> On 1 Aug 2018, at 06:19, Bruce Kellett <[email protected]> wrote: > > From: Bruno Marchal <[email protected] <mailto:[email protected]>> >>> On 31 Jul 2018, at 04:05, John Clark <[email protected] >>> <mailto:[email protected]>> wrote: >>> >>> On Mon, Jul 30, 2018 at 9:14 PM, Jason Resch <[email protected] >>> <mailto:[email protected]>> wrote: >>> >>> >> You and I have quantum entangled coins, I'm on Earth and you're in the >>> >> Andromeda Galaxy 2 million light years away. I flip my coin 100 times >>> >> and record my sequences of heads and tails and then just one hour later >>> >> you do the same thing. >>> >>> > It doesn't work like that. You need to generate the coins at one >>> > location, then bring them separately (at sub C speeds) from the location >>> > they were created to Earth and Andromeda. It's because of this that FTL >>> > is not not needed under QM to explain EPR. If it worked as you said then >>> > it would require FTL. But you can't keep flipping the same coin. >>> >>> >>> I was simplifying things to get to the essential difference between a >>> communication and a influence and you're just changing one apparently >>> random sequence to a different apparently random sequence and the only way >>> to tell that something funney is going on is when the two results are >>> checked sinde by side which can only be done at the speed of light or less. >>> But if you want exact then substitute the coins for 2 streams of 100 spin >>> correlated electrons created midway between Andromeda and Earth and replace >>> the coin flips for 2 Stern Gerlach magnets oriented the same way. >> >> >> If Alice and Bob are space-separated, and that they have not yet measure >> anything, how could they know (first person) that they are in the same >> branch? > > Very easily. They had coffee together beforehand. They were in the same > branch then, and have not jumped between branches in the meantime.
I can be OK with this, by the fact that they share a singlet sate, but they are ignorant of which one in particular. > >> How do you make sense on this if only locally? There is an infinity of Bob >> and Alice, > > No, there are not any infinities of anything. You simply confuse yourself by > continuing to claim such things which are not part of quantum mechanics. The singlet state just means that They will see correlated result when coming back together. Let me put it in this way: if Alice and Bob are space separated, I do not see how to give meaning to “to be in the same branche”, and they might individually get non correlated spin measurement? Bell’s inequality will not been violated, because that Bob and Alice will never meet again. Each of them will meet only their relevant counterparts when they will “meet again”. > > >> and all what they both know is that they share some historical reality with >> a relative partner, so that their simps are correlated, but they are are >> ignorant and thus distributed on infinitely many histories, with all the >> correlation between different spin “angle” (assuming a fixed base to >> describe them). >> I might be wrong, but the violation of Bell’s inequality (or Kochen-Specker >> theorem) does not entail any physical instantaneous action at a distance. I >> have seen may attempt to prove this, but they always favour a branch in a >> way or another, forgetting the probabilities bear on different portioning of >> the multiverse in the big picture. > > Any evaluation of a set of correlations between experimental results happens > in one branch of the superposition. So much for "favouring a branch in a way > or another." There is simply no other way to evaluate the correlations. There > is no "big picture" that is going to change this conclusion. Then you assume some collapse. > > >> It makes the whole physics becoming covariant, despite necessary relative >> local appearance of what seem to be an action at a distance. There are none, >> but to show this, we must take into account the fact that Alice and Bob find >> all correlated results in all directions. > > Physics is covariant in any case. The non-locality is real -- it is not just > an 'appearance'. Bell's theorem and the observed correlations prove this. I don’t see this. The violation of Bell’s inequality is real, but without any collapse, all interactions are local, and spread locally fro the place where they have been done. That follows from the wave only, and that guaranties that Alice and Bob, when coming back, will see the correlation/violation, but Alice and Bob does that only with some relative counterpart of Bob and counterpart of Alice respectively. Like Maudlin says: “Or finally once can both avoid collapses and retain locality by embracing the Many-Minds ontology, exacting a high price from common sense”. Bruno > > Bruce > > -- > 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] > <mailto:[email protected]>. > To post to this group, send email to [email protected] > <mailto:[email protected]>. > Visit this group at https://groups.google.com/group/everything-list > <https://groups.google.com/group/everything-list>. > For more options, visit https://groups.google.com/d/optout > <https://groups.google.com/d/optout>. -- 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 https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
