Customer Reviews

Feynman's Thesis: A New Approach to Quantum Theory

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I did a course on quantum theory in the 1970s with John Ward who was recommended for the Nobel Prize in 1965 (Feynman, Schwinger and Tomogana shared it). Those close to the action will know of Ward's Identity. John (died in 2002 from memory) used Feynman's lectures as his course notes.

I must confess a soft spot for Feynman. I would have loved to have been in his lectures (buy his audio tapes and you will get the feel for his delivery). He was truly a great physics communicator and often understated his mathematical abilities (after all he had won the Putnam Prize at some stage so he was no mathematical slouch).

His development of QED is simple to understand and that says it all about his genius. He took the view that if he couldn't give a simple explanation then he really didn't understand the topic. The current crop of tool polishers should heed this.

Anyone who is really serious about physics (and maths) should read the original papers and this is a classic example. I suggest that you fill in the gaps in the derivations. If you can't do that then you haven't really understood it.

It is fascinating to compare Feynman's approach with Schwinger's more abstract approach. I prefer Feynman's but Schwinger does a hugely impressive job in stripping QED down to its logical (almost truth functional) essentials.

Buy this book and see how a first class mind works.

Peter Haggstrom
BONDI BEACH AUSTRALIA

In this thesis we witness a drama unfolding. The young Feynman(later to be the shining light of J.Robert Oppenheimer's theoretical physcis division of The Legendary Manhatten Project in Los Alamos, New Mexico ) is "on to
something". He has read a paper on the "New" Quantum Mechanics written by
P.A.M. Dirac which outlines a possibly new and better way to formulate the theory. One much more radically different from what the original architects (most of them German) of the theory had had in mind. But one which he intuitively ( at this point ) knows will allow him to calculate
certain results that the original formulations seem unable to manage.
That is, up until that point, 1942 no one has been able to successfully calculate the basic photon-electron interaction without getting infinity
for an answer. Which of course is no answer at all. And that's an obvious
embarrassment for the "guys" with big egos who started it all but now can't do the calculations.( if you don't believe me check out the book by Leopold Infeld: "Why I Left Canada". That will give you a real insight to some of the pettiness and viciousness among so-called "high brow" intellectuals.)

He's right at the forefront of knowledge at this point and he knows it.
Nobody is contemplating or attempting to do what he's about to do. Neither
will they be able to understand it. This of course supplies the excitement
of the quest. He is on an adventure and he is doing it himself. And what comes out of the mathematical analysis done in this thesis will eventually lead to a brand new way of calculating Qunatum Mechanical events. One which will conveniently obviate the traps and pitfalls inherent in all of these failed attempts. And that new mathematical construction will be called a " Path Integral". Which in turn
will evolve into the now-famous "Feynman Diagrams" (a better and more efficient way to calculate these subatomic processes.) And which will eventually provide
a beautiful way to try to envision the Quantum phenomenon known as "entanglement".

The stakes are high at this point. The tension and competition are telling to say the least. Who will be first to get there? If Feynman were
to fail in this attempt it would be a great loss of face. But very dramatically just a few years after this thesis he succeeds in such a novel and clever way that it draws both praise and condemnation from the various "camps" of theoretical physics. Ultimately it will result in his sharing in the 1965
Nobel Prize for physics.

The young Feynman has not only won the day but has advanced the prestige of "American Physics" significantly further right on the heels of America's successful creation of the world's first Nuclear device. This would not be Feynman's only triumph. There would be in fact many, many more.

It is significant to note that one of the first professors ever to include Feynman's Path Integral formulation of Quantum Electrodynamics in his lectures
in the 1950's was none other than Wolfgang Pauli. ( Nobel Prize in physics 1945 unshared ) To those who are privy to the enigmatic workings and personalities of the community of theoretical physics at that time (and even now )acceptance
by Pauli would to some have exceeded a Nobel Prize. Now that truly would have been an exciting achievement.

Southern Jameson West
p.s. also, in the book Feynman offers a fair albeit non-rigorous explanation of the mathematical concept of "Functionals".
See my review on Morse and Feshbach

The section on quantum superposition and the essential difference between classical and quantum approaches, found in the article "Space-Time Approach to Non-Relativistic Quantum Mechanics", is mind-blowing stuff. This is a great book.

Having access to the early ideas that lead R. P. Feynman to the eventual development of his path integral theory of Quantum Mechanics is invaluable.

The book is not bad but also not in the same class as his lectures. Good for undergraduates as a quick read.