Rudolf Haag's legacy of Local Quantum Physics and reminiscences about a cherished teacher and friend

Abstract

After some personal recollectioms about Rudolf Haag and his thoughts which led him to "Local Quantum Physics", the present work recalls his ideas about scattering theory, the relation between local observables and localized fields and his contributions to the physical aspects of modular operator theory which paved the way for an intrisic understanding of quantum causal localization in which fields "coordinatize" the local algebras. The paper ends with the presentation of string-local fields whose construction and use in a new renormalization theory for higher spin fields is part of an ongoing reformulation of gauge theory in the conceptual setting of Haag's LQP.