A couple people this morning pointed me to today’s press release from Imperial College, headlined Researchers Discover How to Conduct First Test of “Untestable” String Theory and subtitled “New study suggests researchers can now test the ‘theory of everything'”. In case you miss the headline and subtitle, and thus the point that string theory is now testable due to the efforts of Imperial College researchers, the rather short press release repeatedly drives the point home:

The new research, led by a team from Imperial College London, describes the unexpected discovery that string theory also seems to predict the behaviour of entangled quantum particles. As this prediction can be tested in the laboratory, researchers can now test string theory… Using the theory to predict how entangled quantum particles behave provides the first opportunity to test string theory by experiment… The discovery that string theory seems to make predictions about quantum entanglement is completely unexpected, but because quantum entanglement can be measured in the lab, it does mean that at last researchers can test predictions based on string theory…

There’s a blog posting written about the preprint of this paper when it first appeared here, in which I pointed out that the result worked out in the paper is just an example of a well-known piece of mathematics that comes down to classifying nilpotent orbits. This is based on a famous 1971 theorem of Kostant-Rallis, and Nolan Wallach worked out in detail here the specific example considered by Duff et al. in lecture notes for a 2004 summer school. The initial preprint didn’t refer to this mathematical literature, but a revised version was soon issued in which a reference to the Wallach notes was added to the bibliography. There’s no trackback to the discussion on Not Even Wrong at the arXiv listing for the paper due to the arXiv’s censorship policy, but perhaps one or more of the authors of the preprint are regular readers here…

I have no idea how this paper is supposed to contain a “test” of string theory. The simple quantum mechanics problem at issue comes down to classifying orbits of a group action on a four-fold tensor product, exactly what Wallach worked out in detail in his notes, as an example of Kostant-Rallis. If you do an experiment based on this and it doesn’t work, you’re not going to falsify string theory (or Kostant-Rallis for that matter). By now there’s a long history of rather outrageous press releases being issued about the discovery of supposed “tests” of string theory. This one really takes the cake…

Update: The press release is having its intended effect, generating stories headlining false claims about string theory . So far today, there’s String Theory:Testing the Untestable?, New study suggests researchers can now test the ‘theory of everything’, Scientists Say They Can Now Test String Theory and Researchers Devise the First Experimental Test of Controversial, Confusing String Theory. There’s even UK Scientists discover way to test untestable string theory, which has the test already performed:

Scientists at the Imperial College London have managed to conduct the first string theory test, destroying previous beliefs that it was untestable…. The discovery will please physicists, most of whom consider string theory the best available for explaining the universe.

Unfortunately, no details on how the test turned out…

Update: The subtitle on the press release has been changed. It used to be “New study suggests researchers can now test the ‘theory of everything'”, now it’s “New study presents unexpected discovery that string theory may predict the behaviour of entangled quantum particles.”

Update: No press campaign for a “finally string theory is testable” claim is complete without a Slashdot story (actually, stories, here and here):

Big news for theoretical physicists who are fed up with the inability to test String Theory…

Update: Lisa Grossman has a story about this at Wired Science. She went to the trouble of contacting well-known string theorists for their opinion, which is unanimous that this is not a “test of string theory”:

“Already I can imagine enemies sharpening their knives,” Duff said. And they are. A chorus of supporters and critics, including Nobel laureate and string theory skeptic Sheldon Glashow and string theorists John Schwarz of Caltech, James Gates of the University of Maryland, and Juan Maldacena and Edward Witten of the Institute for Advanced Study in Princeton agree that Duff’s argument is “not a way to test string theory” and has nothing to do with a theory of everything.

I’m still trying to figure out what the supposed test of string theory is, since I can’t find such a thing in the published paper. The Wired article has a bit more explanation from Duff:

Whether the result is some fundamental principle or some quirk of mathematics, we don’t know, but it is useful for making statements about quantum entanglement.

As far as I can tell, we do know where their results come from, a “quirk of mathematics” known as the Kostant-Rallis theorem, applied to the invariant theory question that comes up in quantum entanglement.

The article also contains quotes from me, saying about what you’d expect.

Update: Science News has completely uncritical coverage of the “First Test of String Theory” claims.