The Feynman Lectures on Physics
Jun. 23rd, 2005 12:55 am![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
mmcirvinA post about pedagogical style by Chad Orzel, which name-checks Richard Feynman, leads to the perennial discussion of whether the Feynman Lectures on Physics are really any good. Feynman himself thought the associated class was something of a failure, but apparently others disagreed.
I'm not sure that the lectures would be good material for an introductory course, but I am sure that they make excellent remedial crib sheets for graduate students. My parents bought me a copy of the lectures many years ago when I was a young teenager, and I remember finding them a little beyond me; my parents were always just a little chagrined that I never cracked these expensive books after that.
They actually stayed on the shelf unopened all through college, but then I took them with me to graduate school. When I discovered in my first year that I didn't know undergrad physics as well as I thought I did, let alone well enough to be comfortable with first-year graduate classes, the Feynman Lectures came off the shelf and saved me. It was all in there somewhere, explained in a manner that was just enough quirkily different from the standard textbook treatments that I'd get a much better understanding of the common thing that the different explanations were aiming at. I kept coming back to them over and over through my grad-school career, always finding some new and helpful insight.
The first two volumes, on Newtonian mechanics, electromagnetism and thermodynamics, are great stuff, but it's the third volume's treatment of quantum mechanics that really immortalized the series. It is an utterly radical exposition whose sequence of topics bears no relation to the usual classroom development starting with the one-dimensional Schrödinger wave equation, and it was a major influence on subsequent texts such as Sakurai's first-year-graduate-level QM textbook.
Feynman starts with spin systems, which are mathematically very simple (matrix algebra with small matrices) but are also starkly alien in their behavior, hitting you with quantum weirdness in full force right out of the starting gate. The advantage of this is that you get the concepts raw without being distracted by mathematical methods for solving differential equations; the disadvantage is that there's no reassuring limiting connection to classical mechanics or quasi-historicist application to the atom until you've played in this vertigo-inducing subatomic world for quite a while. All I can say is that it's a great second way to learn quantum mechanics.
I'm not sure that the lectures would be good material for an introductory course, but I am sure that they make excellent remedial crib sheets for graduate students. My parents bought me a copy of the lectures many years ago when I was a young teenager, and I remember finding them a little beyond me; my parents were always just a little chagrined that I never cracked these expensive books after that.
They actually stayed on the shelf unopened all through college, but then I took them with me to graduate school. When I discovered in my first year that I didn't know undergrad physics as well as I thought I did, let alone well enough to be comfortable with first-year graduate classes, the Feynman Lectures came off the shelf and saved me. It was all in there somewhere, explained in a manner that was just enough quirkily different from the standard textbook treatments that I'd get a much better understanding of the common thing that the different explanations were aiming at. I kept coming back to them over and over through my grad-school career, always finding some new and helpful insight.
The first two volumes, on Newtonian mechanics, electromagnetism and thermodynamics, are great stuff, but it's the third volume's treatment of quantum mechanics that really immortalized the series. It is an utterly radical exposition whose sequence of topics bears no relation to the usual classroom development starting with the one-dimensional Schrödinger wave equation, and it was a major influence on subsequent texts such as Sakurai's first-year-graduate-level QM textbook.
Feynman starts with spin systems, which are mathematically very simple (matrix algebra with small matrices) but are also starkly alien in their behavior, hitting you with quantum weirdness in full force right out of the starting gate. The advantage of this is that you get the concepts raw without being distracted by mathematical methods for solving differential equations; the disadvantage is that there's no reassuring limiting connection to classical mechanics or quasi-historicist application to the atom until you've played in this vertigo-inducing subatomic world for quite a while. All I can say is that it's a great second way to learn quantum mechanics.
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no subject
Date: 2005-06-23 03:20 am (UTC)But I worked through it again about twice more that summer and then aced the intro QM course at Caltech, where most of the other students seemed also at sea even with a fine lecturer and a different textbook. It looked like there was just no good way to teach this so that sophomores can understand it, the first time through. After the final people getting their marked-up exam papers back were going like, "But how can that be?"
Maybe now with newer ideas from quantum computing, etc., it'd be easier to confront the weirdness in a first course. I still haven't really learned those ideas myself.
no subject
Date: 2005-06-23 03:33 am (UTC)I think I was less impressed with the material on electromagnetism and relativity than the rest of it; Feynman's treatment of special relativity is fairly conservative compared to the other stuff and not the way I'd teach it (he emphasizes "relativistic mass", if I recall correctly; it's slightly ironic, since the elegance of his own covariant formulation of QED is a large part of the reason why particle theorists hate that concept so much). But the volume-2 material on thermodynamics is pretty good (it's in there, right?)
There may be an inverse relation between how impressive parts of the series are to people re-educating themselves, and how useful they are to introductory students.
no subject
Date: 2005-06-23 04:08 am (UTC)I don't know how it works for other people, but as a beginning student I absolutely loved the first and third volumes, after beating my head against the latter for a while. The second I never mastered to the same degree, since it seemed harder and quantum mechanics interested me more. (Maybe I didn't know the volume-1 prerequisites as well as I thought.) Topics like the self-energy of the electron were broadening but hard to connect to any new ability to solve problems at my level. I'm glad they were there -- that's the sort of thing I miss in most textbooks -- but it's easy to see why some people say they're not for beginners.
no subject
Date: 2005-06-23 05:31 am (UTC)(rummage, rummage) Here-- the title is "Capturing the Wisdom of Feynman." It's available online here only if you are a subscriber. I photocopied the article, but haven't yet read it.
no subject
Date: 2005-06-23 12:42 pm (UTC)Still, incomprehensible to the unexposed.
I think the process of learning is really just repetition and familiarity, and having someone there to correct your inevitable mistakes and blunders.
Hence those three red books will never replace a 4 year college degree.