> On 23 Feb 2020, at 23:25, Bruce Kellett <[email protected]> wrote: > > On Mon, Feb 24, 2020 at 12:00 AM Bruno Marchal <[email protected] > <mailto:[email protected]>> wrote: > On 22 Feb 2020, at 05:37, Bruce Kellett <[email protected] > <mailto:[email protected]>> wrote: >> >> I am not sure that I completely understand what Zurek has done here. The >> problem of carrying the initial amplitdues through a sequence of repeated >> trials is opaque to me. > > It seems to me that this is a direct consequence of the linearity of the > tensor product. > > I interpret for example the 1/sqrt(2) in a superposition as describing an > infinity of accessible histories, where I can access some particle state (and > eigenvalue) with a probability one half. If I make a measurement, that > “1/sqrt(2)” is inherited by the state describing me + that particle. > > I me> (1/sqrt(2) a + 1/sqrt(2) b) = 1/sqrt(2) Ime>Ia> + 1/sqrt(2) Ime>Ib>. > The weigth of a has passed on me, by linearity/unitarity. > > Sure, you can write 1/sqrt(2) in front of each term. But the relative state > in each case is the |me>, and that does not depend on the leading coefficient.
Why? With such an interpretation, QM would not work. The relative coefficients gives the superposition state that you are in. You could as well say that there is no probabilities in the coin tossing, because each “history” is independent of all the counterfactuals, but then there is no more any probabilities at all, anywhere. > When you, in a single trial, see |up> (i.e., the state is |me, who sees up>), > how does that depend on the 1/sqrt(2)? Because that 1/sqrt(2) told me in advance that once I consider the wave of me + the particles, belong to that superposition. It explains the probability that I observe, including if I rotate my experimental device, by trotting differently the mixture from the pure state. All use of probabilities are based on some theories. The only problem for Everett is that once he uses mechanism, he has to extract the wave itself from all computations realised in arithmetic (i.e. *all* computations, with their complex redundancies, as we accept the Church-Turing thesis). > From the first person perspective, remember -- do not mix in your 3p opinions. That is the whole problem: finding a 3p sharable description of the big picture which explains the 1p local picture in a way which is coherent with all the observers experiences and descriptions. The mind-body problem is the 1p/3p relation problem. Thanks to QM weirdness, physicist are brought to it. Bruno > > Bruce > > Bruno > > > > > > >> Zurek seems to rely on the number of envariant environmental states somehow. >> I will have to look into this further: it all needs a little untangling. I >> can't quite see how the weights carry through repeated measurements -- the >> state is surely a new state in each branched world. >> >> 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 view this discussion on the web visit >> https://groups.google.com/d/msgid/everything-list/CAFxXSLQ3xDwGaSg8wUEweT%3Dh%2BncYeD0MJE8jyTmn6CgPN8jhRQ%40mail.gmail.com >> >> <https://groups.google.com/d/msgid/everything-list/CAFxXSLQ3xDwGaSg8wUEweT%3Dh%2BncYeD0MJE8jyTmn6CgPN8jhRQ%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 [email protected] > <mailto:[email protected]>. > To view this discussion on the web visit > https://groups.google.com/d/msgid/everything-list/7FCD6C6F-5881-4034-98A0-C1AF24207D24%40ulb.ac.be > > <https://groups.google.com/d/msgid/everything-list/7FCD6C6F-5881-4034-98A0-C1AF24207D24%40ulb.ac.be?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] > <mailto:[email protected]>. > To view this discussion on the web visit > https://groups.google.com/d/msgid/everything-list/CAFxXSLQaBuqAyu7Z5c-vbe-yqR4LRnEOZJwbnZ4-sHd869TMzQ%40mail.gmail.com > > <https://groups.google.com/d/msgid/everything-list/CAFxXSLQaBuqAyu7Z5c-vbe-yqR4LRnEOZJwbnZ4-sHd869TMzQ%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 [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/everything-list/7F3E1A86-12B9-4AC8-90B3-423080F07ED6%40ulb.ac.be.
