Hi Liz, Great avatar :)
On Sun, Feb 2, 2014 at 10:44 AM, LizR <[email protected]> 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. This would presumably be external to > the 4D manifold, so it would require a 5D "space-time-time" manifold in > which to operate. This seems like a crypto-religious viewpoint. The > assumption is that a universe has to be created, and even created / > sustained at every moment of its existence - rather as Newton imagined God > keeping the planets in their orbits (he worked out that they were unstable > over the long term, I believe). In this view a 4D space-time can't simply > exist due to some logically prior cause. Yet assuming it has to "come into > existence" within some external time merely pushes the question back a step > - the time within which the BU is created can also be viewed as a BU, with > one more time dimension, so one then has to ask how that BU came into > existence - and so ad infinitum. This is a very good point. > This worked rather nicely in Isaac Asimov's novel "The End of Eternity" (in > which he posited a multiverse and an external time running across it, so his > "Eternals" could change history and effectively move across the multiverse > to a new history in their search for a perfect society). But it seems > unnecessary from a scientific viewpoint, and of course runs foul of Occam's > razor. Couldn't the same be achieved through quantum suicide, even without and external timeline? Cheers, Telmo. >It's possible, of course, but there is no evidence for it (and I > can't offhand imagine what such evidence would be). It seems to me more > sensible to try to explain the existence of space-time by positing something > simpler, from which space-time emerges. Most current approaches to quantum > gravity use this approach, I believe. > > Otherwise, one is just explaining space-time in a circular manner, by > requiring the existence of what you're trying to explain - another time > dimension - and, in fact, an infinite number of them, if one takes this idea > to its logical conclusion ("It's time-tles all the way down...") > > -- > 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 [email protected]. > To post to this group, send email to [email protected]. > Visit this group at http://groups.google.com/group/everything-list. > For more options, visit https://groups.google.com/groups/opt_out. -- 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 [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/groups/opt_out.
