In order to outline possible future directions in galaxy research, this book wants to be a short stopover, a moment of self-reflection of the past century of achievements in this area. Since the pioneering years of galaxy research in the early 20th century, the research on galaxies has seen a relentless advance directly connected to the parallel exponential growth of new technologies. Through a series of interviews with distinguished astronomers the editors provide a snapshot of the achievements obtained in understanding galaxies. While many initial questions about their nature have been addressed, many are still open and require new efforts to achieve a solution. The discussions may reveal paradigms worthwhile revisiting. With the help of some of those scientists who have contributed to it, the editors sketch the history of this scientific journey and ask them for inspirations for future directions of galaxy research.

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.

In this thought-provoking book Kuppers, an internationally renowned physicist, philosopher and theoretical biologist, addresses a number of science's deepest questions: Can physics advance to the origin of all things and explain the unique phenomena of life, time and history? Are there unsolvable enigmas of the world? How did life originate? Is language a general phenomenon of Nature? What is time? Is it possible to express the history of the world in formulae? Where is science leading us? These and other provocative questions essential for a deeper understanding of the world are treated here in a refreshing and stimulating manner.

Tackling galactic evolution in a truly novel way, this outstanding thesis statistically explores the long-term evolution of galaxies, using recent theoretical breakthroughs that explicitly account for their self-gravity. While treating processes statistically, the astrophysical differences on each scale are also captured. As the archetype of self-amplified diffusion, the implications of the thesis go far beyond astrophysics. Gravity is the driving force in galaxies, from their far outskirts to their innermost cores. These "extended kinetic theories" offer unique physical insights into the competing dynamical processes at play, complementing N-body approaches. The thesis successfully gauges the role of nature and nurture in establishing the galaxies' observed properties, using kinetic equations to capture both sources of fluctuations. Further, it shows how secular diffusion shapes the phase space structure of cold stellar disks. The thesis subsequently determines the characteristic timescales and examines the signatures of secular evolution in this framework on two scales: from the kinetic evolution in galactic disks and their thickening via giant molecular clouds; all the way down to the stellar resonant relaxation of the central cluster and its black hole.

This White Paper describes the state of astrobiology in Europe today and its relation to the European society at large. With contributions from authors in twenty countries and over thirty scientific institutions worldwide, the document illustrates the societal implications of astrobiology and the positive contribution that astrobiology can make to European society. The White paper has two main objectives: 1. It recommends the establishment of a European Astrobiology Institute (EAI) as an answer to a series of challenges relating to astrobiology but also European research, education and the society at large. 2. It also acknowledges the societal implications of astrobiology, and thus the role of the social sciences and humanities in optimizing the positive contribution that astrobiology can make to the lives of the people of Europe and the challenges they face. This book is recommended reading for science policy makers, the interested public, and the astrobiology community.

This prize-winning Ph.D. thesis by Chris Harrison adopts a multi-faceted approach to address the lack of decisive observational evidence, utilising large observational data sets from several world-leading telescopes. Developing several novel observational techniques, Harrison demonstrated that energetic winds driven by Active Galactic Nuclei (AGN) are found in a large number of galaxies, with properties in agreement with model predictions. One of the key unsolved problems in astrophysics is understanding the influence of AGN, the sites of growing supermassive black holes, on the evolution of galaxies. Leading theoretical models predict that AGN drive energetic winds into galaxies, regulating the formation of stars. However, until now, we have lacked the decisive observational evidence to confirm or refute these key predictions. Careful selection of targets allowed Harrison, to reliably place these detailed observations into the context of the overall galaxy population. However, in disagreement with the model predictions, Harrison showed that AGN have little global effect on star formation in galaxies. Theoretical models are now left with the challenge of explaining these results.

Scientific Cosmology and International Orders shows how scientific ideas have transformed international politics since 1550. Allan argues that cosmological concepts arising from Western science made possible the shift from a sixteenth-century order premised upon divine providence to the present order centred on economic growth. As states and other international associations used scientific ideas to solve problems, they slowly reconfigured ideas about how the world works, humanity's place in the universe, and the meaning of progress. The book demonstrates the rise of scientific ideas across three cases: natural philosophy in balance of power politics, 1550-1815; geology and Darwinism in British colonial policy and international colonial orders, 1860-1950; and cybernetic-systems thinking and economics in the World Bank and American liberal order, 1945-2015. Together, the cases trace the emergence of economic growth as a central end of states from its origins in colonial doctrines of development and balance of power thinking about improvement.

This thesis presents several significant new results that shed light on two major puzzles of modern cosmology: the nature of inflation, the very early phase of the universe that is thought to have given rise to the large-scale structures that we observe today; and that of the current accelerated expansion. In particular, it develops a clean method for characterizing linear cosmological perturbations for general theories where gravity is modified and/or affected by a new component, called dark energy, responsible for the accelerated expansion. It proposes a new extension to what were long thought to be the most general scalar field theories devoid of instabilities, and demonstrates the robustness of the relation between the energy scale of inflation and the predicted amplitude of gravitational waves. Finally, it consolidates a set of consistency relations between correlation functions of the cosmological density field and investigates the phenomenological consequences of their potential violation. Presented in a clear, succinct and rigorous style, each of these original results is both profound and important and will leave a deep mark on the field.

In this book, leading theorists present new contributions and reviews addressing longstanding challenges and ongoing progress in spacetime physics. In the anniversary year of Einstein's General Theory of Relativity, developed 100 years ago, this collection reflects the subsequent and continuing fruitful development of spacetime theories. The volume is published in honour of Carl Brans on the occasion of his 80th birthday. Carl H. Brans, who also contributes personally, is a creative and independent researcher and one of the founders of the scalar-tensor theory, also known as Jordan-Brans-Dicke theory. In the present book, much space is devoted to scalar-tensor theories. Since the beginning of the 1990s, Brans has worked on new models of spacetime, collectively known as exotic smoothness, a field largely established by him. In this Festschrift, one finds an outstanding and unique collection of articles about exotic smoothness. Also featured are Bell's inequality and Mach's principle. Personal memories and historical aspects round off the collection.

This book comprises expository articles on different aspects of gravitation and cosmology that are aimed at graduate students. The topics discussed are of contemporary interest assuming only an elementary introduction to gravitation and cosmology. The presentations are to a certain extent pedagogical in nature, and the material developed is not usually found in sufficient detail in recent textbooks in these areas.

"If you buy just one guide...you won't do better than this" BBC Sky at Night Magazine "I will continue to enjoy 'Philip's Stargazing' as the months go by" Helen Sharman, Astronaut "Very useful indeed" Chris Lintott, Sky at Night presenter Now including the top astronomical places to visit, star festivals and the latest on star parties in Britain and Ireland, the new 2023 edition is totally up-to-date for exploring the wonder of the night skies, month-by-month and day-by-day. Whether you're a seasoned astronomer or just starting out, Philip's Stargazing 2023 is the only book you'll need. Compiled by experts and specially designed for easy and daily use, Stargazing 2023 acts as a handily illustrated and comprehensive companion. - 12 updated sky charts for year-round astronomical discovery - Month-to-Month information. Daily Moon Phase Calendar, highlighting special lunar events throughout the year - Planet Watch for ideal viewing days in 2023 - The best places to experience Dark Skies, along with the latest on Star Festivals and Star Parties - Top places to visit for astronomical insights - Expert advice and insight throughout from internationally renowned Prof Nigel Henbest - The latest on electronic telescopes from expert Robin Scagell - Complete calendar of major astronomical events, including the Top 20 Sky Sights of 2023 - Jargon Buster, explaining common or confusing terms - The planets' movements explained from solar and lunar eclipses to meteor showers and comets

Of value to the general scientific public, this is the first book in the world scientific literature devoted to the Casimir effect. This topic has important applications in the fields of elementary particle physics, statistical physics, quantum field theory, gravitation and cosmology.

This book contains the elaborated and updated versions of the 24 lectures given at the 43rd Saas-Fee Advanced Course. Written by four eminent scientists in the field, the book reviews the physical processes related to star formation, starting from cosmological down to galactic scales. It presents a detailed description of the interstellar medium and its link with the star formation. And it describes the main numerical computational techniques designed to solve the equations governing self-gravitating fluids used for modelling of galactic and extra-galactic systems. This book provides a unique framework which is needed to develop and improve the simulation techniques designed for understanding the formation and evolution of galaxies. Presented in an accessible manner it contains the present day state of knowledge of the field. It serves as an entry point and key reference to students and researchers in astronomy, cosmology, and physics.

Delineating the huge strides taken in cosmology in the past ten years, this much-anticipated second edition of Malcolm Longair's highly appreciated textbook has been extensively and thoroughly updated. It tells the story of modern astrophysical cosmology from the perspective of one of its most important and fundamental problems - how did the galaxies come about? Longair uses this approach to introduce the whole of what may be called "classical cosmology". What's more, he describes how the study of the origin of galaxies and larger-scale structures in the Universe has provided us with direct information about the physics of the very early Universe.

Modified gravity theories have been a main focus of theoretical cosmology research in the past decade or so, and have been quickly developing into a mature research field that attracts attention, interest and effort from both theoretical and observational cosmologists. To be prepared for fully exploiting the future observational data, and to provide a guidance for people who are new to this field, it is useful to have a comprehensive review to summarise the current state of knowledge and to foresee the future developments.This book presents expert reviews on different topics in the field, which are then coordinated and organised in a self-consistent and self-contained manner. It is suitable for graduate students and researchers interested in the frontier research of gravity theories.

This book sheds new light on topological defects in widely differing systems, using the Velocity-Dependent One-Scale Model to better understand their evolution. Topological defects - cosmic strings, monopoles, domain walls or others - necessarily form at cosmological (and condensed matter) phase transitions. If they are stable and long-lived they will be fossil relics of higher-energy physics. Understanding their behaviour and consequences is a key part of any serious attempt to understand the universe, and this requires modelling their evolution. The velocity-dependent one-scale model is the only fully quantitative model of defect network evolution, and the canonical model in the field. This book provides a review of the model, explaining its physical content and describing its broad range of applicability.

This thesis addresses two of the central processes which underpin the formation of galaxies: the formation of stars and the injection of energy into the interstellar medium from supernovae, called feedback. In her work Claudia Lagos has completely overhauled the treatment of these processes in simulations of galaxy formation. Her thesis makes two major breakthroughs, and represents the first major steps forward in these areas in more than a decade. Her work has enabled, for the first time, predictions to be made which can be compared against new observations which probe the neutral gas content of galaxies, opening up a completely novel way to constrain the models. The treatment of feedback from supernovae, and how this removes material from the interstellar medium, is also likely to have a lasting impact on the field. Claudia Lagos Ph.D. thesis was nominated by the Institute for Computational Cosmology at Durham University as an outstanding Ph.D. thesis 2012.

In the first chapters the author describes how our knowledge of the position of Earth in space and time has developed, thanks to the work of many generations of astronomers and physicists. He discusses how our position in the Galaxy was discovered, and how in 1929, Hubble uncovered the fact that the Universe is expanding, leading to the picture of the Big Bang. He then explains how astronomers have found that the laws of physics that were discovered here on Earth and in the Solar System (the laws of mechanics, gravity, atomic physics, electromagnetism, etc.) are valid throughout the Universe. This is illustrated by the fact that all matter in the Universe consists of atoms of the same chemical elements that we know on Earth. This unity is all the more surprising when one realizes that in the original Big Bang theory, different parts of the Universe could never have communicated with each other. It then is a mystery how they could have shared the same physical laws. This problem was solved by the introduction of the idea of inflation, a phase of extremely rapid expansion of the Universe during the first fraction of a second following the Big Bang. The author explains how the unity of the Universe finds its origin in the Big Bang prior to inflation. The book addresses the many fundamental questions about the Universe and its contents from the perspective of the Big Bang: the formation of structure in the Universe, the questions of the mysterious dark matter and dark energy, the possibilities of other Universes (the Multiverse) and of the existence of intelligent life elsewhere in the Universe.

This book gives an accessible account of the history of the Universe; not only what happened, but why it happened. An author of textbooks on the early Universe and inflation, David Lyth now explains both cosmology and the underlying physics to the general reader. The book includes a detailed account of the almost imperceptible structure in the early Universe, and its probable origin as a quantum fluctuation during an early epoch known as the epoch of inflation. It also explains how that early structure is visible now in the cosmic microwave radiation which is our main source of information about the early Universe, and how it gave rise to galaxies and stars. The main text of the book assumes no knowledge of mathematics or physics so that it is accessible to everybody, while an appendix contains more advanced material. As a result the book will be useful for a wide spectrum of readers, including high-school students, undergraduates, postgraduates and professional physicists working in areas other than cosmology. It will also serve as "additional reading" for university courses in general astronomy, astrophysics or cosmology itself.

This work deals with the search for signatures of non-Gaussianities in the cosmic microwave background (CMB). Probing Gaussianity in the CMB addresses one of the key questions in modern cosmology because it allows us to discriminate between different models of inflation, and thus concerns a fundamental part of the standard cosmological model. The basic goal here is to adapt complementary methods stemming from the field of complexity science to CMB data analysis. Two key concepts, namely the method of surrogates and estimators for local scaling properties, are applied to CMB data analysis. All results show strong non-Gaussianities and pronounced asymmetries. The consistency of the full sky and cut sky results shows convincingly for the first time that the influence of the Galactic plane is not responsible for these deviations from Gaussianity and isotropy. The findings seriously call into question predictions of isotropic cosmologies based on the widely accepted single field slow roll inflation model.

Astronomer Peter Linde takes the reader through the story of the search for extraterrestrial life in a captivating and thought-provoking way, specifically addressing the new research that is currently devoted towards discovering other planets with life. He discusses the methods used to detect possible signals from other civilizations and the ways that the space sciences are changing as a result of this new field. "Are we alone?" is a mystery that has forever fascinated mankind, gaining momentum by scientists since the 1995 discovery of the existence of exoplanets began to inspire new ways of thinking in astronomy. Here, Linde tries to answer many philosophical questions that derive from this area of research: Is humanity facing a change of paradigm, that we are not unique as intelligent beings? Is it possible to communicate with others out there, and even if we can-should we?

This thesis explores advanced Bayesian statistical methods for extracting key information for cosmological model selection, parameter inference and forecasting from astrophysical observations. Bayesian model selection provides a measure of how good models in a set are relative to each other - but what if the best model is missing and not included in the set? Bayesian Doubt is an approach which addresses this problem and seeks to deliver an absolute rather than a relative measure of how good a model is. Supernovae type Ia were the first astrophysical observations to indicate the late time acceleration of the Universe - this work presents a detailed Bayesian Hierarchical Model to infer the cosmological parameters (in particular dark energy) from observations of these supernovae type Ia.

As new discoveries complicate the scientific picture of the universe, the evolving theories about the nature of space and time and the origins and fate of the universe threaten to become overwhelming. Enter David Seargent. Continuing the author's series of books popularizing strange astronomy facts and knowledge, Weird Universe explains the bizarre, complicated terrain of modern cosmology for lay readers. From exploring some of the strange consequences of the theories of special and general relativity, to probing time dilation and the twin and mother-and-baby "paradoxes" and the theory that the universe can be mathematically considered as a hologram, all of the latest findings and conjectures are clearly described in non-technical language. The development of quantum physics and the more recent developments of string and M-theory are looked at, in addition to several hypotheses that have not won wide acceptance from the scientific community, such as modified gravity. Enter the wonderfully weird world of these theories and gain a new appreciation for the latest findings in cosmological research.