actually if GR is completely correct than gravity could easily be describedas the curvature of spacetime, as that is exactly what GR says. To say that its wrong would be a bit unfair and to state that the new quantum theory will look nothing like it conceptually is not a good thing at all as currently there is alot of progress to nowhere in quantizing gravity and its quite likely that there will turn out to be something new in the future that still looks like GR just with some refinements, such as a quantized spacetime.

 

Unfortunately, string theory was supposed to solve this, but the original string theory had these nasty little buggers called tachyons, that moved faster then the speed of light, and caused the theory to be unstable.

 

However, the unification of supersymmetry and string theory, superstring theory, was a very nice, concept which also decreased the amount of dimensions from 26 to 10 or 11.

 

The problem is however, there is an infinite amount of these theories (with a negative or 0 cosmological constant) however, recently we have found the universe to have a small, but positive cosmological constant, which ahs reduced the amount of theories to around 10^500.

 

The only problem is every single one of those has either makes predictions that simply don't agree with what we see. Or, as what 99% of them do, they call for particles that have yet to be seen, and infinite range forces that have yet to be detected.

 

Unfortunately we have nothing anywhere close to a theory of QG, string theory was our best bet, and it was 30 years of fruitless study. We need to take a step back to the standard model and need to take it in a new direction.

vacuodynamic and my posts on unifcation etc... have been split to here:

 

http://www.scienceforums.net/forum/showthread.php?t=34443