There is still, to this day, absolutely no empirical proof that string theory is correct, or even that it can predict anything , but I know it's mathematically elegent ,here's feynman view on it:''I don’t like that they’re not calculating anything. I don’t like that they don’t check their ideas. I don’t like that for anything that disagrees with a n experiment, they cook up an explanation—a fix-up to say, “Well, it might be true.” For example, the theory requires ten dimensions. Well, maybe there’s a way of wrapping up six of the dimensions. Yes, that’s all possible mathematically, but why not seven? When they write their equation, the equation should decide how many of these things get wrapped up, not the desire to agree with experiment. In other words, there’s no reason whatsoever in superstring theory that it isn’t eight out of the ten dimensions that get wrapped up and that the result is only two dimensions, which would be completely in disagreement with experience. So the fact that it might disagree with experience is very tenuous, it doesn’t produce anything; it has to be excused most of the time. It doesn’t look right.'' –Richard Feynman I know this was before M-theory but I still think it's a little half-assed ....I really like it though and would be a string theorist If I had the chance to become a physicist ...but what do you people think?