Tuesday, July 14, 2009

Review: Six Not-So-Easy Pieces, by Richard P. Feynman

I have, over the years, spent a lot of time on the internet, and the sort of argument styles you find online have started to grate after awhile. Not to say it's surprising, you'll meet ten people a day whose self estimation exceeds their capability, but the digital fields have propagated a certain strain, the self-styled Vulcans or the Slans finally given their opportunity to shine in a purely intellectual medium, and okay, a few of them do shine, even in political arenas, but I'm increasingly convinced that quality thinking is a rare flower even among the Comic Book Guy set, that intelligence and a penchant for declarative sentences may not be sufficient to overcome the various self-deceptions, inappropriate generalizations, faulty logic, bad weighting of counterargument, inability to distinguish hindsight from foresight, and all the rest of the bestiary of cognitive curlicues that obstruct most minds from grasping the nature of things in a broad but generally accurate and consistent sense.* Now and then, a great or even exceptional thinker will emerge, and rarer still will that thinker be able to communicate with accuracy, humor, and humility. Feynman was a gem.

Of course, one of the side effects of reading Feynman is that once that high of uncut understanding wears off, your own brain feels a little muddier afterwards. I think that the audience that evolved to love this guy is primarily composed of scientists looking for deeper meaning into what they already know. (I suppose I could put myself into this group, although without doubt, relativity isn't something I already know in a meaningful way.) These lectures were great at communicating insight, but they're actually lean on facts. I not at all certain that I'd have wanted to learn freshman physics from this guy. I wouldn't have been left with the tools to do the problem sets.

What I didn't realize when I picked this up, is that they're six connected pieces. The progression here, examining the laws of physics through geometrical transformations, holds together cleverly and proceeds naturally to relativity. I further appreciated the discussion of the contemporary setting of Einstein's theories, what he was specifically trying to address with them, and that the Lorentz transformations (which in special relativity, Einstein explained the validity of) had already been thrown out there as fudge factors to explain the discrepancies between predictions of Maxwell's equations (where it falls out as a constant in the simplest EM wave equation) and what's expected by conventional expectations of relative motion, as well as the confusing experiments that were going on when the great man was busy theorizing. The context makes relativity seem a lot less weird, frankly.

I recall reading that one of Einstein's proudest achievments was his index notation for vectors. Basically, he simplified the math symbols so that you don't have to write big brackets, or unit vectors, or summations. It's pretty intuitive and handy, occasionally adopted formally by fluid mechanics nerds (which Einstein dabbled in), and frequently informally by any hack engineer who's tried his** hand at primitive excuses for number crunching. If you ask a mechanics guy and a computer guy, both inclined to use index notation, what's the meaning of a "vector," you'll probably get two different answers, and thinking this way, I'd have rather seen Feynman move down from the general, in which a vector is a column of numbers of arbitrary length, which is merely limited to three when it needs to describe Euclidian space, or, presumably, four when describing Minkowski space. (How dare he present this subject forty years ago!) It's not immediately clear that the innovation couldn't have been constrained to new algebraic operations specified to describe relativistic effects in 4-D space, rather than specifying a new sort of space in which the fourth dimension has separate properties. I will say that the geometrical analyses that Feynman described struck me as very clever. ("Clever." I mean it's Einstein here--this is like a mosquito calling a jetliner sort of large.) I suppose I'd have to do problem sets to get the real scoop on it all (and I've no interest in that).

In one of the lectures, Feynman had a great bit about using measurement as a tool for explaining the universe, and took an entertaining poke at fly-by know-it-alls who'd pretend it's intuitive (he's favoring empiricism over pure rationalism I guess, but he didn't frame it that way). That discussion of how the geometry of space time could be deduced from within the system was the most animated, and, I think the most successful application of his grand insight, and it occurs to me I've seen a dozen explanations along the same lines (usually with graphics of marbles making dimples in a computer-generated 2-D grid) that, unlike Feynman's analogies, were not terribly intelligible at all. I've caught the bug's-eye thing before too and the jumpy speaking style too (I don't usually "hear" when I read, but I could feel Feynman speaking in this one), and it occured to me that many of my professors were among the generation of (inevitably lesser) Feynman copycats.


* Alternate theory: I'm projecting.
** For a possible theory about my use of gendered pronouns, see note 1.

12 comments:

LentenStuffe said...
This comment has been removed by the author.
Schmutzie said...

John's right. I enjoyed this very much. One of the greatest things about his was his ability to teach. I've often thought that his students must have had that same muddy headed feeling after a Feynman lecture, and not minding the sensation one bit.

Leighton spoke of how Cal Tech students used to copy RPF's style, including doing impersonations of the way he "just threw equations up on the board."

Apparently, blank blackboards were filled with enormous amounts of info with a great flourish, and then when he'd finish he'd turn and face the lecture hall with arms extended and palms turned upward as if to say.."See? It's just that simple."

The Feynman Diagram

He was a true original. Thanks for this K.

Keifus said...

I enjoyed it (and should no doubt listen to the lectures, but who has time?). Thanks for the recommendation.

Keifus said...

John? Thanks for the recommendation. Was thinking a lot of your earlier comments as I read, trying to imagine how good a learning tool this really was.

I didn't do a lot of formal physics classes outside of the core stuff for undergrad. Those guys were a bit too old to have R.P.F. inspire their teaching much. [Mr. Rogers was a more likely candidate as model teacher (and all were quite good, actually)]. Younger enthusiastic professors were the chemistry and materials ones, and one of them was particularly high strung, big New York accent and all, and a Feynman influence is possible. He flustered himself pretty easily though, to the amusement of us all.

LentenStuffe said...

K,

I'm dipping into "What Do You Care What Other People Think?" Great narrative skills he had.

I was thinking of M's top-post with regard to the chapter, "Mr Feynman goes to Washington: Investigating the Space Shuttle Disaster", especially the epilogue, "The Value of Science", where he writes, quoting Buddha, 'To every man is given the key to the gates of heaven; the same key opens the gates of hell.'

Cheers.

Schmutzie said...

A fabulous epilogue, and I love the fact that he insisted on adding his own appendix to the report. He was right too. The designers of the shuttle were pie-in-the-sky with regards to likelihood of crew loss.

The exchange between RF and Gen Kutina (?) are fantastic.

Schmutzie said...

I found it.

Feynman's Appendix F

Aaron said...

You're a more patient man than I, K. I found that the argument styles practiced by many on the Internet grate immediately. But I'm old and cranky so maybe I don't count.

I have always had a love-hate relationship with physics. As much as I enjoy learning about the workings of the Universe, I can't handle the mathematics, and so it always leaves me feeling dim and undereducated.

Keifus said...

I've tried to keep an open mind over the years, and in some areas I started out pretty naive. I'm older and crankier now too.

It's good to be able to follow along the math (was advised once to read it as a conversation), but it's another matter to get in and muck around in its depths. I consider that an exercise of last resort. It happens on rare occasions. (Call it my nature, but my career also encourages being an inch deep in everything.)

Ben There said...

Keifus, that is one impressive first sentence you've got going on there. I've only read one of
Feynman's works, "QED", and it blew me away on multiple levels.

Keifus said...

I plan on getting to QED shortly after I read Ulysses.

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