Wikipedia article: http://en.wikipedia.org/wiki/Rietdijk–Putnam_argument
Abstract of 1966 Rietdijk paper:
A proof is given that there does not exist an event, that is not already in the past for some possible distant observer at the (our) moment that the latter is "now" for us. Such event is as "legally" past for that distant observer as is the moment five minutes ago on the sun for us (irrespective of the circumstance that the light of the sun cannot reach us in a period of five minutes). Only an extreme positivism: "that which cannot yet be observed does not yet exist", can possibly withstand the conclusion concerned. Therefore, there is determinism, also in micro-physics.
I realize that this is a very philosophically-heavy topic, but at the same time, it is physical in the strictest sense (in that it's not a "What if" question, but more of a thought experiment, like the Twin Paradox, that follows the logical implications of relativity to some extreme scenario).
So, setting aside matters of "free will" and whatnot, which I'm not interested in...
If I understand this article correctly: the content of these papers implies a 100% deterministic universe — one in which the future of any object is "set in stone"; but, at the same time, this future is completely inaccessible to any observer that is in its past (i.e: impossible to predict even given initial conditions, because of small-scale uncertainty, chaos, etc.).
Are the proofs in these articles are well-accepted? (Meaning that this "everything has already happened depending on the observer" universe is the only conclusion one can arrive at?).
I was not aware of the Andromeda Paradox before. I can't imagine it being very useful, but it's interesting enough as a mind-bender that I'd've thought one would hear about it more often.