The Cult of Theory

Over at Cosmic Variance, Julianne (not JoAnne, as I originally typed) has a very nice post about the cult of genius in physics, and its relationship to research on the problems caused by excessive praise. Doug Natelson also has some comments. There’s some fascinating stuff in the articles about praise, with some likely relevance to once and future education arguments, but I need to think about it more before I comment.

My reason for posting, though, is found in the comments. Specifically, comment #10, by “mclaren”, which reads in part:

Sure, I’ve got a degree in physics, but basically I’m too stupid to do anything useful. Linear homoegeon partial differential equations I can handle, conformal mapping and so forth, but that’s kiddy math. It’s trivial. That’s not real math. That undergrad stuff. The vast majority of the human race, including me, can’t do _real_ math. Case in point: I took a course on algebraic topology in college…

If you want to find a pernicious meme that’s a blight on the face of physics, it’s not the over-idolization of “genius,” exemplified by Einstein and Feynman, it’s this crap. Too many people approach physics as if there’s some sort of Great Chain of Being, with the most abstract theoretical particle physics at the very top and low-energy experimentalists down at the bottom, just above biologists and rude beasts incapable of speech.

This drives me right up the wall.

There’s no inherent moral worth to working on more “fundamental” and mathematical physics. A lack of familiarity with algebraic topology is not a defect in character, or a sign of gross stupidity. Low-energy physics is different than high-energy theory, but not inferior to it.

Lots of people have responded to mclaren’s comment, mostly with “Don’t feel bad, lots of other people are too dumb to be high-energy theorists, too,” and while I’m sure that’s some comfort, it misses the real point. It’s still buying into the myth that high-energy particle theory is the highest possible calling. This is as poisonous for the profession as the idea that, as Doug puts is, “if you get a physics PhD but don’t end up a full professor at Harvard, you’re a plodder.”

In fact, I have a much higher regard for phenomenologists than “pure” theorists, and an even higher regard for experimentalists. They don’t get to set inconvenient constants equal to one, or approximate away all the hard problems, but instead have to deal with the world as it really is. In my opinion, there’s a lot more ingenuity involved in figuring out clever ways to measure the dependence of gravity at very short length scales, or electric dipole moments at the 10-30 level than there is in figuring out yet another of the 10500 possible ways of wrapping hypothetical extra dimensions around hypothetical warped manifolds in whatever the toy model of the moment is.

And yet there’s this persistent myth that the highest form of achievement in physics is whatever is farthest removed from reality. Students learn to idolize people who noodle around with abstract math, while the people who do the genuinely difficult work of connecting abstract math with experimentally measurable reality are dismissed as mere tinkerers who couldn’t cut it in the world of high-energy theory.

The worst part of this is that it’s not even particularly consistent with the “cult of genius.” The thing about Feynman that was really remarkable was not his facility with abstract math, but rather his physical intuition. The people who are justly hailed as among the very best physicists of the modern era– Feynman and Einstein, as well as people like Bohr and Fermi– had a gift for making abstract physics concrete, not for doing algebraic topology.

Einstein’s “miraculous year” of 1905 wasn’t founded on great mathematical leaps– Lorentz and FitzGerald had come up with time dilation and length contraction earlier. Einstein’s great accomplishment was more in making relativity obvious and acceptable, in coming up with a clear and concrete physical picture that showed why the bizarre consequences of relativity are correct, and moreover have to be correct. Feynman’s theory of QED doesn’t have the mathematical elegance or rigour of Schwinger’s theory, but Feynman is better known because he provided an intuitive way of thinking about the theory that makes it useful. And it’s worth noting that the pinnacle of Feynman mythology is an experiment, not a theoretical development– his O-ring demonstration at the Challenger hearings.

It’s absolutely crazy for mclaren to be beating himself up for not knowing algebraic topology, and yet, that’s what the cult of theory does– it rates the most abstract and incomprehensible material above the concrete and practical, in complete defiance of reality. It’s absolutely maddening.

(Even if you restrict the discussion to the theory side, I don’t buy it. People like John Bell, or Peter Shor, or Woijciech Zurek are (or were, in the case of Bell) scary smart, and don’t need algebraic topology to do fundamental theoretical physics. And I’d match their accomplishments against anything Ed Witten ever dreamed up.)