> On 2 Aug 2018, at 16:38, John Clark <[email protected]> wrote: > > > > On Wed, Aug 1, 2018 at 11:46 AM, Bruno Marchal <[email protected] > <mailto:[email protected]>> wrote: > > >>If a unmeasured electron or any particle (the exparament was originally > >>done with silver atoms) passes through a Stern Gerlach magnet the particle > >>will be deflected up (relative to the orientation angle chosen to set the > >>magnet at) or down 50% of the time. And if 2 electrons are quantum > >>correlated and one is found to be deflected up then there is a 0% chance > >>the other electron will also be deflected up. The really weird thing is > >>that the direction I chose to be called "up" was completely arbitrary, I > >>could have picked anything from 0 degrees to 360 degrees, and yet it's > >>brother electron seems to instantly know what angle I chose to call "up" > >>even though they are now 2 million light years away and the brothers were > >>last in physical contact with each other a million years before I was born. > > >this is because the state has been prepared (locally) in this way. The ud - > du singlet sate can be written u’d’ -d’u’, for all other bases. The singlet > state ud - du means that Alice and Bob have the same or opposite > spin/polarisation and are correlated, but neither Alice nor Doc know in which > direction. All they know is that there is a correlation. When Alice measure > her spin, suddenly she knows in which “universe” she is, and she knows that > if she met Bob again, he will indeed have the opposite result. With one > unique world, we cannot explain this without FTL influence, > > I don't have any big disagreement with that.
OK. It looks like Bruce disagree with this, but I am not sure why or how. > > >but with the "many-world” we are back at a Bertlmann socks case. The same > >for the Bell’s inequality violation. They are not violated in the wave, but > >the wave explains that in each branch the Bell’s inequality is violated, and > >if they believe in only that branch, they have to believe in FTL, but if > >they take all branches into account, I don’t see the need to invoke any FTL. > > The problem is neither FTL influences nor the creation of Many Worlds > violates the know laws of physics FTL influences violate any minimally realist account of Special Relativity. It reintroduce a universal time and a notion of instantaneity which makes few sense in relativistic cosmology. There is no instrumental violation, but that is the case of the fact earth theory too. > and both theories agree with all known experimental results equally well, so > how can one decide which one is correct? Until we get better data from some > new astronomical observation or exparament it all comes down to personal > incredulity; both you and I feel that although strange Many Worlds is less > strange than the alternatives, but others may feel differently. And who knows > maybe they're right, I doubt it but I've been wrong before. In science, we can always been wrong. But some theories can be more plausible than other. I would say that any theory which introduce 3p indeterminacy and 3p physical FTL is less plausible than a theory which manages to make the same predictions (including the violation of Bell’s inequality) without introducing 3p indeterminacy and non locality without any means to test it. Bruno > > John K Clark > > > > -- > 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.
