I am very happy to accept the translators' invitation to write a few lines of introduction to this book. Of course, there is little need to explain the author. Pauli's first famous work, his article on the theory of relativity in the Encyc!opiidie der Mathematischen Wissenschaften was written at the age of twenty. He afterwards took part in the development of atomic physics from the still essentially classical picture of Bohr's early work to the true quantum mechanics. Thereaftt'f, some of his work concerned the treatment of problems in the framework of the new theory, especially his paper on the hydrogen atom following the matrix method without recourse to Schrodinger's analytic form of the theory. His greatest achievement, the exclusion principle, generally known today under his own name as the Pauli principle, that governs the quantum theory of all problems including more than one electron, preceded the basic work of Heisenberg and Schrodinger, and brought him the Nobel prize. It includes the mathematical treatment of the spin by means of the now so well- known Pauli matrices.
In 1929, in a paper with Heisenberg, he laid the foundation of quantum electrodynamics and, in doing so, to the whole theory of quantized wave fields which was to become the via regia of access to elementary particle physics, since here for the first time processes of generation and annihilation of particles could be described for the case of the photons.
I The Uncertainty Principle and Complementarity.- 1. The Uncertainty Principle and Complementarity.- 2. The Measurement of Position and Momentum.- II Schrodinger Equation and Operator Calculus.- 3. The Wave Function of Free Particles.- 4. The Wave Function of a Particle Acted on by Forces.- 5. Many-Particle Interactions - Operator Calculus.- III Stationary States and the Eigenvalue Problem.- 6. Stationary States as Eigenvalue Problem.- Chpater IV Matrix Mechanics.- 7. General Transformations of Operators and Matrices.- 8. The General Form of the Laws of Motion.- V Theory of Measurements.- 9. Determination of the Stationary States of a System through Measurement: General Discussion of the Concept of Measurement.- VI Approximation Methods.- 10. The General Formalism of Perturbation Theory.- (a) Stationary State Perturbation Theory.- (b) Time-dependent Perturbation Theory.- 11. Adiabatic and Sudden Perturbations.- (a) Adiabatic and Sudden Perturbations of a System.- (b) The Most General Statement on Probability in Quantum Mechanics.- 12. The W K B Approximation.- (a) Limiting Transition to Classical Mechanics.- (b) Relation to the Old Quantum Theory.- VII Identical Particles, Spin and Exclusion Principle.- 13. Hamiltonian Functions with Transformation Groups. Angular Momentum and Spin.- (a) Group Theoretical Considerations.- (b) Wave Functions for Particles with Spin.- 14. The Behaviour of Eigenfunctions of Many Identical Particles Under Permutation. The Exclusion Principle.- (a) Permutations and the Symmetry of Eigenfunctions.- (b) The Exclusion Principle.- VIII Semiclassical Theory of Radiation.- 15. Treatment of the Radiation Processes Based on the Correspondence Principle.- 16. Application of the Semiclassical Theory to the Coherence Properties of Radiation.- IX The Relativistic One-Particle Problem.- 17. Introduction.- 18. Dirac's Wave Equation for the Electron. Free Particle Case.- 19. Relativistic Invariance.- 20. The Behaviour of Wave-Packets in the Free Particle Case.- 21. The Wave Equation when Forces are Present.- 22. Approximations of the Dirac Theory: The Non-relativistic Quantum Mechanics of Spin as First Approximation.- 23. Approximations of the Dirac Theory: Limiting Transition to the Classical, Relativistic Particle Mechanics.- 24. Transitions to States of Negative Energy. Limitations of the Dirac Theory.- X Quantum Electrodynamics.- 25. Quantisation of the Free Radiation Field.- (a) Classical Theory.- (b) Quantisation.- (c) Limits of Accuracy on the Measurement of Field Strengths.- (d) Transition to the Configuration Space of Photons.- 26. Interaction Between Radiation and Matter.- 27. Self-Energy of the Electron. Limits of the Present Theory.