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Join Date: Jul 2003
Location: FL
Posts: 5,545
My Ride: Yukon

Asking what is vibrating is like asking through what does a light wave propagate, or, What is the aether? I still have a hard time wrapping my head around the fact that spacetime isn't a physical entity, per se, but a metric of curvature. It is a purely mathematical construct, like a wavefunction. I started a fairly lengthy discussion on the physics forums with that very question and it seems there still isn't a definitive answer outside of the mathematical description. Well, it actually started with me asking just what light really is, but that led to a discussion on spacetime.
http://physicsforums.com/showthread.php?t=510107
