On Thu, Dec 14, 2017 at 9:20 PM, <agrayson2...@gmail.com> wrote: > > I don't see how Wigner's friend presents a problem for Copenhagen. > According to the CI, the wf collapses when the system measured, which is > when the box is opened. What am I missing? >
According to Copenhagen Wigner's friend opens the cat box and that collapses the cat's wave function, and so Wigner's friend now knows the cat's fate, but Wigner's friend is also in a box and Wigner himself is outside that box, so until Wigner opens his friend's box his friend is in a "I see a dead cat" state AND a "I see a live cat state". And of course you could put Wigner himself in a box with somebody outside it and you could keep increasing the number of nested boxes until the entire universe is included, and that is why the Copenhagen interpretation is useless if you're interest is in dealing in cosmology because there is nobody outside to universe observe it. And God is of no help unless somebody knows who collapses God's wave function, and even then there would be another unanswered question too obvious to mention. 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 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.