On Tuesday, February 2, 2021 at 3:51:00 AM UTC-7 Bruno Marchal wrote:
> On 30 Jan 2021, at 05:06, Alan Grayson <[email protected]> wrote: > > > > On Friday, January 29, 2021 at 8:19:47 PM UTC-7 Alan Grayson wrote: > >> On Friday, January 29, 2021 at 3:00:17 PM UTC-7 Brent wrote: >> >>> >>> >>> On 1/29/2021 5:52 AM, Bruno Marchal wrote: >>> >>> >>> If you induce decoherence by measuring at the slits, then the >>> interference pattern disappears -- you have certainly created a separate >>> "world" for each path, but these can no longer interfere. That is part of >>> the definition of the "worlds" that are created by irreversible decoherence. >>> >>> >>> >>> No problem. >>> >>> >>> >>> So the concept of "world" is, indeed, well-defined in physics. >>> >>> >>> >>> By giving a magic role to the observer, or its consciousness, or of >>> measurement. The observer can no more be a machine in that picture. >>> >>> >>> There's no magic or observer invoked. That's the function of >>> decoherence, which operates independent of observers or deliberate >>> measurement. >>> >>> >>> >>> >>> >>> >>> It might not be defined in logic or metaphysics, but this is of no >>> concern to the working physicist -- we know perfectly well what we mean by >>> "a world”. >>> >>> >>> FAPP. OK. >>> The goal here is to try to understand what happens. >>> >>> >>> >>> And we can readily tell when someone is talking nonsense by claiming >>> that "worlds interfere statistically without interacting”. >>> >>> >>> ? (That is rather standard, and pretty obvious, I would say). >>> >>> >>> Really? I've never heard of it and it seems pretty obviously nonsense >>> to me. >>> >> >> *I made a similar comment when this word salad of nonsense was first >> posted by Bruno. It's Trump Physics in spades, full of sound and fury but >> signifying nothing; that is, no contact with real physics. Yet you think I >> go too far. Baffling. AG * >> > > *Another weirdness is the MWI claim by the usual suspects that QM leaves > "measurement" and "observer" undefined. * > > > Because the collapse is itself not explain, and this introduce a dualism > in the ontology. Bohr was aware of this. > *Why is "dualism" a dirty word? AG * > > With Everett, the observer is well defined, although Everett does not do > it mathematically. It invokes an automata, but in fact his argument has to > be generalised on arithmetic if that automata is Turing universal, like us. > Everett confirms the “many-histories” inherent in the fact that all > computations are realised in the standard model of arithmetic (which can be > defined by the intersection of all models of arithmetic). > > Bruno > > *I explained this earlier, but alas, they prefer their ridiculous claims. > E.g., in the double slit experiment, a "measurement" occurs when a particle > hits the screen. The "observer" is anyone or anything that records the > result. Nothing particularly deep here, but the usual suspects find these > definitions woefully wanting. Trump Physics in play. AG* > > >>> 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]. > > To view this discussion on the web visit > https://groups.google.com/d/msgid/everything-list/93f22ad5-d51d-41cc-bd6a-d8cde0ed4d5cn%40googlegroups.com > > <https://groups.google.com/d/msgid/everything-list/93f22ad5-d51d-41cc-bd6a-d8cde0ed4d5cn%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/b709f21e-cdc5-439f-9e80-cdff4a560d34n%40googlegroups.com.
