из FAQ от A. Garrett Lisi
http://fqxi.org/community/forum.php?action=topic&id=107
-Question 7: You mentioned that you weren't interested in working on string theory? What advantages does your approach have over rival theories, such as string theory, both in terms of what it can explain, and also aesthetic appeal?
There are lots of good things about string theory. It appears to be quantizeable, and can accommodate gravity in a fairly natural way. It also has restrictions that come out, due to anomaly cancelation, that say what can and cannot be a "good" quantum string theory. Originally people thought this would be enough, when coupled with the right background manifolds, to get all the standard model particle fields to correspond to oscillations of a string. But it's never worked quite right. In order to get it to work at all, string theorists have to bend over backwards and put in all sorts of things by hand. This is the main warning sign that a theory doesn't correspond to nature. What happens is, a theory looks promising, so people invest time in developing it. If it looks like it's matching nature, that's great. But if it doesn't quite fit nature, people have already invested a lot of time in the theory, so instead of abandoning it, they try to revise it -- they add stuff and try to patch it up. But the more you have to add by hand, without any experimental guidance, the worse the theory looks and the less likely it is to be true about how nature works.
I suspected at the end of the 90's that string theory had left nature behind, and was going off in its own direction without any connection with reality. And it wasn't spreading out in a proper search either, it was barreling along in one direction like a freight train, guided by a handful of theorists with many followers who were devoting their lives to the theory. I've never been much of a follower, so I walked off to search on my own.
