The Unraveling of String Theory

This week’s Time magazine has as article by Michael Lemonick about the controversy over string theory entitled The Unraveling of String Theory. It mentions my book and Lee Smolin’s, and there’s a quote from Sean Caroll. There’s the usual hysterical reaction from Lubos Motl: Time Magazine: Physics is a Sin.

Lemonick more or less gets the story right, describing the reaction of string theory critics to the landscape as:

It was bad enough, they say, when string theorists treated nonbelievers as though they were a little slow-witted. Now, it seems, at least some superstring advocates are ready to abandon the essential definition of science itself on the basis that string theory is too important to be hampered by old-fashioned notions of experimental proof.

Lemonick describes both Smolin and me as having worked on string theory. Smolin has done original research on the subject, but I certainly haven’t. I don’t agree at all with Sean Carroll that the problem is that not enough string theorists “take the goal of connecting to experiment more seriously”. Many of them take it very seriously, but the fact that it is a failed idea that doesn’t work is what has forced them into the landscape nonsense and other complicated, unworkable schemes.

The quote from me is a little bit out of context. I was making the point that physicists necessarily often start out with speculative ideas that are “not even wrong”, in the sense that they are so poorly understood that one can’t tell where they will lead, and that this is very much legitimate science. On the other hand, once a theory is well enough understood to see that you can’t use it to make predictions, if you keep pursuing it, you’re not doing science anymore.

Update: Tomorrow on Science Friday Ira Flatow will have Brian Greene and Lee Smolin on to discuss string theory. The September issues of Scientific American and Discover magazines have book reviews of Smolin’s book and mine. The Discover review is by Tim Folger and entitled Tangled Up In Strings; it begins:

In the mood for some no-holds-barred gossip or a nasty screed? Then start browsing the physics blogosphere, where some exceedingly smart people are spending an inordinate amount of time belittling one another. Alas, even this magazine has come under attack. The cause of all the commotion? Some nervy upstarts are questioning the validity of string theory, which is to physics what Wal-Mart is to retail: the biggest thing around, dominant for more than 20 years now. And woe unto anyone who doubts the orthodoxy….

The Scientific American review is by George Johnson and entitled The Inelegant Universe. Johnson notes one of his pieces for the New York Times six years ago carries what he now sees as an embarassing headline: “Physicists Finally Find a Way to Test Superstring Theory” (in his defense, this kind of headline is still appearing in over-hyped articles about string theory to this day). I’ve been a bit surprised at how friendly a reception Smolin’s book and mine have been getting so far from science writers. I think one reason for this is that many of them have repeatedly over the last twenty years written articles about string theory that repeat a lot of the hype promising imminent success in producing predictions. They’ve now been burned too many times and are very open to listening to the critics.