> On 3 Jan 2021, at 03:43, Alan Grayson <[email protected]> wrote: > > > > On Saturday, January 2, 2021 at 2:17:12 AM UTC-7 [email protected] wrote: > On Fri, Jan 1, 2021 at 5:35 PM 'Brent Meeker' via Everything List > <[email protected] > <applewebdata://1EB9B6F7-F829-465D-9D14-1A00008462F9>> wrote: > > >> Assuming that Many Worlds is true and the multiverse is completely > >> determined by Schrodinger's equation and there are therefore an > >> astronomically large number (perhaps an infinite number) of Bruce Kelletts > >> with microscopic or submicroscopic differences between them, > >> and those Bruce Kelletts were observing a stream of photons polarized at > >> angle X hit a polarizing filter set to angle X+Y; would any one of those > >> Bruce Kelletts be able to predict with certainty that Bruce Kellett would > >> or would not observe the photon pass through that filter? No. Would Bruce > >> Kellett have to resort to probability? Yes. How would Bruce Kellett > >> calculate the probability? If Bruce Kellett wanted to avoid logical self > >> contradictions there is only one method Bruce Kellett could use, the Born > >> Rule. > > > I don't think that's quite true. Suppose for example BK decided to predict > > that the polarization with the highest value of |psi|^2 is the one that > > would pass thru. He wouldn't run into any logical contradiction because > > he's not interpreting it as probability, > > If the BKs are Interpreting that as a certainty and not a probability then > the BKs wouldn't run into a logical contradiction but they would run into an > empirical one because that wouldn't match experimental observation. It's > entirely possible that a BK's prediction would fail and that the high |psi|^2 > photon would NOT make it through (unless the value happened to be exactly 1), > and even if the prediction turned out to be correct scientific experiments > must be repeatable and when the BKs conduct it over and over again all the > BKs will soon find out that the predictions tend to be correct |psi|^2 of the > time. > > > he wouldn't run into an empirical contradiction unless he assumed the > actual process was producing a probability distribution and so he needed to > predict a distribution and not just a value. > > But the BKs didn't assume it was a probability distribution, they discovered > it was. If the BKs assumed the |psi|^2 value was just a number and not a > probability and had no physical significance then the BKs would soon discover > that the assumption was wrong > > > Once you know that you need a probability distribution from the wave > > function...then Born's rule is the only choice. > > Yes. > > > But it's the step from the wave-function and "everything happens" to a > > probability distribution where MWI leaves a gap. > > I don't see the gap. If Many Worlds was true then what would the Brent > Meekers interpret |psi|^2 to mean? If it's just a number and means nothing > then solving Schrodinger's equation would be a waste of time because that > equation would also mean nothing, it should be ignored; but then we wouldn't > have transistors or lasers or about 6.02*10^23 other things in modern life. > > The gap Brent refers to has nothing to do with Schrodinger's equation, as I > previously explained. Every trial in an experiment can be interpreted as a > separate horse race, creating its own set of worlds where each possible > occurrence is allegedly measured. But on subsequent trials, the MWI gives no > guarantee that the same set of worlds is created. IOW, without another > postulate appended to the MWI, each world is associated with exactly ONE > measurement. No ensembles in these worlds; hence, the necessary condition for > a probability doesn't exist. AG.
The born rule must be applied, and it concerns the relative accessible histories. It is better to avoid the term “world” which is hard to define. Bruno > > John K Clark See my new list at Extropolis > <https://groups.google.com/g/extropolis> > > > -- > 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 view this discussion on the web visit > https://groups.google.com/d/msgid/everything-list/fa4b28ff-6606-4e06-9c22-d758906538d9n%40googlegroups.com > > <https://groups.google.com/d/msgid/everything-list/fa4b28ff-6606-4e06-9c22-d758906538d9n%40googlegroups.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 [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/everything-list/79146F19-915D-4CCE-A5D8-922F8C47AD09%40ulb.ac.be.
