Beat of a Different Drum: The Life and Science of Richard Feynman - Jagdish Mehra - Hardcover Book

This is an excellent book about the life and the many achievements of Richard P. Feynman. It was written by a former colleague of Feynman's who had the advantages of having an extensive background in theoretical physics and who also knew Feynman personally.
The author begins by describing Feynman's birth on May 11, 1918 in Queens, NY, and about his early intensive scientific development. Feynman was seen as a whiz kid in mathematics in elementary school, and he began fixing radios for money at an early age. He taught himself algebra and calculus in high school with the help of a few good books. It was at this time that he became an expert an integration and also learned about the principle of least action in physics, two things which would become fundamental to his later work.
Feynman's undergraduate days at MIT are recounted (1935-1939), including the books which were most influential on him, mainly Dirac's book on the principles of quantum mechanics, Arthur Eddington's mathematical theory of relativity, and Heitler's book on the quantum theory of radiation. Although Feynman was quite talented with his hands and extremely good at experimental physics, he decided at that point that the study of theoretical physics was the path he wished to follow.
The book describes how Feynman went on to Princeton for his graduate studies and how he became an assistant to Professor John Wheeler. They formed a deep friendship and collaborated on several interesting ideas and papers.
The book then describes how Feynman was able to clarify and formulate the principle of least action in quantum mechanics. In classical systems, the principle was first laid out by Maupertis in 1744, and also by Euler in 1744. Lagrange also did some work in this area, but it was actually the Irish physicist and mathematician William Rowan Hamilton who provided us with the modern classical formulation of the principle (a good book on Hamilton which I recommend is "William Rowan Hamilton: Portrait of a Prodigy" by Sean O'Donnell).
Feynman hadn't yet completed his doctorate when in April of 1942, he became a member of a theoretical physics group working on the Manhattan Project at Los Alamos. He worked with several other great physicists there, including Hans Bethe, Victor Weisskopf, Robert Wilson, and Robert Oppenheimer. One of the things Feynman did for entertainment there was to become an expert at opening safes and picking locks! He also began to enjoy drumming with his hands.
The book relates how after the Manhattan Project, he obtained his doctorate, and since he wished to continue working with Hans Bethe, he accepted a position as a professor at Cornell University in Ithaca, NY.
This book is particularly good at describing the thought processes which led up to his revolutionary and influential papers of 1948 and 1949 on the space time approach to quantum theory, where Feynman developed his ideas about path integrals and the superposition of amplitude techniques. Feynman was able to come up with the analogue to Christian Huygens' principle, applied to matter waves rather than electromagnetic waves. The book describes in a clear fashion how Feynman arrived at his results and how he was very good about checking them against other known results (such as Julian Schwinger's) as often as possible to ensure accuracy. When Feynman came up with his theory of Quantum Electrodynamics (QED) for which he, Schwinger, and Tomonaga won the 1965 Nobel Prize, it was Freeman Dyson (BA, Cambridge) who was able to prove that Feynman and Schwinger's formulations were actually equivalent. Interestingly, Dyson once described Feynman as "half genius, half buffoon"!
The book describes how Feynman worked in other scientific areas as well, and how he made contributions to the theory of superfluidity, polarons, quantum gravity, particle physics, and also how he uncovered the cause of the space shuttle Challenger disaster. The book also contains some excellent photographs, including some of Feynman and the author, Feynman with Schwinger, one with Paul Dirac, and also an interesting image of Feynman's face superimposed on a drawing of the great Isaac Newton. There is also information on Feynman's legendary teaching methods which he developed at Caltech and his pastimes.
Overall, this is a masterly and detailed work on how Richard Feynman developed his brilliant ideas and why he shall be remembered as one of the finest and most original minds of all time.