An Introduction to Gauge Theories

Introduction. The Feynman Path Integral. Towards a Field Theory. Equations of Motion, Symmetries, and Ward's Identity. The Electromagnetic Field. Fermion Fields. Scattering Processes and the S-Matrix. Perturbative Green's Functions in Λϕ4. S-Matrix Feynman Diagrams in Λϕ4. Quantum Electrodynamics. Renormalization of QED. Applications of QED. Renormalization Group of QED. Quantizing a Non-Abelian Theory. The Beta Function in QCD. Unitarity and Ghosts. Effective Constants at High Energy and Ideas about Grand Unification. Limits on the Mass of the Higgs Boson. The Weak Muon Anomaly. Effective Potential and Naturalness. Appendix A: Transition Amplitude Calculation. Appendix B: Connected Diagrams. Appendix C: Lorentz Invariance and One Particle States. Appendix D: Reduction Formulae. Appendix E: Integrals. Appendix F: Beta Functions. Bibliography.

Biography

Nicola Cabibbo (1935-2010) was professor of Theoretical Physics and Elementary Particle Phyiscs at the Rome Universities La Sapienza and Tor Vergata, and held research and teaching positions in prestigious institutions such as Harvard University, the Institute for Advanced Studies, Princeton, CERN, Geneva, University of California at Berkeley and Universite Paris VI. In 1962, Cabibbo discovered the phenomenon of quark mixing, described by a new natural constant, the Cabibbo angle, measured with great accuracy in semileptonic weak decays of hadrons. According to a recent analysis, Cabibbo's paper on quark mixing was the most influential article published in the journals of the American Physical Society during 1893-2003. In the 1980s, Cabibbo provided important momentum to the applications of numerical techniques to theoretical physics, notably the gauge theories of strong interactions, promoting and leading the development of the family of APE (Array Processor Experiment) supercomputers. He served as a member of a number of learned societies: Accademia Nazionale dei Lincei and Accademia delle Scienze di Torino, in Italy, National Academy of Science and American Association for Art and Sciences, in the USA, and Accademia Pontificia delle Scienze, which he chaired from 1993. An internationally reputed science manager, Cabibbo was President of Istituto Nazionale di Fisica Nucleare (INFN) and of Ente Nazionale per le Nuove Tecnologie per Energia e Ambiente (ENEA). He was the recipient of the J.J. Sakurai Prize (APS), the Medaglia Matteucci (Accademia Nazionale dei XL), the Dirac Medal, (ICTP Trieste), and the Benjamin Franklin Medal.

Luciano Maiani is emeritus professor of theoretical physics at the University of Rome, "La Sapienza", and author of more than two hundred scientic publications on the theoretical physics of elementary particles. Together with S. Glashow and J. Iliopoulos, Maiani made the prediction of a new family of particles, those with "charm", which form an essential part of the unifed theory of the weak and electromagnetic forces. He has been president of the Italian Institute for Nuclear Physics (INFN), director-general of CERN in Geneva and president of the Italian National Council for Research (CNR). Has promoted the development of the Virgo Observatory for gravitational wave detection, the neutrino beam from CERN to Gran Sasso and at CERN has directed the crucial phases of the construction of the Large Hadron Collider (LHC). He has taught and worked in numerous foreign institutes. He was head of the theoretical physics department at the University of Rome, "La Sapienza", from 1976 to 1984 and held the chair of theoretical physics from 1984 to 2011. He is a member of the Italian Lincean Academy and a fellow of the American Physical Society. For his scientific work, he has been awarded the J. J. Sakurai Prize, the Enrico Fermi Prize, the Dirac Medal, the High Energy and Particle Physics Prize of EPS and the Bruno Pontecorvo Prize.

Omar Benhar is an INFN research director and teaches gauge theories at the University of Rome, "La Sapienza". He has worked extensively in the United States as a visiting professor, at the University of Illinois and Old Dominion University, and was an associate scientist at the Thomas Jeerson National Accelerator Facility. Since 2013, he has served as an adjunct professor at the Centre for Neutrino Physics of Virginia Polytechnic Institute and State University. He is the author of more than a hundred scientific papers on the theory of many-particle systems, the structure of compact stars and electroweak interactions of nuclei.

"This book on gauge theories completes a trilogy on the foundations of the Standard Theory of the fundamental interactions, but is fully self-contained. It combines the depth and conceptual accuracy expected from key contributors to the field with an effective pedagogical approach, tested over several decades of courses. The mathematical formalism is never overwhelming, and the reader is guided through the concepts and techniques of quantum gauge theories along a path always driven by physics, including recent developments on the Higgs boson. This book is a great legacy of the `Rome School’ for students, teachers and researchers in particle physics, not only theorists but also curious experimentalists."
—Fabio Zwirner, University of Padua

"Introduction to Gauge Theories is authored by leading contributors to the Standard Model of Particle Physic (SM): Nicola Cabibbo (the proponent of quark mixing angles, whose extension led to the Cabibbo-Kobayashi-Maskawa matrix); Luciano Maiani (one of the fathers of the so-called GIM mechanism which led to the prediction of the quark charm); and Omar Benhar (a well-known expert in many-body physics) and it constitutes a most welcome addition to the literature. A must-have in any physics library, this book is highly original, centring on deep problems of quantum field theory, and consistently well-motivated by experimental phenomena. The symmetries of nature are the guiding principle, illuminating the presentation of the concept of renormalisation and its applications in gauge theories, from a thorough and pedagogical analysis of Quantum Electrodynamics, to the exploration of Quantum Chromodynamics and the SM, including the role of the Higgs field, and beyond.
Everybody can find some food for thought here: from the graduate student to the most hardened researcher. This book is full of physical insights and is highly recommended."
—Belén Gavela, Professor of Theoretical Physics at