Well, there's plenty of experimental evidence for both. If you've got a GPS receiver they must both be correct, otherwise it wouldn't work. It's a very good question and I can't answer it. The best I can do is suggest that there will be a fiendishly complicated (mathematically, that is) synthesis of the two. I suspect that a computer of superhuman intelligence will be needed to construct the theory of everything that replaces quantum, special and general relativity.
