These days some of the strongest criticisms of what is going on in string theory are coming from Lubos Motl’s weblog. His latest post asks what would have happened if currently fashionable ideas about string theory had appeared in the sixties before the standard model. They would have led to claims that many things about particle physics were inherently unpredictable, or dependent on the details of the earliest moments of the big bang. But when the standard model appeared in 1973, it made a wide range of detailed predictions of this type.
He also makes some remarkable statements about string dualities:
“Virtually all conjectured non-supersymmetric dualities (except a few exceptions in the topological context) are suspicious, and even those that are true may be true only because we define one of the sides to be dual to the other – while other equally consistent definitions may exist, too.”
and claims that in the mid-90s Tom Banks described how research on string dualities was being done as follows:
“If you can’t show that a conjectured duality is wrong in 5 minutes, it must be correct.”
Funny, I’d always suspected that was what they were doing, but I’d never have dared to suggest it. And by the way, I’m wondering if Jacques Distler has given up on string theory. It’s been several months since he’s written anything about strings, and a month since he’s written anything at all.