Geometrization in the Yang-Mills, extended supergravity, and Klein-Kaluza versions

Abstract

We relate personal encounters of three kinds with geometrical approaches in the development of a relativistic quantum field theory of the fundamental interactions—including interactions with Nathan Rosen. We characterize the geometrical structures involved and discuss the more recent attempts to develop a unified theory based on a Klein-Kaluza contraction of the eightfold extended supergravity.