04 February 2007

Gobbledygook in physics

Following on from "Who's afraid of il-liberal hegemony (Part 2)", this is a response to a comment from Paul.

I realise quantum chromodynamics, like all other branches of modern theoretical physics, takes training to do properly, and a relatively high IQ. I know that in one or two cases, these activities generate actual testable predictions which agree with observed data. (In the case of quantum electrodynamics — Richard Feynman's claim to fame — allegedly the best agreement with data of any theory ever.)

Nevertheless, I'm sceptical of the whole of post-quantum theory (I know, how dare I) in the sense that (a) I'm not convinced these theories are really internally self-consistent, (b) parts of the associated theoretical apparatus strike me as being there for show. I.e. they look clever, but do they really amount to anything?

It's all a little reminiscent of the theory of epicycles, the prevailing model of astronomical phenomena at the time of Copernicus. There's a plethora of theoretical devices, the thing kind of works, but it's somehow highly unsatisfactory. Perhaps only on aesthetic grounds, but that may be quite a useful criterion. (Einstein thought so.)

Now with regard to physics, my scepticism about the theoretical apparatus being at least partly vacuous is only a suspicion. In the case of economics, I have more in-depth experience and think this is definitely the case. The fact that there is a sort of "emperor's clothes" thing going on in economics makes me feel it's not implausible that it's also going on in physics.

Actually it’s not that much a case of “emperor’s clothes”. In the case of economics, I believe many of the people on the inside either know or suspect that they’re really playing a sort of intellectual game which isn’t necessarily meaningful, but which provides them with status and pays the bills. There is now, incidentally, a whole movement based on opposition to gobbledygook economics called the Post-Autistic Economics Network. I don't think they really have a handle on it, though, because they seem to believe the problem is that economics isn't oriented enough towards "social issues", i.e. it's supposedly not sufficiently left-wing.

When Schrödinger came up with the Wave Equation in 1926, he didn't even know what the central variable psi stood for (and we still don't really). I think physics since then has got worse, in the sense of generating mathematics whose only merit is that some of the time it produces testable predictions, and these usually sometimes work.