A recent issue of Science magazine has an article about the “Strings and the Real World” workshop at Aspen this past summer, entitled String Theory Gets Real — Sort Of. A more accurate title for the article might be “String Theory Would Like to Get Real — But Can’t Because it Doesn’t Work”.
The article claims that up until recently string theorists were not even trying to connect string theory with experiment, but “Now a small but growing number of them are trying to forge connections between string theory and detailed data”. This is really nonsense. There have always been plenty of people doing “string phenomenology”, but it has always been a doomed subject, for reasons I’ve gone on about at length here and elsewhere. The article does mention the problem of the Landscape with the increasingly standard loony comment that “physicists may have to rethink what it means for a theory to explain experimental data”. This is absurd. There’s no question about what it means for a theory to explain experimental data and the simple fact of the matter is that this theory can’t do it.
There’s also a claim that “the cosmological constant now appears to be real, and string theorists hope to calculate its value”. This misunderstands the whole Landscape argument, which tries to justify why no one can ever hope to calculate this value.
The article also includes a sidebar which tries to explain why young people go into string theory. It quotes a Penn postdoc, Brent Nelson, as saying that he read about string theory as a teenager and couldn’t believe so many people accepted something so outlandish. But he went into string theory anyway, and now says “I haven’t learned enough… I still don’t know why I should believe”. Sorry Brent, but no matter how long and hard you stare at this particular emperor trying to appreciate the beauty of his clothing, he’s still going to be naked as a jaybird.
Finally, when asked how many revolutions will be needed to make string theory work, John Schwarz says “I don’t know, but I think we’ll need many more”. At about a decade per revolution, it looks like Schwarz now doesn’t expect to live to see this happen. Neither do I.