> On 20 Aug 2018, at 01:23, Bruce Kellett <[email protected]> wrote: > > From: <[email protected] <mailto:[email protected]>> >> On Sunday, August 19, 2018 at 11:36:47 AM UTC, Bruce wrote: >> From: Bruno Marchal <[email protected] <>> >>> Yes. My feeling is that you do introduce some preferred base. >> >> Yes, your feelings are very much at fault here. If you thought a bit rather >> than go with feelings, we might be better off. I do not introduce a >> preferred basis. Where do you think I do that? You argue against a straw >> man, as usual. A typical base is not a preferred base. >> >> Since you could have chosen u - d and u + d as the basis, cannot u and d be >> considered a preferred basis? AG > > The (u-d), (u+d) base is just a 90 degree rotation of the u,d base. It could > be relevant if you oriented your magnets that way rather than in the u,d > direction. As usual, Bruno has muddied the waters here by introducing the > idea that |u> and |d> form a preferred basis.
Only for those who interpret ud-du as a superposition of ud and du, when it describes an infinity of superposition possibles. That is the problem with the tensor product: the same state describes different superposition possible. I still have no idea of your MW interpretation of the singlet state. Each time you give it, it seems to refer to some collapse, or to chose a “typical" base. (Your patronising tone does not help) Bruno > That is not the case, because the usual "preferred basis problem" of the MWI > concerns the stability of any particular basis under environmental > decoherence. Here the basis is chosen according to the orientation of the > magnets -- there is no idea of preference under decoherence involved; the > only consideration is that the basis in the direction of the magnets is the > one in which you can most easily make verifiable predictions. You could work > in some other basis if you are so stupid, but that has no effect other than > to complicate you calculations. It would not affect the physics. > > 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.
