Field Theory Concepts

Field Theory Concepts

"Field Theory Concepts" is a new approach to the teaching and understanding of field theory. Exploiting formal analo- gies of electric, magnetic, and conduction fields and introducing generic concepts results in a transparently structured electomagnetic field theory. Highly illustrative terms alloweasyaccess to the concepts of curl and div which generally are conceptually demanding. Emphasis is placed on the static, quasistatic and dynamic nature of fields. Eventually, numerical field calculation algorithms, e.g. Finite Element method and Monte Carlo method, are presented in a concise yet illustrative manner.

Field Theory Concepts

The Conceptual Framework of Quantum Field Theory

The book attempts to provide an introduction to quantum field theory emphasizing conceptual issues frequently neglected in more "utilitarian" treatments of the subject. The book is divided into four parts, entitled respectively "Origins", "Dynamics", "Symmetries", and "Scales". The emphasis is conceptual - the aim is to build the theory up systematically from some clearly stated foundational concepts - and therefore to a large extent anti-historical, but two historical Chapters ("Origins") are included to situate quantum field theory in the larger context of modern physical theories. The three remaining sections of the book follow a step by step reconstruction of this framework beginning with just a few basic assumptions: relativistic invariance, the basic principles of quantum mechanics, and the prohibition of physical action at a distance embodied in the clustering principle. The "Dynamics" section of the book lays out the basic structure of quantum field theory arising from the sequential insertion of quantum-mechanical, relativistic and locality constraints. The central role of symmetries in relativistic quantum field theories is explored in the third section of the book, while in the final section, entitled "Scales", we explore in detail the feature of quantum field theories most critical for their enormous phenomenological success - the scale separation property embodied by the renormalization group properties of a theory defined by an effective local Lagrangian.