On 3 February 2014 08:03, meekerdb <meeke...@verizon.net> wrote: > On 2/2/2014 1:44 AM, LizR wrote: > > Someone asked how a block universe "comes to exist" and if it comes into > existence "all at once, or a bit at a time" (or something like that). > > I wish I could find the original question, to make sure exactly what it > was. But I haven't managed to find it, and I can't spend all night trawling > the forum for it, so I will just put my take on the matter here. > > Assuming I've got it right, this seems to me a rather odd question. > Asking how a block universe comes into existence presupposes that this is a > process that must happen within a time stream. > > > I can imagine a semi-block universe in which, as you've often remarked, > the past is a block and the universe keeps adding new moments and growing. > This would be like Barbour's time capsules, except just sticking everything > into one capsule, like a history book that keeps adding pages. But yes it > implies another exterior "time" in which this "happens"; but then so does > Bruno's UD. >
I don't think Bruno would agree with that. I think the UD is supposed to function simply by existing, and each state is defined relative to another one....somehow. (But at this point my brain melts...) > > My point is that we needn't take these models seriously. We just use them > to try to picture things. > > Right.... maybe.... not sure what you mean. That is, I'm not sure where the line is between which models one should take seriously (if any) and which ones are "just for picturing". Did Minkowski take space-time seriously? Does it matter? I thought the important things were prediction of (preferably unexpected) consequences, and being open to refutation. I assume as we get more into interpretation and general meta-ness, refutation comes to rely more on logical inconsistency or similar meta-refutations. But things can occasionally be "de-meta-ised" as our knowledge improves. This happened for block universes with SR. The experimental evidence for space-time being a 4D manifold is the relativity of simultaneity. I assume that before this, the concept was "just an interpretation" - it was the only picture that made sense of Newtonian physics, but (apart from thought experiments like "Laplace's godlike being") it was not considered experimentally testable. You just had to accept it on logical grounds (or posit extra time streams). Then along came Einstein, and showed that it *was* experimentally testable after all. I guess it's possible the MWI will undergo a similar "demetaisation" at some point, perhaps if quantum computers factoring very large numbers become commonplace... -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/groups/opt_out.
