PREFACENOTATION1 HISTORICAL INTRODUCTION 1.1 Relativistic Wave Mechanics 1.2 The Birth of Quantum Fiedld Theory 1.3 The Problem of Infinities Bibliography References2 RELATIVISTIC QUANTUM MECHANICS 2.1 Quantum Mechanics 2.2 Symmetries 2.3 Quantum Lorentz Transformations 2.4 The Poincare Algebra 2.5 One-Particle States 2.6 Space Inversion and Time-Reversal 2.7 Projective Representations AppendixA The Symmetry Representation Theorem AppendixB Group Operators and Homotopy Classes AppendixC Inversions and Degenerate Multiplets Problems References3 SCATTERING THEORY 3.1 In and Out States 3.2 The S-matrix 3.3 Symmetries of the S-Matrix 3.4 Rates and Cross-Sections 3.5 Perturbation Theory 3.6 Implications of Unitarity 3.7 Partial-Wave Expansions 3.8 Resonances Problems References4 THE CLUSTER DECOMPOSITON PRINCIPLE 4.1 Bosons and Fermions 4.2 Creation and Annihilation Operators 4.3 Cluster Decomposition and Connected Amplitudes 4.4 Structure of the Interaction5 QUANTUM FIELDS AND ANTIPARTICLES 5.1 Free Fields 5.2 Causal Scalar Fields 5.3 Causal Vector Fields 5.4 The Dirac Formalism 5.5 Causal Dirac Fields 5.6 General Irreducible Representations of the Homogeneous Lorentz Group 5.7 General Causal Fields……6 THE FEYNMAN RULES7 THE CANONICAL FORMALISM8 ELECTRODYNAMICS9 PATH-INTEGRAL METHODS10 NON-PERTURBATIVE METHODS11 ONE-LOOP RADIATIVE CORRECTIONS IN QUANTUM ELECTRODYNAMICS12 GENERAL RENORMALIZATION THEORY13 INFRARED EFFECTS14 BOUND STATES IN EXTERNAL FIELDSAUTHOR INDEXSUBJECT INDEXOUTLINE OF VOLUMEⅡ