Classical solutions in quantum field theory: solitons and instantons in high energy physics

This book examines the nature of the coherent excitation produced in atoms by lasers, as well as the details of the transient variation of excited-state populations with time and how these depend upon such controllable parameters as laser frequency and intensity. It emphasizes the physical and mathematical theory that underlies contemporary description of this excitation. It is concerned with temporal behaviour rather than with the characteristic energy levels of the stationary status of atoms. In Volume 2, Part IV a variety of multi-state extensions of the simple two-state atom, beginning with three- state models and continuing to finite and infinite chains of excitation are examined. Part V presents and applies the theory of angular momentum to coherent excitation. The final part examines a number of extensions of coherent excitation, concluding with the theory of random processes and applications to the fluctuations that inevitably accompany excitation and act to destroy coherence. A set of appendices summarize background material "Classical solutions play an important role in quantum field theory, high-energy physics, and cosmology. Real-time soliton solutions give rise to particles, such as magnetic monopoles, and extended structures, such as domain walls and cosmic strings, that have implications for the cosmology of the early universe. Imaginarytime Euclidean instantons are responsible for important nonperturbative effects, while Euclidean bounce solutions govern transitions between metastable states. Written for advanced graduate students and researchers in elementary particle physics, cosmology, and related fields, this book brings the reader up to the level of current research in the field"-- Machine generated contents note: 1. Introduction; 2. One-dimensional solitons; 3. Solitons in more dimensions -- vortices and strings; 4. Some topology; 5. Magnetic monopoles with U(1) charges; 6. Magnetic monopoles in larger gauge groups; 7. Cosmological implications and experimental bounds; 8. BPS solitons, supersymmetry, and duality; 9. Euclidean solutions; 10. Yang-Mills instantons; 11. Instantons, fermions, and physical consequences; 12. Vacuum decay; Appendixes; References; Index