The Only Game in Town

Warning: if you follow this blog, you’ve heard this many times before, so can move on to something more interesting now. There’s a video conversation between Brian Greene and Lenny Susskind from last week here. At 44:02, Susskind has this to say: One of the chief critics is a colleague of yours, I believe. And he is rather forcefully maintaining that string theory, until it can produce a success of the kind where you actually can produce a number and that number can be checked with experiment, that it doesn’t have any value. The main reason for this post is just to reiterate that this is not what I think. The problem with string theory as a unified theory is not that it hasn’t made a tested prediction, but that it has made no predictions, of any kind. It’s very clear now that, as a theory of the real world it’s a speculative idea that just doesn’t work. As to whether it has “any value”, you have to first define what “string theory” is. Under some definitions there are things of value,…