The chapter "Elementary Theory of Angular Momentum" by M. E. Rose, Chief Physicist at Oak Ridge National Laboratory, provides an introduction to the fundamental concepts and theories related to angular momentum. The text likely covers key principles, mathematical formulations, and applications in physics, focusing on the behavior and properties of angular momentum in various physical systems.The chapter "Elementary Theory of Angular Momentum" by M. E. Rose, Chief Physicist at Oak Ridge National Laboratory, provides an introduction to the fundamental concepts and theories related to angular momentum. The text likely covers key principles, mathematical formulations, and applications in physics, focusing on the behavior and properties of angular momentum in various physical systems.