Introduction 7
I. Form Factors and their Spectral Representation 8
1. Form Factors 8
2. Asymptotic Properties and Types of Representations 8
3. Dispersion Relations 9
4. Form Factors and Scattering Amplitudes 10
II. The Scattering Amplitude 11
1. Formulation of the Problem in Relativistic Quantum Theory 11
2. The Scattering Matrix and the Invariant Amplitude 12
3. Kinematic Invariants 13
4. Symmetry of the Scattering Matrix 14
5. The Principle of Universality 14
6. Generalization to Particles with Spin and Isospin 16
III. Unitarity and Analyticity 18
1. The Unitarity Relation 18
2. The Imaginary Part of the Amplitude. The Optical Theorem 18
3. The Principle of Analyticity 19
4. Poles of the Amplitude 20
5. Two-particle Intermediate States 21
6. Triangle Diagrams 22
7. Square Diagrams 25
8. The Mandelstam Representation 26
IV. Electromagnetic Structure of Particles 27
1. Scheme of Construction of Perturbation Theory 27
2. Vacuum Polarization 29
3. Structure of the Electron 30
4. Pion Form Factor 31
V. Some Applications of the Theory of Dispersion Relations 32
1. Dispersion Relations for Meson-Nucleon Scattering 32
2. Dispersion Relations for Forward Scattering. Coupling Constants of Strong Interactions 33
3. Pomeranchuk's Theorem 34
4. Peripheral Collisions 35
Literature References 36