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Title: Introduction to gauge theories of the strong, weak, and electromagnetic interactions

The plan of these notes is as follows. Chapter 1 is devoted to a brief evocative review of current beliefs and prejudices that form the context for the discussion to follow. The idea of Gauge Invariance is introduced in Chapter 2, and the connection between conservation laws and symmetries of the Lagrangian is recalled. Non-Abelian gauge field theories are constructed in Chapter 3, by analogy with the familiar case of electromagnetism. The Yang-Mills theory based upon isospin symmetry is constructed explicitly, and the generalization is made to other gauge groups. Chapter 4 is concerned with spontaneous symmetry breaking and the phenomena that occur in the presence or absence of local gauge symmetries. The existence of massless scalar fields (Goldstone particles) and their metamorphosis by means of the Higgs mechanism are illustrated by simple examples. The Weinberg-Salam model is presented in Chapter 5, and a brief resume of applications to experiment is given. Quantum Chromodynamics, the gauge theory of colored quarks and gluons, is developed in Chapter 6. Asymptotic freedom is derived schematically, and a few simple applications of perturbative QCD ae exhibited. Details of the conjectured confinement mechanism are omitted. The strategy of grand unified theories of the strong, weak,more » and electromagnetic interactions is laid out in Chapter 7. Some properties and consequences of the minimal unifying group SU(5) are presented, and the gauge hierarchy problem is introduced in passing. The final chapter contains an essay on the current outlook: aspirations, unanswered questions, and bold scenarios.« less
Authors:
Publication Date:
OSTI Identifier:
6498121
Report Number(s):
FERMILAB-Conf-80/64THY
TRN: 81-010901
DOE Contract Number:
AC02-76CH03000
Resource Type:
Technical Report
Research Org:
Fermi National Accelerator Lab., Batavia, IL (USA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; UNIFIED GAUGE MODELS; LECTURES; LEPTONS; QUANTUM CHROMODYNAMICS; QUARK MODEL; QUARKS; SU-5 GROUPS; SYMMETRY BREAKING; WEINBERG LEPTON MODEL; COMPOSITE MODELS; DOCUMENT TYPES; ELEMENTARY PARTICLES; FERMIONS; FIELD THEORIES; LIE GROUPS; MATHEMATICAL MODELS; PARTICLE MODELS; POSTULATED PARTICLES; QUANTUM FIELD THEORY; SU GROUPS; SYMMETRY GROUPS 645200* -- High Energy Physics-- Particle Interactions & Properties-Theoretical