> On 17 Feb 2020, at 23:46, 'Brent Meeker' via Everything List > <everything-list@googlegroups.com> wrote: > > > > On 2/17/2020 2:11 AM, Bruce Kellett wrote: >> On Mon, Feb 17, 2020 at 6:04 PM 'Brent Meeker' via Everything List >> <everything-list@googlegroups.com <mailto:everything-list@googlegroups.com>> >> wrote: >> On 2/16/2020 9:48 PM, Bruce Kellett wrote: >>> On Mon, Feb 17, 2020 at 4:13 PM 'Brent Meeker' via Everything List >>> <everything-list@googlegroups.com >>> <mailto:everything-list@googlegroups.com>> wrote: >>> >>> But exactly the same reasoning applies for any given true value of p. >>> There will be different estimates by different experimenters and they can't >>> all be right. Each will infer that any proportion other than the one he >>> observed will have zero measure in the limit N->oo. >>> >>> Exactly right. That is what my example of spin measurements on an ensemble >>> of equally prepared spin states comes into play. If all 2^N bit strings are >>> realized for one orientation of the S-G magnet, then exactly the same 2^N >>> bit strings are realized for every other orientation. >> >> ?? Suppose the ensemble is equally prepared in spin-up. What does it mean >> to say all 2^N bit strings are realized for the S-G oriented left/right? We >> may expect they will be for any number of trials >>N. But certainly not >> for the S-G oriented up/down. >> >> I think we are beginning to argue at cross-purposes, and I may not have >> understood you correctly. Let me try to restate the position clearly, and >> see if you can agree. >> >> Take a spin-half state, and prepare a linear combination in the x-basis: >> >> |psi> = (alpha*|x-spin up> + beta*|x-spin down>), >> >> where we assume that neither alpha nor beta is equal to zero. We can now >> measure this state in the x-direction and assume Everett, so that every >> result is obtained in a separate branch on every trial. Coding these results >> as zero and one, a run of N experiments will give 2^N binary strings of >> results, consisting of the set of all 2^N binary strings of length N. Now >> rotate the S-G magnet from the x-direction by, say, 10 degrees. Your results >> are again the set of all binary strings of length N. Similarly for any other >> angle (except those for which alpha or beta rotates to zero). Since the set >> of results is the same in all cases, even though rotation of the S-G magnet >> is equivalent to changing alpha and beta in the superposition, the >> individual sets of results must be independent of alpha and beta. However, >> the Born rule states that the probabilities depend on |alpha|^2 and |beta|^. >> But we have seen that the many-worlds data are actually independent of alpha >> and beta. The Born rule for probabilities is thus disconfirmed in this >> Everettian case. >> >> That is the crux of what I am trying to get across -- Everettian QM is >> disconfirmed by experiment, since experiments show results that depend on >> the coefficients alpha and beta, in accordance with the Born Rule. There are >> other points that I have been making, but let's get this straight first. > > Yes, I agree with that. It's another way of expressing my objection that > while alpha=0.5 produces a split into two worlds, alpha= 0.499 produces a > split into a thousand worlds. > > But proponents of MWI like Sean Carroll and Bruno, essentially assume there > are already (infinitely?)
Yes, infinitely, as your own example of 0.499 already suggest. Recently I have found reason that it could even be a *very* large cardinal (I really don’t know, but some axioms in set theory do provide light on the measure problem, It is very technical alas. Bruno > many branches which, prior to the measurement, are identical at the > macroscopic level, but which get projected (split) onto orthogonal subspaces > by a measurement. > > Brent > >> >> 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 everything-list+unsubscr...@googlegroups.com >> <mailto:everything-list+unsubscr...@googlegroups.com>. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/everything-list/CAFxXSLQM-O%3DjP9MOjKuny5%3DWJ2h%3D9fPKqZsaqDibgss0ugRziw%40mail.gmail.com >> >> <https://groups.google.com/d/msgid/everything-list/CAFxXSLQM-O%3DjP9MOjKuny5%3DWJ2h%3D9fPKqZsaqDibgss0ugRziw%40mail.gmail.com?utm_medium=email&utm_source=footer>. > > > -- > 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 > <mailto:everything-list+unsubscr...@googlegroups.com>. > To view this discussion on the web visit > https://groups.google.com/d/msgid/everything-list/fcab7173-3419-1018-6efe-813d2ec5a2d7%40verizon.net > > <https://groups.google.com/d/msgid/everything-list/fcab7173-3419-1018-6efe-813d2ec5a2d7%40verizon.net?utm_medium=email&utm_source=footer>. -- 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 view this discussion on the web visit https://groups.google.com/d/msgid/everything-list/8286A98B-9E0B-4AE6-9503-705765C0A7D6%40ulb.ac.be.
