This book presents a functional approach to the construction, use and approximation of Greens functions and their associated ordered exponentials. After a brief historical introduction, the author discusses new solutions to problems involving particle production in crossed laser fields and non-constant electric fields. Applications to problems in potential theory and quantum field theory are covered, along with new approximations for the treatment of color fluctuations in high-energy QCD scattering. Suitable for graduate students and researchers in a wide range of fields, including quantum field theory, fluid dynamics and applied mathematics.
Inhaltsverzeichnis
Preface; 1. Introduction; 2. Elementary functional methods; 3. Schwinger-Fradkin methods; 4. Lasers and crossed lasers; 5. Special variants of the Fradkin representation; 6. Quantum chaos and vectorial interactions; 7. Infrared approximations; 8. Models of high-energy, non-Abelian scattering; 9. Unitary ordered exponentials.