Classical Double Copy The New Connections In Gauge Theory And Gravity

Our current understanding of nature is in terms of matter that is acted on by forces. There are four fundamental forces, of which three are described by so-called gauge theories, a type of quantum field theory. The fourth force, gravity, is best described by general relativity, and our traditional ways of thinking about gauge theories and gravity look completely different from each other.In recent years, an exciting new correspondence called the 'double copy' has emerged, which suggests that the above theories may be much more closely related than previously thought. Inspired by previous work in string theory, it originated in the study of how particles interact, but has since been generalised to show that many gravitational quantities can be simply obtained by recycling simpler gauge theory results. This has significant practical applications — such as new calculational tools for astrophysics — but is also of conceptual importance, in suggesting that our current ways of thinking about fundamental physics are hiding a vast underlying structure.This book reviews our current theories of fundamental physics, before describing in detail how the double copy was discovered, how it can be applied to different types of object in gauge or gravity theory, and what its current and future applications are. No prior knowledge of quantum field theory or string theory is assumed, such that the book will be of interest to a broad audience of physicists and mathematicians.

Our current understanding of nature is in terms of matter that is acted on by forces. There are four fundamental forces, of which three are described by so-called gauge theories, a type of Quantum Field Theory. The fourth force, gravity, is best described by General Relativity, and our traditional ways of thinking about gauge theories and gravity look completely different from each other.In recent years, an exciting new correspondence called the 'double copy' has emerged, that suggests that the above theories may be much more closely related than previously thought. Inspired by previous work in string theory, it originated in the study of how particles interact, but has since been generalised to show that many gravitational quantities can be simply obtained by recycling simpler gauge theory results. This has significant practical applications -- such as new calculational tools for astrophysics -- but is also of conceptual importance, in suggesting that our current ways of thinking about fundamental physics are hiding a vast underlying structure.This book reviews our current theories of fundamental physics, before describing in detail how the double copy was discovered, how it can be applied to different types of object in gauge or gravity theory, and what its current and future applications are. No prior knowledge of quantum field theory or string theory is assumed, such that the book will be of interest to a broad audience of physicists and mathematicians.

This book presents a multidisciplinary guide to gauge theory and gravity, with chapters by the world’s leading theoretical physicists, mathematicians, historians and philosophers of science. The contributions from theoretical physics explore e.g. the consistency of the unification of gravitation and quantum theory, the underpinnings of experimental tests of gauge theory and its role in shedding light on the relationship between mathematics and physics. In turn, historians and philosophers of science assess the impact of Weyl’s view on the philosophy of science. Graduate students, lecturers and researchers in the fields of history of science, theoretical physics and philosophy of science will benefit from this book by learning about the role played by Weyl’s Raum-Zeit-Materie in shaping several modern research fields, and by gaining insights into the future prospects of gauge theory in both theoretical and experimental physics. Furthermore, the book facilitates interdisciplinary exchange and conceptual innovation in tackling fundamental questions about our deepest theories of physics. Chapter “Weyl’s Raum-Zeit-Materie and the Philosophy of Science” is available open access under a Creative Commons Attribution 4.0 International License via link.springer.com

The three volumes of the proceedings of MG15 give a broad view of all aspects of gravitational physics and astrophysics, from mathematical issues to recent observations and experiments. The scientific program of the meeting included 40 morning plenary talks over 6 days, 5 evening popular talks and nearly 100 parallel sessions on 71 topics spread over 4 afternoons. These proceedings are a representative sample of the very many oral and poster presentations made at the meeting.Part A contains plenary and review articles and the contributions from some parallel sessions, while Parts B and C consist of those from the remaining parallel sessions. The contents range from the mathematical foundations of classical and quantum gravitational theories including recent developments in string theory, to precision tests of general relativity including progress towards the detection of gravitational waves, and from supernova cosmology to relativistic astrophysics, including topics such as gamma ray bursts, black hole physics both in our galaxy and in active galactic nuclei in other galaxies, and neutron star, pulsar and white dwarf astrophysics. Parallel sessions touch on dark matter, neutrinos, X-ray sources, astrophysical black holes, neutron stars, white dwarfs, binary systems, radiative transfer, accretion disks, quasars, gamma ray bursts, supernovas, alternative gravitational theories, perturbations of collapsed objects, analog models, black hole thermodynamics, numerical relativity, gravitational lensing, large scale structure, observational cosmology, early universe models and cosmic microwave background anisotropies, inhomogeneous cosmology, inflation, global structure, singularities, chaos, Einstein-Maxwell systems, wormholes, exact solutions of Einstein's equations, gravitational waves, gravitational wave detectors and data analysis, precision gravitational measurements, quantum gravity and loop quantum gravity, quantum cosmology, strings and branes, self-gravitating systems, gamma ray astronomy, cosmic rays and the history of general relativity.

Gauge/gravity duality creates new links between quantum theory and gravity. It has led to new concepts in mathematics and physics, and provides new tools to solve problems in many areas of theoretical physics. This book is the first textbook on this important topic, enabling graduate students and researchers in string theory and particle, nuclear and condensed matter physics to get acquainted with the subject. Focusing on the fundamental aspects as well as on the applications, this textbook guides readers through a thorough explanation of the central concepts of gauge/gravity duality. For the AdS/CFT correspondence, it explains in detail how string theory provides the conjectured map. Generalisations to less symmetric cases of gauge/gravity duality and their applications are then presented, in particular to finite temperature and density, hydrodynamics, QCD-like theories, the quark-gluon plasma and condensed matter systems. The textbook features a large number of exercises, with solutions available online at www.cambridge.org/9781107010345.

In the course of the development of electromagnetic, weak and strong interactions, the concept of (internal) gauge invariance grew up and established itself as an unavoidable dynamical principle in particle physics. It is less known that the principle of equivalence, and the basic dynamical properties of the gravitational interaction can also be ex

By the end of the 1970s, it was clear that all the known forces of nature (including, in a sense, gravity) were examples of gauge theories, characterized by invariance under symmetry transformations chosen independently at each position and each time. These ideas culminated with the finding of the W and Z gauge bosons (and perhaps also the Higgs boson). This important book brings together the key papers in the history of gauge theories, including the discoveries of: the role of gauge transformations in the quantum theory of electrically charged particles in the 1920s; nonabelian gauge groups in the 1950s; vacuum symmetry-breaking in the 1960s; asymptotic freedom in the 1970s. A short introduction explains the significance of the papers, and the connections between them. Contents: Gauge Invariance in Electromagnetism; Non-Abelian Gauge Theories; Gravity as a Gauge Theory; Gauge Invariance and Superconductivity; Spontaneous Symmetry Breaking and Particle Physics; Gauge-Fixing in Non-Abelian Gauge Theories; Gauge Identities and Unitarity; Asymptotic Freedom; Monopoles and Vortex Lines; Non-Pertubative Approaches; Instantons and Vacuum Structure; Three-Dimensional Gauge Fields and Topological Actions; Gauge Theories and Mathematics. Readership: Graduate students, researchers and lecturers in mathematical, theoretical, quantum and high energy physics, as well as historians of science.

We describe some aspects of classical gauge theory from the perspective of connections on vector bundles. We begin by examining classical electromagnetism, and use it to motivate the development of gauge theory on vector bundles. If G is a Lie group, we review some of the theory of vector G-bundles, their associated principal G-bundles, and the related theory of connections. We then discuss the idea of gauge transformations on principal and vector G-bundles, and view electromagnetism as an example of an abelian gauge theory. We briefly review the action principle in order to describe non-abelian gauge theories such as the Yang-Mills equation. Finally, we present the main results from an article by John Baez entitled "Higher Yang-Mills Theory" where he attempts to abstract Yang-Mills theory using some concepts from category theory.

This is an introduction to the basic tools of mathematics needed to understand the relation between knot theory and quantum gravity. The book begins with a rapid course on manifolds and differential forms, emphasizing how these provide a proper language for formulating Maxwell's equations on arbitrary spacetimes. The authors then introduce vector bundles, connections and curvature in order to generalize Maxwell theory to the Yang-Mills equations. The relation of gauge theory to the newly discovered knot invariants such as the Jones polynomial is sketched. Riemannian geometry is then introduced in order to describe Einstein's equations of general relativity and show how an attempt to quantize gravity leads to interesting applications of knot theory.

This book evolved out of some one hundred lectures given by twenty experts at a special instructional conference sponsored by the University Grants Commis sion, India. It is pedagogical in style and self-contained in several interrelated areas of physics which have become extremely important in present-day theoretical research. The articles begin with an introduction to general relativity and cosmology as well as particle physics and quantum field theory. This is followed by reviews of the standard gauge models of high-energy physics, renormalization group and grand unified theories. The concluding parts of the book comprise discussions in current research topics such as problems of the early universe, quantum cosmology and the new directions towards a unification of gravitation with other forces. In addition, special concise treatments of mathematical topics of direct relevance are also included. The content of the book was carefully worked out for the mutual education of students and research workers in general relativity and particle physics. This ambitious programe consequently necessitated the involvement of a number of different authors. However, care has been taken to ensure that the material meshes into a unified, cogent and readable book. We hope that the book will serve to initiate and guide a student in these different areas of investigation starting from first principles and leading to the exciting current research problems of an interdisciplinary nature in the context of the origin and structure of the universe.