This book provides a readable account of the foundations of QFT, in particular of the Euclidean formulation with emphasis on the interplay between physical requirements and mathematical structures. The general structures underlying the conventional local (renormalizable) formulation of gauge QFT are discussed also on the basis of simple models. The mechanism of confinement, non-trivial topology and *vacua, chiral symmetry breaking and solution of the U(1) problem are clarified through a careful analysis of the Schwinger model, which settles unclear or debated points.

Devoted to modern problems of quantum optics, this book investigates atomic radiation in free space, waveguides, cavities and periodical structures. The wavepacket quantum-mechanical picture of radiation is stressed and different states of the radiation field are described.

This volume emphasizes the primary role played by images in computer science. In the last two decades images have replaced written texts and the enormous possibilities of the image language have overcome written language in an ever-more-restricted ambit.