The Principle of Least Action - History and Physics (Relié)

The principle of least action originates in the idea that Nature has a purpose and thus should follow a minimum or critical path. This basic principle, with its variants and generalizations, applies to optics, mechanics, electromagnetism, relativity and quantum mechanics, and provides a guide to understanding the beauty of physics. This text provides an accessible introduction to the action principle across these various fields of physics and examines its history and fundamental role in science.
It includes explanations from historical sources, discussions of classic papers, and original worked examples. Different sections require different levels of mathematical sophistication. However, the main story line is accessible not only to researchers and students in physics and the history of physics, but also to those with a more modest mathematical background.