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

A sweeping account of the century of experimentation that confirmed Einstein's general theory of relativity, bringing to life the science and scientists at the origins of relativity, the development of radio telescopes, the discovery of black holes and quasars, and the still unresolved place of gravity in quantum theory. Albert Einstein did nothing of note on May 29, 1919, yet that is when he became immortal. On that day, astronomer Arthur Eddington and his team observed a solar eclipse and found something extraordinary: gravity bends light, just as Einstein predicted. The finding confirmed the theory of general relativity, fundamentally changing our understanding of space and time. A century later, another group of astronomers is performing a similar experiment on a much larger scale. The Event Horizon Telescope, a globe-spanning array of radio dishes, is examining space surrounding Sagittarius A*, the supermassive black hole at the center of the Milky Way. As Ron Cowen recounts, the foremost goal of the experiment is to determine whether Einstein was right on the details. Gravity lies at the heart of what we don't know about quantum mechanics, but tantalizing possibilities for deeper insight are offered by black holes. By observing starlight wrapping around Sagittarius A*, the telescope will not only provide the first direct view of an event horizon-a black hole's point of no return-but will also enable scientists to test Einstein's theory under the most extreme conditions. Gravity's Century shows how we got from the pivotal observations of the 1919 eclipse to the Event Horizon Telescope, and what is at stake today. Breaking down the physics in clear and approachable language, Cowen makes vivid how the quest to understand gravity is really the quest to comprehend the universe.

E = mc2 and the Periodic Table . . .
RELATIVISTIC EFFECTS IN CHEMISTRY
This century's most famous equation, Einstein's special theory of relativity, transformed our comprehension of the nature of time and matter. Today, making use of the theory in a relativistic analysis of heavy molecules, that is, computing the properties and nature of electrons, is the work of chemists intent on exploring the mysteries of minute particles.
The first work of its kind, Relativistic Effects in Chemistry details the computational and analytical methods used in studying the relativistic effects in chemical bonding as well as the spectroscopic properties of molecules containing very heavy atoms. The first of two independent volumes, Part A: Theory and Techniques describes the basic techniques of relativistic quantum chemistry. Its systematic five-part format begins with a detailed exposition of Einstein's special theory of relativity, the significance of relativity in chemistry, and the nature of relativistic effects, especially with molecules containing both main group atoms and transition metal atoms.
Chapter 3 discusses the fundamentals of relativistic quantum mechanics starting from the Klein-Gordon equation through such advanced constructs as the Breit-Pauli and Dirac multielectron Hamiltonian. Modern computational techniques, of importance with problems involving very heavy molecules, are outlined in Chapter 4. These include the relativistic effective core potentials, ab initio CASSCF, CI, and RCI techniques. Chapter 5 describes relativistic symmetry using the double group symmetry of molecules and the classification of relativistic electronic states and is of special importanceto chemists or spectroscopists interested in computing or analyzing electronic states of molecules containing very heavy atoms.
An exceptional introduction to one of chemistry's foremost analytical techniques, Relativistic Effects in Chemistry is also evidence of the still unending reverberations of Einstein's revolutionary theory.

This richly annotated facsimile edition of "The Foundation of General Relativity" introduces a new generation of readers to Albert Einstein's theory of gravitation. Written in 1915, this remarkable document is a watershed in the history of physics and an enduring testament to the elegance and precision of Einstein's thought. Presented here is a beautiful facsimile of Einstein's original handwritten manuscript, along with its English translation and an insightful page-by-page commentary that places the work in historical and scientific context. Hanoch Gutfreund and Jurgen Renn's concise introduction traces Einstein's intellectual odyssey from special to general relativity, and their essay "The Charm of a Manuscript" provides a delightful meditation on the varied afterlife of Einstein's text. Featuring a foreword by John Stachel, this handsome edition also includes a biographical glossary of the figures discussed in the book, a comprehensive bibliography, suggestions for further reading, and numerous photos and illustrations throughout.

As we humans have expanded our horizons to see things vastly smaller, faster, larger, and farther than ever before, we have been forced to confront preconceptions born of the human experience and create wholly new ways of looking at the world around us. The theories of relativity and quantum physics were developed out of this need and have provided us with phenomenal, mind-twisting insights into the strange and exciting reality show of our universe.

"Relativity and Quantum Physics For Beginners" is an entertaining and accessible introduction to the bizarre concepts that fueled the scientific revolution of the 20th century and led to amazing advances in our understanding of the universe.

Einstein's general theory of relativity - currently our best theory of gravity - is important not only to specialists, but to a much wider group of physicists. This short textbook on general relativity and gravitation offers students glimpses of the vast landscape of science connected to general relativity. It incorporates some of the latest research in the field. The book is aimed at readers with a broad range of interests in physics, from cosmology, to gravitational radiation, to high energy physics, to condensed matter theory. The pedagogical approach is "physics first": readers move very quickly to the calculation of observational predictions, and only return to the mathematical foundations after the physics is established. In addition to the "standard" topics covered by most introductory textbooks, it contains short introductions to more advanced topics: for instance, why field equations are second order, how to treat gravitational energy, and what is required for a Hamiltonian formulation of general relativity. A concluding chapter discusses directions for further study, from mathematical relativity, to experimental tests, to quantum gravity. This is an introductory text, but it has also been written as a jumping-off point for readers who plan to study more specialized topics.

Self-organization of matter is observed in every context and on all scales, from the nanoscale of quantum fields and subatomic particles to the macroscale of galaxy superclusters. This book analyzes the wide range of patterns of organization present in nature, highlighting their similarities rather than their differences. This unconventional approach results in an illuminating read which should be part of any Physics student's background.

This book employs computer simulations of 'artificial' Universes to investigate the properties of two popular alternatives to the standard candidates for dark matter (DM) and dark energy (DE). It confronts the predictions of theoretical models with observations using a sophisticated semi-analytic model of galaxy formation. Understanding the nature of dark matter (DM) and dark energy (DE) are two of the most central problems in modern cosmology. While their important role in the evolution of the Universe has been well established-namely, that DM serves as the building blocks of galaxies, and that DE accelerates the expansion of the Universe-their true nature remains elusive. In the first half, the authors consider 'sterile neutrino' DM, motivated by recent claims that these particles may have finally been detected. Using sophisticated models of galaxy formation, the authors find that future observations of the high redshift Universe and faint dwarf galaxies in the Local Group can place strong constraints on the sterile neutrino scenario. In the second half, the authors propose and test novel numerical algorithms for simulating Universes with a 'modified' theory of gravity, as an alternative explanation to accelerated expansion. The authors' techniques improve the efficiency of these simulations by more than a factor of 20 compared to previous methods, inviting the readers into a new era for precision cosmological tests of gravity.

When predictions of Einstein's theory of General Relativity are compared against observations of our Universe, a huge inconsistency is found. The most popular fix for this inconsistency is to "invent" around 94% of the content of the universe: dark matter and dark energy. The dark energy is some exotic substance responsible for the apparent observed acceleration of the Universe. Another fix is to modify the theory of gravity: it is entirely plausible that Einstein's theory of General Relativity breaks down on cosmological scales, just as Newton's theory of gravity breaks down in the extreme gravitational field of the Sun. There are many alternative theories of gravity, each with the aim of describing observations of our Universe where General Relativity fails. Whether it is dark energy or some modified theory of gravity, it is clear that there is some "dark sector" in the Universe. In this thesis the author constructs a unifying framework for understanding the observational impact of general classes of dark sector theories, by formulating equations of state for the dark sector perturbations.

After completing the final version of his general theory of relativity in November 1915, Albert Einstein wrote a book about relativity for a popular audience. His intention was "to give an exact insight into the theory of relativity to those readers who, from a general scientific and philosophical point of view, are interested in the theory, but who are not conversant with the mathematical apparatus of theoretical physics." The book remains one of the most lucid explanations of the special and general theories ever written. In the early 1920s alone, it was translated into ten languages, and fifteen editions in the original German appeared over the course of Einstein's lifetime. This new edition of Einstein's celebrated book features an authoritative English translation of the text along with an introduction and a reading companion by Hanoch Gutfreund and Jurgen Renn that examines the evolution of Einstein's thinking and casts his ideas in a broader present-day context. A special chapter explores the history of and the stories behind the early foreign-language editions in light of the reception of relativity in different countries. This edition also includes a survey of the introductions from those editions, covers from selected early editions, a letter from Walther Rathenau to Einstein discussing the book, and a revealing sample from Einstein's handwritten manuscript. Published on the hundredth anniversary of general relativity, this handsome edition of Einstein's famous book places the work in historical and intellectual context while providing invaluable insight into one of the greatest scientific minds of all time.

Einstein's Revolution is a textbook on relativity written from a historical-methodological point of view. It can be used as an account of Einstein's physical theory even if the reader has no sympathy with the author's philosophical standpoint, or it can be read for the author's philosophical argument, without the reader having to follow all the details of the physics. The work challenges a distinction made by the Vienna Circle an still influential today: the distinction between "the context of discovery" and "the context of justification." According to the traditional view, the context of discovery calls for no rational reconstruction and belongs, in effect, to psychology, while only latter is subject to a proper logic of appraisal. Against these theses, Zahar shows that there is a logic of discovery and that it plays an important role in the appraisal of theories.

Einstein said that the most incomprehensible thing about the universe is that it is comprehensible. But was he right? Can the quantum theory of fields and Einstein's general theory of relativity, the two most accurate and successful theories in all of physics, be united into a single quantum theory of gravity? Can quantum and cosmos ever be combined? In The Nature of Space and Time, two of the world's most famous physicists--Stephen Hawking (A Brief History of Time) and Roger Penrose (The Road to Reality)--debate these questions. The authors outline how their positions have further diverged on a number of key issues, including the spatial geometry of the universe, inflationary versus cyclic theories of the cosmos, and the black-hole information-loss paradox. Though much progress has been made, Hawking and Penrose stress that physicists still have further to go in their quest for a quantum theory of gravity.

During the past two decades the gravitational asymptotic safety scenario has undergone a major transition from an exotic possibility to a serious contender for a realistic theory of quantum gravity. It aims at a mathematically consistent quantum description of the gravitational interaction and the geometry of spacetime within the realm of quantum field theory, which keeps its predictive power at the highest energies. This volume provides a self-contained pedagogical introduction to asymptotic safety, and introduces the functional renormalization group techniques used in its investigation, along with the requisite computational techniques. The foundational chapters are followed by an accessible summary of the results obtained so far. It is the first detailed exposition of asymptotic safety, providing a unique introduction to quantum gravity and it assumes no previous familiarity with the renormalization group. It serves as an important resource for both practising researchers and graduate students entering this maturing field.

Relativity has much to offer for a well-rounded education. Yet books on relativity either assume a strong background in physics and math, aimed at advanced physics students, or, alternatively, offer a broad description with little intellectual challenge. This book bridges the gap. It aims at readers with essentially no physics or math background, who still find it rewarding to think rigorously. The book takes a "thinking tools" approach, by first making readers comfortable with a new thinking tool and then applying it to learn more about how nature works. By the end of the book, readers will have collected a versatile toolbox and will be comfortable using the tools to think about and really understand the intriguing phenomena they may have only heard about, including the twin paradox, black holes, and time travel. End-of-chapter exercises span a range of difficulty, allowing adventurous readers to stretch their understanding further as desired. Students who have studied, or are studying, relativity at a more mathematical level will also find the book useful for a more conceptual understanding.

This book presents a high-level study of cosmology with interacting dark energy and no additional fields. It is known that dark energy is not necessarily uniform when other sources of gravity are present: interaction with matter leads to its variation in space and time. The present text studies the cosmological implications of this circumstance by analyzing cosmological models in which the dark energy density interacts with matter and thus changes with the time. The book also includes a translation of a seminal article about the remarkable life and work of E.B. Gliner, the first person to suggest the concept of dark energy in 1965.

The 20th century gave us two great theories of physics: the general theory of relativity, which describes the behaviour of things on a very large scale, including the entire Universe; and quantum theory, which describes the behaviour of things on a very small scale, the sub-atomic world. The refusal of the Universe to reveal an equation that combines these two great ideas has caused some people to doubt our whole understanding of physics. In this landmark new book, popular science master John Gribbin tells the dramatic story of the quest that has led us to discover the true age of the Universe (13.8 billion years) and the stars (just a little bit younger). This discovery, Gribbin argues, is one of humankind's greatest achievements and shows us that physics is on the right track to finding the 'Theory of Everything'. 13.8 provides an eye-opening look at this cutting-edge area of modern cosmology and physics, and tells the compelling story of what modern science has achieved - and what it can still achieve.

A pithy yet deep introduction to Einstein's general theory of relativity Of the four fundamental forces of nature, gravity might be the least understood and yet the one with which we are most intimate. On Gravity combines depth with accessibility to take us on a compelling tour of Einstein's general theory of relativity. A. Zee begins with the discovery of gravity waves, then explains how gravity can be understood in comparison to other classical field theories, presents the idea of curved spacetime, and explores black holes and Hawking radiation. Zee travels as far as the theory reaches, leaving us with tantalizing hints of the unknown, from the intransigence of quantum gravity to the mysteries of dark matter. Infused with Zee's signature warmth and fresh style, On Gravity opens a unique pathway to comprehending relativity, gravity, spacetime, and the workings of the universe.

Following the approach of Lev Landau and Evgenii Lifshitz, this book introduces the theory of special and general relativity with the Lagrangian formalism and the principle of least action. This method allows the complete theory to be constructed starting from a small number of assumptions, and is the most natural approach in modern theoretical physics. The book begins by reviewing Newtonian mechanics and Newtonian gravity with the Lagrangian formalism and the principle of least action, and then moves to special and general relativity. Most calculations are presented step by step, as is done on the board in class. The book covers recent advances in gravitational wave astronomy and provides a general overview of current lines of research in gravity. It also includes numerous examples and problems in each chapter.

This work is a detailed study of both the theoretical and phenomenological consequences of a massive graviton, within the ghost-free theory of massive gravity, the de Rham-Gabadadze-Tolley (dRGT) theory. Its aim is to test the physical viability of the theory. It begins by putting constraints on the parameters of the theory in the decoupling limit based on purely theoretical grounds, like classical stability in the cosmological evolution of self-accelerating and degravitating solutions. The author then constructs a proxy theory to massive gravity from the decoupling limit resulting in non-minimally coupled scalar-tensor interactions as an example of a subclass of Horndeski theories. Lastly, she addresses the natural question of whether the parameters introduced in the dRGT theory are subject to strong renormalization by quantum loops and shows how the non-renormalization theorem protects the graviton mass from quantum corrections. Beyond the decoupling limit the quantum corrections are found to be proportional to the graviton mass, proving its technical naturalness.

Tjonnie Li's thesis covers two applications of Gravitational Wave astronomy: tests of General Relativity in the strong-field regime and cosmological measurements. The first part of the thesis focuses on the so-called TIGER, i.e. Test Infrastructure for General Relativity, an innovative Bayesian framework for performing hypothesis tests of modified gravity using ground-based GW data. After developing the framework, Li simulates a variety of General Relativity deviations and demonstrates the ability of the aforementioned TIGER to measure them. The advantages of the method are nicely shown and compared to other, less generic methods. Given the extraordinary implications that would result from any measured deviation from General Relativity, it is extremely important that a rigorous statistical approach for supporting these results would be in place before the first Gravitational Wave detections begin. In developing TIGER, Tjonnie Li shows a large amount of creativity and originality, and his contribution is an important step in the direction of a possible discovery of a deviation (if any) from General Relativity. In another section, Li's thesis deals with cosmology, describing an exploratory study where the possibility of cosmological parameters measurement through gravitational wave compact binary coalescence signals associated with electromagnetic counterparts is evaluated. In particular, the study explores the capabilities of the future Einstein Telescope observatory. Although of very long term-only applicability, this is again a thorough investigation, nicely put in the context of the current and the future observational cosmology.

In early April 1911 Albert Einstein arrived in Prague to become full professor of theoretical physics at the German part of Charles University. It was there, for the first time, that he concentrated primarily on the problem of gravitation. Before he left Prague in July 1912 he had submitted the paper "Relativitat und Gravitation: Erwiderung auf eine Bemerkung von M. Abraham" in which he remarkably anticipated what a future theory of gravity should look like. At the occasion of the Einstein-in-Prague centenary an international meeting was organized under a title inspired by Einstein's last paper from the Prague period: "Relativity and Gravitation, 100 Years after Einstein in Prague". The main topics of the conference included: classical relativity, numerical relativity, relativistic astrophysics and cosmology, quantum gravity, experimental aspects of gravitation and conceptual and historical issues. The conference attracted over 200 scientists from 31 countries, among them a number of leading experts in the field of general relativity and its applications. This volume includes abstracts of the plenary talks and full texts of contributed talks and articles based on the posters presented at the conference. These describe primarily original results of the authors. Full texts of the plenary talks are included in the volume "General Relativity, Cosmology and Astrophysics--Perspectives 100 Years after Einstein in Prague", eds. J. Bicak and T. Ledvinka, published also by Springer Verlag.

Over the course of the last century it has become clear that both elementary particle physics and relativity theories are based on the notion of symmetries. These symmetries become manifest in that the "laws of nature" are invariant under spacetime transformations and/or gauge transformations. The consequences of these symmetries were analyzed as early as in 1918 by Emmy Noether on the level of action functionals. Her work did not receive due recognition for nearly half a century, but can today be understood as a recurring theme in classical mechanics, electrodynamics and special relativity, Yang-Mills type quantum field theories, and in general relativity. As a matter of fact, as shown in this monograph, many aspects of physics can be derived solely from symmetry considerations. This substantiates the statement of E.P. Wigner "... if we knew all the laws of nature, or the ultimate Law of nature, the invariance properties of these laws would not furnish us new information." Thanks to Wigner we now also understand the implications of quantum physics and symmetry considerations: Poincare invariance dictates both the characteristic properties of particles (mass, spin, ...) and the wave equations of spin 0, 1/2, 1, ... objects. Further, the work of C.N. Yang and R. Mills reveals the consequences of internal symmetries as exemplified in the symmetry group of elementary particle physics. Given this pivotal role of symmetries it is thus not surprising that current research in fundamental physics is to a great degree motivated and inspired by considerations of symmetry. The treatment of symmetries in this monograph ranges from classical physics to now well-established theories of fundamental interactions, to the latest research on unified theories and quantum gravity.

The effective theory of quantum gravity coupled to models of particle physics is being probed by cutting edge experiments in both high energy physics (searches for extra dimensions) and cosmology (testing models of inflation). This thesis derives new bounds that may be placed on these models both theoretically and experimentally. In models of extra dimensions, the internal consistency of the theories at high energies are investigated via perturbative unitarity bounds. Similarly it is shown that recent models of Higgs inflation suffer from a breakdown of perturbative unitarity during the inflationary period. In addition, the thesis uses the latest LHC data to derive the first ever experimental bound on the size of the Higgs boson's non-minimal coupling to gravity.

The search for gravitational radiation with optical interferometers is gaining momentum worldwide. Beside the VIRGO and GEO gravitational wave observatories in Europe and the two LIGOs in the United States, which have operated successfully during the past decade, further observatories are being completed (KAGRA in Japan) or planned (ILIGO in India). The sensitivity of the current observatories, although spectacular, has not allowed direct discovery of gravitational waves. The advanced detectors (Advanced LIGO and Advanced Virgo) at present in the development phase will improve sensitivity by a factor of 10, probing the universe up to 200 Mpc for signal from inspiraling binary compact stars. This book covers all experimental aspects of the search for gravitational radiation with optical interferometers. Every facet of the technological development underlying the evolution of advanced interferometers is thoroughly described, from configuration to optics and coatings and from thermal compensation to suspensions and controls. All key ingredients of an advanced detector are covered, including the solutions implemented in first-generation detectors, their limitations, and how to overcome them. Each issue is addressed with special reference to the solution adopted for Advanced VIRGO but constant attention is also paid to other strategies, in particular those chosen for Advanced LIGO.