are not often appreciated. The connoisseur of theoretical physics will enjoy a feast of pleasant surprises skilfully prepared by an internationally acclaimed theoretical physicist. Each topic is introduced with proper background discussion and special effort is taken to make the discussion self-contained, clear and comprehensible to anyone with an undergraduate education in physics.

This book is devoted to the problems that occur when attempting to understand and construct a concise representation of the original conditions, composition and dynamics of the evolution of the Earth-Moon system in the form in which it is seen today. This volume will perhaps contribute to a better understanding of what is necessary to research the dynamics of the Solar system.

A trio of editors [Professors from Austria, Germany and Israel] present Life on Earth and other Planetary Bodies. The contributors are from twenty various countries and present their research on life here as well as the possibility for extraterrestrial life. This volume covers concepts such as life's origin, hypothesis of Panspermia and of life possibility in the Cosmos. The topic of extraterrestrial life is currently 'hot' and the object of several congresses and conferences. While the diversity of "normal" biota is well known, life on the edge of the extremophiles is more limited and less distributed. Other subjects discussed are Astrobiology with the frozen worlds of Mars, Europa and Titan where extant or extinct microbial life may exist in subsurface oceans; conditions on icy Mars with its saline, alkaline, and liquid water which has been recently discovered; chances of habitable Earth-like [or the terrestrial analogues] exoplanets; and SETI's search for extraterrestrial Intelligence.

"The bubbles were swirling all around me, massaging my body. As I luxuriated in this fantastic bath, .... I gasped as I realized that these were miniature galaxies bringing the whole Cosmos into my bathtub..."

Alfie is back. And so are George and other characters of the author s previous book "Einstein s Enigma or Black Holes in My Bubble Bath." The present book, "Universe Unveiled - The Cosmos in My Bubble," can be considered a sequel to the previous one. It is nontechnical and descriptive. The scientific content is presented through the discussions between Alfie, the enlightened learner and George, professor of astrophysics. Fantasies, based on these discussions that cover scientific facts, are created by the magical bubble baths taken by Alfie.

The cosmic journey begins with ancient astronomers, such as Aristarchus and Ptolemy of Greece, Aryabhata from India, and Omar Khayyam from Persia.

The foundations of the cosmos, essentially the solar system, are laid by the great scientists like Copernicus, Tycho Brahe, Kepler, Galileo, and finally Isaac Newton.

This is followed by the realm of the stars with a description of stellar evolution and its three end-products, namely the white dwarfs, neutron stars, and black holes. The final phase of the cosmic journey begins with the large-scale structure of the Universe. From the early speculations of William Herschel, we move on to Harlow Shapley, the measurer of the Milky Way. The awesome vastness of the Universe is revealed by the remarkable observations of Edwin Hubble, while the strangest cosmic phenomenon of universal expansion is discovered by Hubble and his collaborator Milton Humason, the erstwhile mule driver. The theoretical basis of modern cosmology, the space-time picture of the general theory of relativity, is elucidated by Albert Einstein himself. The final chapters deal with the most modern developments such as the exact determination of the age of the Universe, dark matter, the acceleration of the universal expansion and dark energy.

"Universe Unveiled "blends accurate science with philosophy, drama, humour and fantasy to create an exciting cosmic journey that reads like a novel and educates as it entertains."

This book provides a completely revised and expanded version of the previous classic edition 'General Relativity and Relativistic Astrophysics'. In Part I the foundations of general relativity are thoroughly developed, while Part II is devoted to tests of general relativity and many of its applications. Binary pulsars - our best laboratories for general relativity - are studied in considerable detail. An introduction to gravitational lensing theory is included as well, so as to make the current literature on the subject accessible to readers. Considerable attention is devoted to the study of compact objects, especially to black holes. This includes a detailed derivation of the Kerr solution, Israel's proof of his uniqueness theorem, and a derivation of the basic laws of black hole physics. Part II ends with Witten's proof of the positive energy theorem, which is presented in detail, together with the required tools on spin structures and spinor analysis. In Part III, all of the differential geometric tools required are developed in detail. A great deal of effort went into refining and improving the text for the new edition. New material has been added, including a chapter on cosmology. The book addresses undergraduate and graduate students in physics, astrophysics and mathematics. It utilizes a very well structured approach, which should help it continue to be a standard work for a modern treatment of gravitational physics. The clear presentation of differential geometry also makes it useful for work on string theory and other fields of physics, classical as well as quantum.

This book gathers the lecture notes of the 100th Les Houches Summer School, which was held in July 2013. These lectures represent a comprehensive pedagogical survey of the frontier of theoretical and observational cosmology just after the release of the first cosmological results of the Planck mission. The Cosmic Microwave Background is discussed as a possible window on the still unknown laws of physics at very high energy and as a backlight for studying the late-time Universe. Other lectures highlight connections of fundamental physics with other areas of cosmology and astrophysics, the successes and fundamental puzzles of the inflationary paradigm of cosmic beginning, the themes of dark energy and dark matter, and the theoretical developments and observational probes that will shed light on these cosmic conundrums in the years to come.

Like everyone else, most amateur astronomers live busy lives. After a long day or work or looking after young children, the last thing you want as an observer is to have to lug out a large telescope and spend an hour getting it ready before it can be used. Maybe you are going on vacation somewhere in the countryside where there are sure to be dark skies, but you don't necessarily want astronomy to dominate the trip. Or suppose you are not quite committed to owning a large telescope, but curious enough to see what a smaller, portable setup can accomplish. These are times when a small "grab 'n' go" telescope, or even a pair of binoculars, is the ideal instrument. And this book can guide you in choosing and best utilizing that equipment. What makes a telescope fall into the "grab 'n' go" category? That's easy - speed of setting up, ease of use, and above all, portability. In Part I of this book, we survey the various types of equipment, including accessories and mounts, that are available, and what it is best for what kind of viewing. Part II is about using your grab 'n' go telescope to visit a wealth and wide variety of objects. There are chapters on solar, lunar and planetary observing, as well as descriptions of many deep sky objects, including double and variable stars, planetary, emission and reflection nebulae, open and globular clusters and distant galaxies. This ambitious text is dedicated to those who love to or - because of their limited time - must observe the sky at a moment's notice, whether from the comfort of a backyard or while on business or vacation far from home. Everything you need to know is here. So get started!.

The nascent commercial suborbital spaceflight industry will soon open the space frontier to commercial astronauts, payload specialists, scientists and of course, tourists. This book describes the tantalizing science opportunities to be offered when suborbital trips become routine within the next 12 to 18 months. It describes the difference in training and qualification necessary to become either a spaceflight participant or a fully-fledged commercial suborbital astronaut and it describes the vehicles this new class of astronauts will use.

Anticipation is on the rise for the new crop of commercial suborbital spaceships that will serve the scientific and educational market. These reusable rocket-propelled vehicles are expected to offer quick, routine and affordable access to the edge of space along with the capability to carry research and educational crew members. Yet to be demonstrated is the hoped-for flight rates of suborbital vehicles.

Quick turnaround of these craft is central to realizing the profit-making potential of repeated sojourns to suborbital heights. As this book outlines, vehicle builders still face rigorous shake-out schedules, flight safety hurdles as well as extensive trial-runs of their respective craft before suborbital space jaunts become commonplace. The book examines some of these cash and carry suborbital craft under development by such groups as Blue Origin, Masten Space Systems, Virgin Galactic and XCOR Aerospace and describes the hurdles the space industry is quickly overcoming en-route to the industry developing into a profitable economic entity.

Seedhouse also explains how the commercial suborbital spaceflight industry is planning and preparing for the challenges of marketing and financing and how it is marketing the hiring of astronauts. It examines the role of commercial operators as enablers accessing the suborbital frontier and how a partnership with governments and the private sector will eventually permanently integrate the free market s innovation of commercial suborbital space activities."