> On 9 Nov 2019, at 05:06, 'Brent Meeker' via Everything List > <[email protected]> wrote: > > > > On 11/7/2019 2:37 PM, Bruce Kellett wrote: >> On Fri, Nov 8, 2019 at 9:26 AM 'Brent Meeker' via Everything List >> <[email protected] <mailto:[email protected]>> >> wrote: >> On 11/7/2019 1:58 PM, Bruce Kellett wrote: >>> On Fri, Nov 8, 2019 at 8:53 AM 'Brent Meeker' via Everything List >>> <[email protected] >>> <mailto:[email protected]>> wrote: >>> On 11/7/2019 1:40 PM, Bruce Kellett wrote: >>> >>> On Fri, Nov 8, 2019 at 6:35 AM 'Brent Meeker' via Everything List >>> <[email protected] >>> <mailto:[email protected]>> wrote: >>>> On 11/7/2019 12:21 AM, Philip Thrift wrote: >>>>> On Wednesday, November 6, 2019 at 7:27:32 PM UTC-6, stathisp wrote: >>>>> On Thu, 7 Nov 2019 at 11:15, Bruce Kellett <[email protected] <>> wrote: >>>>> On Thu, Nov 7, 2019 at 11:00 AM Stathis Papaioannou <[email protected] >>>>> <>> wrote: >>>>> >>>>> The universe as a whole is determined in every detail, and random choice >>>>> of the observer in measuring a particle is not really a random choice. >>>>> >>>>> If you believe that, you believe in magic sauce. >>>>> >>>>> It is a consequence of Many Worlds that there is no true randomness, but >>>>> only apparent randomness. If Many Worlds is wrong, then this may also be >>>>> wrong. Randomness in choice of measurement is required for the apparent >>>>> nonlocal effect when considering entangled particles. >>>>> -- >>>>> Stathis Papaioannou >>>>> >>>>> >>>>> That's what Many Worlds implies. >>>>> >>>>> The mystery is: Why do (according to the science press in the wake of >>>>> Sean Carroll's book) so many people think Many Worlds is a good >>>>> scientific idea (or the best idea, according to the author). >>>> >>>> Because it treats measurement as just another physical interaction of >>>> quantum systems obeying the same evolution equations as other interactions. >>>> >>>> But you can do that (viz. accept that people, and measuring instruments, >>>> and everything else are basically quantum mechanical) without adopting the >>>> "many worlds" philosophy. >>> >>> ISTM that creates problem for defining a point where one of the >>> probabilities becomes actualized. MWI tries to avoid this by supposing >>> that all probabilities are "actualized" in the sense of becoming orthogonal >>> subspaces. There are some problems with this too, but I see the attraction. >>> >>> You can always find problems with any approach. What I particularly dislike >>> about MW advocates (like Sean Carroll) is that they are dishonest about the >>> number of assumptions they have to make to get the SWE to "fly". >>> Particularly over the preferred basis problem and Born rule. Zurek comes >>> closer, and he effectively dismisses the "other branches" as a convenient >>> fiction. >> >> Yeah, I like Omnes' dictum, "It's a probabilistic theory, so it predicts >> probabilities. What more do you want?" >> >> But it still leaves that gap between the density matrix becoming diagonal >> FAPP and one subspace becoming actual FR (for real), not just FAPP. If you >> take a purely epistemic view the gap is just in your belief changing. But >> if you keep an ontological view the matrix is only diagonal in some >> preferred basis and it's not necessarily even approximately diagonal in some >> other basis. It seems the other bases are an inconvenient fiction. :-) It >> seems to come down to explaining that Zurek's quantum Darwinism necessarily >> picks out the basis in which our brains will form beliefs and they will >> agree on that belief as to what "really happened". >> >> Maybe our brains see it in this way because "that is really what happened". >> It is stochastic, but so what? We are used to updating probabilities on the >> basis of new evidence. Quantum Darwinism is a way of explaining that the >> world itself determines what is real. > > Zurek uses quantum Darwinism and envariance to show there's a preferred basis > and the Born rule is the way to assign probabilities to them once decoherence > has acted. But he doesn't seem to say that one result or another is realized > via the quantum Darwinism. Rather he's satisfied like Omnes' to say "It's a > probabilistic theory so you get predictions of probabilities." Then > observing one, you discard the others as failed predictions. He doesn't > think of the quantum Dawinism as competition between different preferred > basis outcomes to select one as realized. At least that's what I think he > says.
It is more a selection by consciousness than a competition in some precise Darwinian sense I would say, like in the sigma_1 (partial computable) frame. Bruno > > Brent > > -- > 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/c294d23d-a2a3-99c1-e4ef-a82472c58185%40verizon.net > > <https://groups.google.com/d/msgid/everything-list/c294d23d-a2a3-99c1-e4ef-a82472c58185%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 [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/everything-list/76237DFF-67AB-4751-A7BA-4ED853E36923%40ulb.ac.be.
