Friday, May 1, 2020

Simultaneity, A-Theory and Relativity

Here is a standard story about Special Relativity and the A-theory of time:

  • There is an objective metaphysical simultaneity, but

  • this metaphysical simultaneity does not affect physical events and is unobservable.

Let’s assume the A-theory is correct and this story is also correct.

Now, when people talk about this metaphysical simultaneity, they normally think they it aligns with the frame-relative simultaneity of Special Relativity for some privileged reference frame. This seems reasonable. But it is an interesting question to ask for an explanation of this alignment.

Causation may put some constraints on metaphysical simultaneity. For instance, perhaps, there shouldn’t be any possibility of future to past causation. But a metaphysical simultaneity relation can satisfy such constraints without coinciding with any frame-relative simultaneity.

If God exists, I guess we might suppose that metaphysical simultaneity coincides with a frame-relative simultaneity because it’s more elegant if it does.

1 comment:

Avraham said...

Things they just do not have classical values of time or position in space until measured. Because of Bell's inequality it could have been the case that things are simultaneous or that things do not have classical values. Since the first way is not true since we know that Relativity is right so the only thing left is the second.The actual case in hand was thought up by Einstein and it was Bell who showed the predictions of QM are different than classical mechanics. At any rate, we know that time is just this very odd kind of thing. It was already odd with special relativity. It just got even more odd with Bell. Kant thought that reason just can not understand it at all. But with Hegel there is hope since reason can make progress towards understanding.