Monday, February 16, 2009

String Theory Predicts an Experimental Result?

A rather fascinating item that came out of the 2009 AAAS Meeting in Chicago. A panel discussion during one of the session presented a possible explanation out of String Theory that could describe two very widely separated experimental observations from 2 very different field of study.

First came out of condensed mater from the observation of the behavior of supercooled lithium 6, producing a strongly interacting Fermi gas that behaves like a superliquid. The second came from nuclear physics with the observation of the quark-gluon "liquid" from collisions at RHIC.

It appears that a claim has been made that the holographic principle of String Theory can produce a description that mimic these two phenomena. So in essence, you have the convergence of condensed matter, nuclear physics, and string theory.

So does that mean that string theory finally has an experimental verification? Hardly.

Not to say that string theory has been proved. Clifford Johnson of the University of Southern California, the string theorist on the panel, was very clear about that. All the arguments about whether nature is composed of unimaginably tiny vibrating strings and multiple dimensions, and whether this will eventually explain the basic workings of the universe, are still unresolved.

Furthermore, we also do not know if there aren't any other better explanations, i.e. is the string approach really unique? After all, condensed matter theory already has a well-established line of formulation for the Fermionic gas. If string theory claims to have a more fundamental theory, then it will have to reproduce all of those other observations as well, and not just this.



Ben Lillie said...

As I recall, there was a big paper a few years ago contesting the claims that string theory has a particularly good description of the QGP. They compared the holographic model to other, more traditional QCD models, and found it had decent, but far from spectacular agreement. Sort of middle of the pack.

Sadly, I can't find the reference right now; and, of course, it a few years out of date.

Hadronic Chaos said...

I listened to a lecture by John Harris from Yale last year on this subject. From what I recall, the holographic principle is used to form a duality between the thermodynamics of a quark-gluon plasma and a black hole in a certain form of string theory. In no way is String Theory predicting anything; its the math developed to explore string theory that is useful.