Based on a two-semester course held at the University of Heidelberg, Germany, this book provides a solid basis for postgraduate students wishing to obtain a more profound understanding of the foundations of Quantum Field Theory. The book covers a wide spectrum of topics ranging from traditional operator and modern path integral methods, to different regularization and renormalization methods, asymptotic behavior of Green functions, a particular view on the Renormalization Group, and spontaneous symmetry breaking in effective potentials. Much effort has been made to present the material in a transparent, detailed and structured way, which should help the reader to follow the material.

Causality is central to understanding the mechanisms of nature: some event "A" is the cause of another event "B". Surprisingly, causality does not follow this simple rule in quantum physics: due to to quantum superposition we might be led to believe that "A causes B" and that "B causes A". This idea is not only important to the foundations of physics but also leads to practical advantages: a quantum circuit with such indefinite causality performs computationally better than one with definite causality. This thesis provides one of the first comprehensive introductions to quantum causality, and presents a number of advances. It provides an extension and generalization of a framework that enables us to study causality within quantum mechanics, thereby setting the stage for the rest of the work. This comprises: mathematical tools to define causality in terms of probabilities; computational tools to prove indefinite causality in an experiment; means to experimentally test particular causal structures; and finally an algorithm that detects the exact causal structure in an quantum experiment.

(Hard Cover Edition): The Universe is big, cold, violent, and doomed. What could be reassuring about this? Welcome on a voyage through a universe of personal relevance, potential, and purpose. Your voyage will cross the blank space on the map between science and spirit. Can these words even appear at peace together? Surely our intellect and our heart must remain locked in combat for our loyalty; surely intelligence precludes faith and education exorcises belief. Entering the temple, church, or mosque you have to check your brain at the door; entering the laboratory or university you have to check your soul at the door. Invoking quantum mechanics, the holographic universe, relativity, string theory, M theory, multiple dimensions, alternative universes, dark matter, dark energy, and virtual particles, Part I of The Reassuring Universe unveils the surprising spiritual potential and personal relevance of modern science. Does modern science make room for spirit and soul, even God and eternal life? Part II examines repeating patterns in evolution of the universe, life, and humanity. Is humanity, and are we as individuals, still subject to these evolving patterns? Do our most personal joys and grief reflect the role of our life within those universal patterns? Can we even find hints of the meaning of life and purpose of life in the weaving together of the universal patterns of science and the deepest experiences of heart? Part III reveals a seamless Oneness and nonduality in the structure of the universe as described by science. That science-based nonduality is then rendered deeply and personally relevant for your daily life. Your tour of The Reassuring Universe unfolds in full color through photographs of the cosmos and images of the human condition. The Reassuring Universe invokes quotes from a broad spectrum of traditions, with Brian Greene (author of The Elegant Universe) and the Bhagavad-Gita sharing space with Buddhist, Muslim, and Christian sources.

Providing a systematic introduction to the techniques which are fundamental to quantum field theory, this book pays special attention to the use of these techniques in a wide variety of areas, including ordinary quantum mechanics, quantum mechanics in the second-quantized formulation, relativistic quantum field theory, Euclidean field theory, quantum statistics at finite temperature, and the classical statistics of nonideal gas and spin systems. The extended chapter on variational methods and functional Legendre transformations contains completely original material.

Perturbation theory is a powerful tool for solving a wide variety of problems in applied mathematics, a tool particularly useful in quantum mechanics and chemistry. Although most books on these subjects include a section offering an overview of perturbation theory, few, if any, take a practical approach that addresses its actual implementation Introduction to Perturbation Theory in Quantum Mechanics does. It collects into a single source most of the techniques for applying the theory to the solution of particular problems. Concentrating on problems that allow exact analytical solutions of the perturbation equations, the book resorts to numerical results only when necessary to illustrate and complement important features of the theory. The author also compares different methods by applying them to the same models so that readers clearly understand why one technique may be preferred over another. Demonstrating the application of similar techniques in quantum and classical mechanics, Introduction to Perturbation Theory in Quantum Mechanics reveals the underlying mathematics in seemingly different problems. It includes many illustrative examples that facilitate the understanding of theoretical concepts, and provides a source of ideas for many original research projects.

This book comprises the lectures of a two-semester course on quantum field theory, presented in a quite informal and personal manner. The course starts with relativistic one-particle systems, and develops the basics of quantum field theory with an analysis on the representations of the Poincare group. Canonical quantization is carried out for scalar, fermion, Abelian and non-Abelian gauge theories. Covariant quantization of gauge theories is also carried out with a detailed description of the BRST symmetry. The Higgs phenomenon and the standard model of electroweak interactions are also developed systematically. Regularization and (BPHZ) renormalization of field theories as well as gauge theories are discussed in detail, leading to a derivation of the renormalization group equation. In addition, two chapters - one on the Dirac quantization of constrained systems and another on discrete symmetries - are included for completeness, although these are not covered in the two-semester course.This second edition includes two new chapters, one on Nielsen identities and the other on basics of global supersymmetry. It also includes two appendices, one on fermions in arbitrary dimensions and the other on gauge invariant potentials and the Fock-Schwinger gauge.

The book contains seven refereed research papers on locally compact quantum groups and groupoids by leading experts in the respective fields. These contributions are based on talks presented on the occasion of the meeting between mathematicians and theoretical physicists held in Strasbourg from February 21 to February 23, 2002. Topics covered are: various constructions of locally compact quantum groups and their multiplicative unitaries; duality theory for locally compact quantum groups; combinatorial quantization of flat connections associated with SL(2,c); quantum groupoids, especially coming from Depth 2 Extensions of von Neumann algebras, C*-algebras and Rings. Many mathematical results are motivated by problems in theoretical physics. Historical remarks set the results presented in perspective. Directed at research mathematicians and theoretical physicists as well as graduate students, the volume will give an overview of a field of research in which great progress has been achieved in the last few years, with new ties to many other areas of mathematics and physics.

Get First-Hand Insight from a Contributor to the Standard Model of Particle Physics Written by an award-winning former director-general of CERN and one of the world's leading experts on particle physics, Electroweak Interactions explores the concepts that led to unification of the weak and electromagnetic interactions. It provides the fundamental elements of the theory of compact Lie groups and their representations, enabling a basic understanding of the role of flavor symmetry in particle physics. Understand Conceptual Elements of the Theory of Elementary Particles The book begins with the identification of the weak hadronic current with the isotopic spin current, Yang-Mills theory, and the first electroweak theory of Glashow. It discusses spontaneous breaking of a global symmetry and a local symmetry, covering the Goldstone theorem, Brout-Englert-Higgs mechanism, and the theory of Weinberg and Salam. The author then describes the theory of quarks, quark mixing, the Cabibbo angle, the Glashow-Iliopoulos-Maiani (GIM) mechanism, the theory of Kobayashi and Maskawa, six quark flavors, and CP violation. Delve into Experimental Tests and Unresolved Problems The author goes on to explore some phenomenological topics, such as neutral current interactions of neutrinos and CP violation in the neutral K-meson system. He also highlights how flavor-changing neutral current processes have emerged as probes to reveal the presence of new phenomena at energies not yet accessible with particle accelerators. The book concludes with an explanation of the expected properties of the Higgs boson and the methods adopted for its search. The predictions are also compared with relevant experimental results. View the author's first book in this collection: Relativistic Quantum Mechanics: An Introduction to Relativistic Quantum Fields.

Despite its long history and stunning experimental successes, the mathematical foundation of perturbative quantum field theory is still a subject of ongoing research. This book aims at presenting some of the most recent advances in the field, and at reflecting the diversity of approaches and tools invented and currently employed. Both leading experts and comparative newcomers to the field present their latest findings, helping readers to gain a better understanding of not only quantum but also classical field theories. Though the book offers a valuable resource for mathematicians and physicists alike, the focus is more on mathematical developments. This volume consists of four parts: The first Part covers local aspects of perturbative quantum field theory, with an emphasis on the axiomatization of the algebra behind the operator product expansion. The second Part highlights Chern-Simons gauge theories, while the third examines (semi-)classical field theories. In closing, Part 4 addresses factorization homology and factorization algebras.

This book summarizes recent developments in the research area of quantum gravity phenomenology. A series of short and nontechnical essays lays out the prospects of various experimental possibilities and their current status. Finding observational evidence for the quantization of space-time was long thought impossible. In the last decade however, new experimental design and technological advances have changed the research landscape and opened new perspectives on quantum gravity. Formerly dominated by purely theoretical constructions, quantum gravity now has a lively phenomenology to offer. From high precision measurements using macroscopic quantum oscillators to new analysis methods of the cosmic microwave background, no stone is being left unturned in the experimental search for quantum gravity. This book sheds new light on the connection of astroparticle physics with the quantum gravity problem. Gravitational waves and their detection are covered. It illustrates findings from the interconnection between general relativity, black holes and Planck stars. Finally, the return on investment in quantum-gravitation research is illuminated. The book is intended for graduate students and researchers entering the field.

This thesis offers a fascinating journey through various non-perturbative aspects of Conformal Theories, in particular focusing on the Conformal Bootstrap Programme and its extensions to theories with various degrees of symmetry. Because of the preeminent role of Conformal Theories in Nature, as well as the great generality of the results here obtained, this analysis directly applies to many different areas of research. The content of this thesis is certainly relevant for the physics community as a whole and this relevance is well motivated and discussed along the various chapters of this work. The work is self-contained and starts with an original introduction to conformal theories, defects in such theories and how they lead to constraints on data and an extension of the bootstrap programme. This situation is often realized by critical systems with impurities, topological insulators, or - in the high-energy context - by Wilson and 't Hooft operators. The thesis continues with original research results of the author, including supersymmetric extensions. These results may be relevant non only in the high energy physics context - where supersymmetry is required for the theory to be consistent - but also for condensed matter systems that enjoy supersymmetry emergence at long distances.

Almost ?fteen years later, and there is little change in our motivation. Mathem- ical physics of quantum systems remains a lively subject of intrinsic interest with numerous applications, both actual and potential. Intheprefacetothe?rsteditionwehavedescribedtheoriginofthisbookrooted at the beginning in a course of lectures. With this fact in mind, we were naturally pleased to learn that the volume was used as a course text in many points of the world and we gladly accepted the o?er ofSpringer Verlag which inherited the rights from our original publisher, to consider preparation of a second edition. It was our ambition to bring the reader close to the places where real life dwells, and therefore this edition had to be more than a corrected printing. The ?eld is developing rapidly and since the ?rst edition various new subjects have appeared; as a couple of examples let us mention quantum computing or the major progress in theinvestigationofrandomSchr] odingeroperators.Thereare, however, goodsources intheliteraturewherethereadercanlearnabouttheseandothernewdevelopments.

This book introduces mathematicians, physicists, and philosophers to a new, coherent approach to theory and interpretation of quantum physics, in which classical and quantum thinking live peacefully side by side and jointly fertilize the intuition. The formal, mathematical core of quantum physics is cleanly separated from the interpretation issues. The book demonstrates that the universe can be rationally and objectively understood from the smallest to the largest levels of modeling. The thermal interpretation featured in this book succeeds without any change in the theory. It involves one radical step, the reinterpretation of an assumption that was virtually never questioned before - the traditional eigenvalue link between theory and observation is replaced by a q-expectation link: Objective properties are given by q-expectations of products of quantum fields and what is computable from these. Averaging over macroscopic spacetime regions produces macroscopic quantities with negligible uncertainty, and leads to classical physics. - Reflects the actual practice of quantum physics. - Models the quantum-classical interface through coherent spaces. - Interprets both quantum mechanics and quantum field theory. - Eliminates probability and measurement from the foundations. - Proposes a novel solution of the measurement problem.

The present monograph is devoted to the principal problems of quantum mechanics and is based on the conception first stated in my course on 'Fundamentals of Quantum Mechanics'. The scope and purpose of the above course did not allow some principal questions to be brought out as fully as they deserved, and besides, some important points were only very recently developed to a sufficient extent. This refers especially to the analysis of the action of the measuring instrument, whose dual role as an analyser of a quantum ensemble and as a detector of individual events was insufficiently elucidated. The reader will find that the present monograph is concerned more with theoretical physics than with philosophy. However, I have never separated Weltanschauung from science (and particularly theoretical physics) so that the philosophical implications are also discussed, justi fying publication in the philosophical series. In conclusion, I should like to thank the publisher and the translator, whose initiative and effort have made it possible for the book to reach the English-speaking reader."

Some major developments of physics in the last three decades are addressed by highly qualified specialists in different specific fields. They include renormalization problems in QFT, vacuum energy fluctuations and the Casimir effect in different configurations, and a wealth of applications. A number of closely related issues are also considered. The cosmological applications of these theories play a crucial role and are at the very heart of the book; in particular, the possibility to explain in a unified way the whole history of the evolution of the Universe: from primordial inflation to the present day accelerated expansion. Further, a description of the mathematical background underlying many of the physical theories considered above is provided. This includes the uses of zeta functions in physics, as in the regularization problems in QFT already mentioned, specifically in curved space-time, and in Casimir problems as.

Starting from basic principles, the book covers a wide variety of topics, ranging from Heisenberg, Schroedinger, second quantization, density matrix and path integral formulations of quantum mechanics, to applications that are (or will be) corner stones of present and future technologies. The emphasis is on spin waves, quantum information, recent tests of quantum physics and decoherence. The book provides a large amount of information without unbalancing the flow of the main ideas by laborious detail.

The present volume has its source in the CAP-CRM summer school on "Particles and Fields" that was held in Banff in the summer of 1994. Over the years, the Division of Theoretical Physics of the Canadian Associa- tion of Physicists (CAP) has regularly sponsored such schools on various theoretical and experimental topics. In 1994, the Centre de Recherches Mathematiques (CRM) lent its support to the event. This institute, located in Montreal, is one of Canada's national research centers in the mathe- matical sciences. Its mandate includes the organization of scientific events across Canada and since 1994 the CRM has been holding a yearly summer school in Banff as part of its thematic program. The summer school, whose lectures are collected here, has thus become a tradition. The focus of the school was integrable theories, matrix models, statistical systems, field theory and its applications to condensed matter physics, as well as certain aspects of algebra, geometry, and topology. This covers some of the most significant advances in modern theoretical physics. The present volume updates and expands these lectures and reflects the high pedagogical level of the school. The first chapter by E. Corrigan describes some of the remarkable fea- tures of the integrable Toda field theories which are associated with affine Dynkin diagrams. The second chapter by J. Feldman, H. Knorrer, D. Leh- mann, and E.

Quantum electrodynamics (QED) is the branch of relativistic quantum field theory that deals specifically with the interactions between charged particles. It is widely used to solve problems in many areas of physics, such as elementary particles, atomic and molecular systems, and solid state physics. This accessible text, Basics of Quantum Electrodynamics, supplies a solid foundation in this dynamic area of physics, making a direct connection to the concepts of quantum mechanics familiar to the advanced undergraduate student. Chapters cover the general theory of free fields and the quantization of the scalar, electromagnetic, and spinorial fields, which prepares readers for understanding field interactions. The authors describe the general theory of field interactions, introducing the scattering matrix and the Feynman-Dyson graphs. They then discuss divergence-free second-order processes, such as Compton and Moller scattering, followed by divergent second-order processes, which cover vacuum polarization and mass and charge renormalization. Providing a modern, informative textbook, this volume illustrates the intimate connection between quantum mechanics and QED in two basic steps: the quantization of free fields, followed by the theory of their interactions. The text contains solved problems to facilitate the application of the theory, as well as a useful appendix on the theory of distributions. The step-by-step description of the quantization of various fields and the clear presentation of the most important interaction processes in QED make this textbook a useful guide for those studying physics at both the graduate and undergraduate level, as well as a reference for teachers and researchers in the field.

In 1905, Albert Einstein offered a revolutionary theory--special relativity--to explain some of the most troubling problems in current physics concerning electromagnetism and motion. Soon afterwards, Hermann Minkowski recast special relativity essentially as a new geometric structure for spacetime. These ideas are the subject of the first part of the book. The second part develops the main implications of Einstein's general relativity as a theory of gravity rooted in the differential geometry of surfaces. The author explores the way an individual observer views the world and how a pair of observers collaborate to gain objective knowledge of the world. To encompass both the general and special theory, he uses the geometry of spacetime as the unifying theme of the book. To read it, one needs only a first course in linear algebra and multivariable calculus and familiarity with the physical applications of calculus.

This book presents research contributions focussing on the introduction of contemporary physics topics - mainly, but not exclusively, quantum physics - into high school currciula. Despite the important advances and discoveries in quantum physics and relativity which have revolutionized our views of nature and our everyday lives, the presence of these topics in high school physics education is still lacking. In this book physics education researchers report on the teaching and learning of quantum physics from different perspectives and discuss the design and use of different pedagogical approaches and educational pathways. There is still much debate as to what content is appropriate at high school level as well what pedagogical approaches and strategies should be adopted to support student learning. Currently there is a greater focus on how to teach modern physics at the high school level rather than classical physics. However, teachers still lack experience and availability of appropriate teaching and learning materials to support the coherent integration of Quantum Physics in high school curricula. All of the 19 papers presented in this book discuss innovative approaches for enhancing physics education in schools.

The purpose of this book is to give a systematic pedagogical exposition of the quantitative analysis of Wilson lines and gauge-invariant correlation functions in quantum chromodynamics. Using techniques from the previous volume (Wilson Lines in Quantum Field Theory, 2014), an ab initio methodology is developed and practical tools for its implementation are presented. Emphasis is put on the implications of gauge invariance and path-dependence properties of transverse-momentum dependent parton density functions. The latter are associated with the QCD factorization approach to semi-inclusive hadronic processes, studied at currently operating and planned experimental facilities. Contents: Introduction Particle Number Operators in Quantum Mechanics and in Quantum Field Theory Geometry of Quantum Field Theories Basics of Wilson Lines in QCD Gauge-Invariant Parton Densities Simplifying Wilson Line Calculations Brief Literature Guide Conventions and Reference Formulae Integrations Bibliography Index

This book explores critical phenomena in highly correlated quantum matter. Specifically, quantum antiferromagnets, magnon Bose condensates, and systems exhibiting deconfined quantum criticality are considered. The book's main achievement is the incorporation of both quantum and statistical fluctuations into a quantum field theoretic treatment of critical phenomena. This yields significant new insights into an abundance of problems, positions them in a much more general context, and offers an unprecedented power to analyze experimental and numerical data and predict new effects. Further, a major result and overarching theme is the exploration of the scale-dependent coupling constant - an effect known in quantum chromodynamics as "asymptotic freedom." The book provides the first analysis to reveal asymptotic freedom in the quantum magnetism context, and discusses many other manifestations. Another significant result concerns the development of a consistent theoretical framework that resolves a long-standing inconsistency in the theory of Bose condensation. Using the approach developed here, two new universality classes are subsequently identified. A final major result addresses the exotic scenario of deconfined quantum criticality. Within this framework, the book predicts the Bose condensation of particles with half-integer spin - the first- ever made in this regard. In closing, a smoking gun criterion to test for this exotic condensate is established.

This textbook presents the basics of philosophy that are necessary for the student and researcher in science in order to better understand scientific work. The approach is not historical but formative: tools for semantical analysis, ontology of science, epistemology, and scientific ethics are presented in a formal and direct way. The book has two parts: one with the general theory and a second part with application to some problems such as the interpretation of quantum mechanics, the nature of mathematics, and the ontology of spacetime. The book addresses questions such as "What is meaning?", "What is truth?", "What are truth criteria in science?", "What is a theory?", "What is a model?" "What is a datum?", "What is information?", "What does it mean to understand something?", "What is space?", "What is time?", "How are these concepts articulated in science?" "What are values?" "What are the limits of science?", and many more. The philosophical views presented are "scientific" in the sense that they are informed by current science, they are relevant for scientific research, and the method adopted uses the hypothetical-deductive approach that is characteristic of science. The results and conclusions, as any scientific conclusion, are open to revision in the light of future advances. Hence, this philosophical approach opposes to dogmatic philosophy. Supported by end-of-chapter summaries and a list of special symbols used, the material will be of interest for students and researchers in both science and philosophy. The second part will appeal to physicists and mathematicians.