I've been recently looking into an old physics topic: Mach's Principle: http://en.wikipedia.org/wiki/Mach%27s_principle. The basic idea is that rotational motion (and inertia) or NOT relative, but must be with respect to a fixed frame of reference, namely the "fixed" stars of the universe. Furthermore, the field of this force extends instantaneously from all massive bodies, NOT at the speed of light. This means that (according to our human way of thinking about things) stars who's light only now comes to us from billions of years ago somehow "know" the positions of rotating bodies now. The real now (???), not the now of billions of years ago. This looks suspiciously like the "spooky action at a distance" which Einstein objected to in quantum mechanics. He thought that quantum mechanics must either be wrong or incomplete, because the "wave function" at the heart of QM extended over both time and space. This doesn't seem to cause problems for the tiny scale at which quantum mechanics routinely functions, because the times are so short. What's a trillionth of a second here or there? But tabletop interferometry experiments of recent decades (quantum erasure for example, which you can actually do at home with a laser pointer and polarizers!) require this to operate at human time scale and longer. And this has been confirmed by experiment to be true. If you made one arm of your tabletop interferometer really really long, like the distance to a nearby star, it must still work. A "moment" in quantum mechanics can somehow extend across any number of years! Are these two spooky actions at a distance related? One is gravitational, and the other quantum mechanical. And remember that theoretical physicists are still trying to unite gravity and quantum mechanics into a single "theory of everything," and so far they have failed! Spooky, huh?