On Tue, Jan 07, 2025 at 05:55:50PM +1100, Bruce Kellett wrote: > On Tue, Jan 7, 2025 at 5:21 PM Russell Standish <[email protected]> wrote: > > On Mon, Jan 06, 2025 at 09:23:50PM -0800, Brent Meeker wrote: > > > No. He's not saying each bit sequence is equally likely. Probabilities > have > > not been introduced. He's saying that in every measurement of UP or > DWN, > both > > results occur per MWI, and so in N repetitions there will be N > occurrences of > > UP and N occurrences of DWN and this obtains independent of the > probability of > > UP. Then for every observer who sees p*N Ups then there will also be an > > observer who sees (1-p)*N UPs (by simple symmetry). > > But that simple symmetry only applies if you've included also those > observers who have rotated their apparatus -θ as well as those who > have rotated the apparatus θ. > > If you restrict the range of observers to just those who have rotated > the apparatus to θ (as Bruce does) > > > What makes you think that? >
That is per your description of the experiment. We're only considering those experiment where the apparatus has been rotated θ. In the Multiverse, all rotations are, of course, present in different worlds. If you sum over all of those, then of course the probability of seeing spin up is 0.5, and the Born rule likewise gives a value of 0.5. But in the setup you give, we're considering only those experimenters who have set a specific rotation of the the apparatus. Then the simple symmetry that you and Brent are relying on simply doesn't exist. -- ---------------------------------------------------------------------------- Dr Russell Standish Phone 0425 253119 (mobile) Principal, High Performance Coders [email protected] http://www.hpcoders.com.au ---------------------------------------------------------------------------- -- 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 view this discussion visit https://groups.google.com/d/msgid/everything-list/Z3zSPKIshySxpxx7%40zen.
