On Monday, April 9, 2018 at 7:26:43 AM UTC-5, Bruno Marchal wrote: > > > On 9 Apr 2018, at 00:48, Lawrence Crowell <[email protected] > <javascript:>> wrote: > > On Sunday, April 8, 2018 at 11:25:39 AM UTC-5, Bruno Marchal wrote: >> >> >> On 5 Apr 2018, at 22:20, [email protected] wrote: >> >> Assuming that QM is a non-local theory, if two systems become entangled, >> say via a measurement, do they necessary have a non-local connection? That >> is, does entanglement necessarily imply non-locality? AG >> >> >> As Everett already understood, non-locality is itself phenomenological. >> But the violation of Bell’s inequality makes any mono-universe theory >> highly non-local. It is my main motivation to be skeptical in any >> mono-universe theory. >> >> Some, even in this list, believes that in the many universe theory there >> are still some trace of no-locality, but generally, they forget to use the >> key fact, explains by Everett, that observation are independent of the >> choice of the experimental set up. In particular, a singlet Bell’s type of >> state, involves really a multi-multiverse, somehow. Better not to take the >> idea of “universe” to much seriously, as in fine, those are local first >> person plural relative states, and they emerges already from elementary >> arithmetic, in a way enough precise to be compared with the facts. >> >> Bruno >> > > > This sounds confused. There is noncontextuality in QM that states there is > nothing in QM that determines how an apparatus is to be oriented. > > > OK. > > > This is in ways thinking if the Stern-Gerlach apparatus, where its > orientation is a choice of basis vector. QM is invariant under choice of > basis vectors. The context of the experiment is then due to the classical > or macroscopic structure of the observer or apparatus. > > > It seems you are saying the same thing as me. > > But this does not entails any physical action at a distance, unless we > postulate a physical collapse of the wave (as opposed to a local > entanglement relative to the observer, which is local and which propagates > only at the speed of light. Then when Alice (say) measures its particle, it > only tells Alice in which partition of the multiverse she belongs, and > where indeed Bob will find the corresponding results. EPR and Bell assumes > a mono-universe to get the non locality. > > Bruno >
I don't have any serious objection with this. I though do not in thinking about these things invoke quantum interpretations if possible. If I do I often might appeal to a couple of them, usually MWI or Everett's and CI of Bohr, to illustrate two ways of thinking. There is also the Montevideo interpretation that takes off from Penrose's idea of gravitation and R-process. However, I don't particularly believe in any of them. LC -- 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.
