I am completely new to Google Groups, and so I hope you may understand if my intrusion here is inappropriate or if I break any protocols in replying to this topic. I came across this Group while searching for a paper.
I was very taken by Pierz’s first statement, as it reminded me of my own agonies over the seeming incompatibility between (1) the block universe where all events (some of which we perceive as “in the future”, depending upon our motion relative to the events) are “frozen” into the space-time fabric, and (2) quantum uncertainty about future events. (In case any of the many physicists who do not accept the block universe are reading this, perhaps I can refer them to “Proposal for an experiment to determine the block universe” (http://arxiv.org/abs/1603.08959) in which the Mars Reconnaissance Orbiter will play a key role…) Quantum uncertainty, of course, is fundamental in that there are events whose outcomes cannot be predicted with 100 per cent certainty in this universe. Pierz is on the right track in saying that the Many-Worlds model may address this uncertainty, changing the question to one of uncertainty over which branch of the Many-Worlds tree one is in. (Of course, we inhabit many “parallel” branches, although each version of us perceives ourself to be unique.) The difficulty with the Many Worlds Interpretation has always been that branching is incompatible with the block-universe model. How can a block universe have branches? The proposal of this paper – http://arxiv.org/abs/1602.04247 (“Some remarks on the mathematical structure of the multiverse”) and described more completely in http://arxiv.org/abs/1609.04050 (“A discrete, finite multiverse”) – gets round that difficulty. Each branch of the Many-Worlds tree comprises many (but not infinitely many) “filaments”, each extending from the trunk to the topmost twig. Each one of these filaments is a block universe. Events in these universes tend to be similar towards the trunk and tend to diverge as one proceeds up towards the thinner branches. Of course, this hypothesis only makes sense if the multiverse is purely a system of mathematical relations, in the Tegmark sense. (However, Tegmark’s model is ultimately incompatible with the hypothesis: see, for instance, the discussion in http://www.godel-universe.com/tegmark/). On Friday, May 26, 2017 at 2:30:07 AM UTC+1, Pierz wrote: > > Recently I've been studying a lot of history, and I've often thought about > how, according to special relativity, you can translate time into space and > vice versa... > -- 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 https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
