They're looking for a 'theory of everything' trying to reconcile realtivity with string theory (or something along those lines). Its absolutely fascinating. I have watched the program for lay people and while you watch it you 'kind've' understand it, but really at the end of the day the stuff these guys is saying borders on the esoteric.
The first time you heard about 'time dilation' don't even tell me you weren't even a little bit perplexed.
Yes, they have proven it, the laws of physics apply equally in any inertial frame, but humans PERCEIVE a world where it would make more sense for clocks to be a constant....ie. I perceive a second, you perceive a second (no matter what your velocity!)
I love it when they begin speaking about massive objects like the sun and black holes and how they warp space time and how lights bends around the sun (and again they have proven it), but it still makes you wonder - warping into what exactly?
Well, let's hope they don't manufacture a black hole which swallows us up!