On Thu, Mar 5, 2020 at 12:41 PM 'Brent Meeker' via Everything List < everything-list@googlegroups.com> wrote:
> On 3/4/2020 4:48 PM, Bruce Kellett wrote: > > On Thu, Mar 5, 2020 at 10:50 AM 'Brent Meeker' via Everything List < > everything-list@googlegroups.com> wrote: > >> >> For example, if you take Zurek's quantum Darwinism to provide an >> objective pointer basis then you can say, in this basis, off-diagonal terms >> in the reduced density matrix that are so small they will never be observed >> can be set to zero and then the diagonal terms are just the probability of >> the (one) world that will be actual. >> > > That is still a probabilistic assertion. And no derivation of > probabilities for cases in which all outcomes occur is going to be > successful. > > > That's not what I'm arguing. I arguing that there is a way to make sense > of a and b as "weights" whose square magnitudes give probabilities. The > significance of Zurek's quantum Darwinism is that it provides and objective > pointer basis. > That is not how Zurek derives a preferred pointer basis. Originally, his derivation relied on the concept of einselectin -- robustness against environmental decoherence. But he later modified this to eliminate the implied dependence of einselection on the Born rule. His later derivation of a pointer basis relied on the side that a measurement must leave a distinct impression on the environment. Quantum Darwinism then comes into play from the fact that the robustness of the pointer basis means that multiple impression of the result can be imprinted on the environment without changing the pointer reading, leading to the emergence of an intersubjectively realized classical world. > Without that one can always says, no matter how small the off diagonal > terms are, there's another equally valid basis in which they aren't small. > > > The arguments for probability assignments given by Zurek (and Carroll and > Wallace, among others) all rely, at some point, on the "intuition" that > equal amplitudes equate to equal probabilities. It is that assumption that > I have shown to be false. > > > If you make it an axiom it ain't false. > But an axiom is useless if it does not give results in agreement with experiment. And the assumption of equal probabilities from equal amplitudes is disconfirmed by the majority of observers when there are repeated trials with binary outcomes when both outcomes occur. 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. To view this discussion on the web visit https://groups.google.com/d/msgid/everything-list/CAFxXSLQdmsZ8zPqCY5dpYQeQGwrbEqHFsAqOR-Rcj80U6GTt0w%40mail.gmail.com.
