An Invitation to Quantum Field Theory

This book provides an introduction to Quantum Field Theory (QFT) at an elementary level '¬ ; with only special relativity, electromagnetism and quantum mechanics as prerequisites. For this fresh approach to teaching QFT, based on many lectures and courses given by the authors, a representative sample of topics containing some of the more innovative, challenging or subtle concepts have been selected. They are presented with a minimum of technical details, the discussion of the main ideas being more important than the presentation of the typically very technical mathematical details necessary to obtain the final results. Special attention is given to the realization of symmetries in particle physics: global and local symmetries, explicit, spontaneously broken, anomalous continuous symmetries, as well as discrete symmetries. Beyond providing an overview of the standard model of the strong, weak and electromagnetic interactions and the current understanding of the origin of mass, the general features of renormalization theory as well as a cursory description of effective field theories and the problem of naturalness in physics are given. Among the more advanced topics the reader will find an outline of the first principles derivation of the CPT theorem and the spin-statistics connection. As indicated by the title, the main aim of this text is to motivate the reader to study QFT, by providing a self-contained and approachable introduction to the most exciting and challenging aspects of this successful theoretical framework.