Tag Archives: Stamp Collecting

Physics Envy on a Cold Day

I read a post by a biologist philosopher about how supposedly physicists are undertaking “stamp collecting.” And I’m fairly annoyed that they missed the entire point. They read this article on attempted classification of string vaccua, and likens this attempt to taxonomy in biology, in their eyes lowering physics to a descriptive science. This whole flame war started with Rutherford claiming “In science there is only physics. All the rest is stamp collecting.” Let me liberally translate to clarify: “In science the only quantitatively predictive field is Physics, and everything else is descriptive.” This certainly was true in Rutherford’s time, but discovery of atomic structure elevated Chemistry to predictive, and the discovery of DNA elevated biology. Now we’re all buddy-buddy. In real science, 99% of the time you first gather data, then classify, then build models, and then you have a quantitative principle to make predictions. This went faster with physics because we deal with much more homogeneous systems. An old friend and ex-ZEUS student I know is now writing Monte Carlo simulations for Neuro Bio. That aint taxonomy. Heck, even economists have real models these days, and their particles have agency.

The big missed point is the following: String Theory isn’t predictive, or descriptive, yet. It has never made better than tenuous qualitative connection with reality, and I wouldn’t bet any money that it will improve soon. Why? Because its history is all bass-ackwards. It may have started from meson spectroscopy and QCD flux tubes in the late 60’s, but then everyone thought they smelled gravity and got the great idea to start from a unprobeable scale and grope their way back down to experimentally plausible energies. In string theory you first assume an underlying principle, then build a phenomenological model, then gather data. This isn’t to say its totally unmotivated, but it does incur a large investment risk.

The authors whole point is that stamp-collecting is a type of science, and shouldn’t be looked down on. This is half true. It is necessary for developing falsifiable theories, but should not be considered a form of science in itself. People can gather data, and arrange it in clever ways, but without predictions and basic principles, There’s very little objectivity, or application.

So biology in Rutherford’s time was like stamp collecting, but all those stamps they collected were issued from a genuine authority. Woit claims the String Vaccua Project “…is stamp-collecting done by people who don’t have any stamps, just some very speculative ideas about what stamps might look like.” He breakdown of the string vaccua project on his blog, if you want to read more. He also comments on the original biologist’s philosopher’s post.

Edit: Dr. John S. Wilkins, the author of said blog, is a postdoctoral research fellow of philosophy, not biology, as originally stated.

Advertisement