QED: The Strange Theory of Light and Matter is a collection of four lectures where he seeks to explain, to a non-specialist audience, the theory of Quantum Electrodynamics (for which he'd been given the Nobel Prize). The circumstances of these lectures are worth noting, as Feynman had a wide circle of friends, one couple (of means) had funded a series of lectures and invited Feynman to launch the series with the four in this book (which came five years before his death in 1988).
The four lectures here are titled "Introduction” (which faked me out, as I was expecting a few pages of intro, but this runs a quarter of the book!), “Photons: Particles of Light”, “Electrons and Their Interactions”, and “Loose Ends”, and in them Feynman takes the reader through an increasingly challenging information curve (I admit, he did manage to “lose me” at a couple of points towards the end). Feynman warns the listener/reader early on, saying “What I am going to tell you about is what we teach our physics students in the third or fourth year of graduate school – and you think I'm going to explain it to you so you can understand it?”. Of course, despite my passing familiarity with the topic, I had issues with parts of it (albeit not the concept of the “absurdity of Nature”), but I also had some of those much-treasured “AHA!” moments where he clarifies something that I knew of, but did not fully “get”.
Prime among these revelations was the “inner workings” of the basic Feynman Diagrams. I had encountered these in various contexts over the years, and understood that they represented visualizations of how particles can exchange, emit, and absorb other particles as they move through space/time (even, arguably, backwards in time). I had never known, however, the ways these were specifically drawn out. One of the first things that Feynman deals with here is how those lines are developed, with a “clock hand” that spins at different rates depending on the particle and its vibration (i.e., pure blue light's dial “spins” faster than pure red light). Each of these produces a reading which involves length and direction, and all possible states for an event are calculated, and a resulting arrow created. Needless to say, this can become very complicated!
Of course, one of the most endearing aspects to Dr. Feynman was his wry humor … which helps to sugar-coat many difficult concepts here. I thought I'd share at least one, and had found this particularly amusing as I was reading through the book:
… doesn't it sound so simple when put that way?There was also the problem of what holds the neutrons and protons together inside the nucleus. It was realized right away that it could not be the exchange of photons, because the forces holding the nucleus together were much stronger – the energy required to break up a nucleus is much greater that that required to knock an electron away from an atom in the same proportion that an atomic bomb is more destructive than dynamite: exploding dynamite is a rearrangement of the electron patterns, while an exploding atomic bomb is a rearrangement of the proton-neutron patterns.
Anyway, this does appear to be in print (and, judging from the numbers of copies held on LibraryThing, I'm guessing that the “Princeton Science Library” edition is used as a textbook), so, should you have a burning desire to come to a fresh appreciation of the inner workings of nature (at least to the extent that Quantum Electrodynamics describes them), it should be easy enough to find a copy. Amazon has it at a very reasonable 32% discount from (a very reasonable) cover price, which is only slightly bettered by the new/used guys (after shipping, of course). Again, I realize that reading physics for relaxation is not most folks' first choice, so I won't insist that your intellectual development is not complete without this, but do consider picking up some Feynman ("Surely You're Joking..." is probably a much better introduction to the man and his thought anyway) to familiarize yourself with one of the most amazing humans to have graced the planet!