And on a unrelated note, I have a question about simulataneous events in relativistic frames of reference. A few years ago, we talked about the seemingly paradoxical nature of the old "ladder speeding through a barn" problem. And how the differing sequence of events in the two frames of reference resolve the question of what happens (or is seen to happen) when the ladder is (is not) fully within the barn, and the barn doors are closed. Namely, in the barn's frame of reference, the doors may be closed simultaneously around the ladder (enclosing it) and the ladder is seen to bursts through the far door, while in the ladder's frame of refernence, the door (not yet behind it) is still open while the ladder blows throught the closed door ahead of it, therefore never being enclosed by the barn. Here's my question: What if some third event is contingent on two events (say the closing of the two doors) occuring simultaneously. In the barn's frame of reference, this third event would occur, while in the ladder's frame of reference it would not. My suspicion is that any experiment which I could set up to point out this paradox would require some kind of "spooky action at a distance." What do you think?
Nevermind, I think I had a revelation in the shower just now (or the retrieval of a suppressed memory from undergraduate days) that simultaneity in time, without consideration of location, is meaningless.