On Friday, April 27, 2018 at 5:38:38 AM UTC, agrays...@gmail.com wrote: > > > > On Friday, April 27, 2018 at 5:10:46 AM UTC, Brent wrote: >> >> >> >> On 4/26/2018 9:24 PM, agrays...@gmail.com wrote: >> >> >> >> On Friday, April 27, 2018 at 1:43:30 AM UTC, Brent wrote: >>> >>> >>> >>> On 4/26/2018 6:21 PM, agrays...@gmail.com wrote: >>> >>> >>> >>> On Friday, April 27, 2018 at 1:10:25 AM UTC, Brent wrote: >>>> >>>> >>>> >>>> On 4/26/2018 4:14 PM, agrays...@gmail.com wrote: >>>> >>>> >>>> >>>> On Thursday, April 26, 2018 at 10:25:29 PM UTC, Brent wrote: >>>>> >>>>> >>>>> >>>>> On 4/26/2018 2:33 PM, agrays...@gmail.com wrote: >>>>> >>>>> >>>>> >>>>> On Thursday, April 26, 2018 at 9:09:48 PM UTC, Brent wrote: >>>>>> >>>>>> >>>>>> >>>>>> On 4/26/2018 7:23 AM, agrays...@gmail.com wrote: >>>>>> >>>>>> >>>>>> >>>>>> On Thursday, April 26, 2018 at 4:12:41 AM UTC, Brent wrote: >>>>>>> >>>>>>> >>>>>>> >>>>>>> On 4/25/2018 7:44 PM, agrays...@gmail.com wrote: >>>>>>> >>>>>>> >>>>>>> >>>>>>> On Thursday, April 26, 2018 at 2:17:31 AM UTC, Brent wrote: >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> On 4/25/2018 6:39 PM, agrays...@gmail.com wrote: >>>>>>>> >>>>>>>> >>>>>>>> *On its face it's absurd to think the SoL is invariant for all >>>>>>>> observers regardless of the relative motion of source and recipient, >>>>>>>> but it >>>>>>>> has testable consequences. The MWI has no testable consequences, so it >>>>>>>> makes no sense to omit this key difference in your historical >>>>>>>> comparisons >>>>>>>> with other apparent absurdities in physics. Moreover when you factor >>>>>>>> into >>>>>>>> consideration that non locality persists in the many worlds postulated >>>>>>>> -- >>>>>>>> assuming you accept Bruce's analysis -- what exactly has been gained >>>>>>>> by >>>>>>>> asserting the MWI? Nothing as far as I can tell. And the loss is >>>>>>>> significant as any false path would be. AG* >>>>>>>> >>>>>>>> >>>>>>>> It's one possible answer to the question of where the Heisenberg >>>>>>>> cut is located (the other is QBism). It led to the theory of >>>>>>>> decoherence >>>>>>>> and Zurek's theory of quantum Darwinism which may explain Born's rule. >>>>>>>> >>>>>>>> Brent >>>>>>>> >>>>>>> >>>>>>> * I've always found the Heisenberg Cut to be a nebulous concept, a >>>>>>> kind of hypothetical demarcation between the quantum and classical >>>>>>> worlds. * >>>>>>> >>>>>>> >>>>>>> That's the problem with it; it doesn't have an objective physical >>>>>>> definition. Bohr regarded it as a choice in analyzing an experiment; >>>>>>> you >>>>>>> put it where ever was convenient. >>>>>>> >>>>>>> *What kind of boundary are we talking about, and how could the MWI >>>>>>> shed any light on it, whatever it is? AG * >>>>>>> >>>>>>> >>>>>>> In MWI there is no Heisenberg cut; instead there's a splitting of >>>>>>> worlds which has some objective location in terms of decoherence. >>>>>>> >>>>>>> Brent >>>>>>> >>>>>> >>>>>> The Heisenberg Cut is too vague and ill-defined to shed light on >>>>>> anything, and to say the MWI is helpful is adding another layer of >>>>>> confusion. AG >>>>>> >>>>>> >>>>>> Decoherence is a specific well-defined physical process and it >>>>>> describes the splitting of worlds. There is still some question whether >>>>>> it >>>>>> entails the Born rule, but at worst the Born rule remains as a separate >>>>>> axiom. >>>>>> >>>>>> Brent >>>>>> >>>>> >>>>> Let's say an electron goes through an SG device. IIUC, its spin state >>>>> becomes entangled with the spin wf's of the device. How do you infer >>>>> splitting of worlds from this? AG >>>>> >>>>> >>>>> I don't. Why should I? >>>>> >>>>> Brent >>>>> >>>> >>>> I could swear that you wrote above that decoherence describes the >>>> splitting of worlds, so I gave you an example of decoherence >>>> >>>> >>>> You didn't give an example of decoherence. Where's the decoherence in >>>> an electron flying through a divergent magnetic field? >>>> >>>> Brent >>>> >>> >>> That's what I figured you would write and maybe you're correct. I >>> thought decoherence means that the wf of the system being measured, gets >>> entangled with the wf's of the environment, in this case the SG device. Why >>> is this not decoherence, and if it isn't, what is? TIA, AG >>> >>> >>> Decoherence happens when the particle is detected in one path or the >>> other, not when going thru the SG. It's a classic experiment to show that >>> particle wf can be coherently recombined after going through SGs. So if >>> you set up a detector on one leg of the SG then the world splits when there >>> is a detection vs no detection. >>> >>> Brent >>> >> >> I am not considering a singlet state; just an electron passing through a >> SG device and being measured, spin up or down. Are you saying no >> decoherence in this case? >> >> >> No. I just saying when you posed the problem you didn't say anything >> about detection. You just said an electron went through an SG apparatus. >> >> From what I gather from descriptions of decoherence, it occurs when a >> measurement occurs, and the particle's wf gets entangled with the >> measurement device. This is a detection, and I think you're saying the >> world splits. If so, why would it? If there's no detection for whatever >> reason, what are we to conclude? I would guess, nothing. AG >> >> >> No. The world still splits because no-detection means the particle took >> the other path where there was no detector, at least that's the MWI >> theory. >> > > *Can't no detection just mean an inefficient measuring device? AG* > > >> This is confirmed by the buckyball Young's slit experiment. The >> interference pattern disappeared even though the IR photons weren't >> measured. >> >> You've been around these lists for years. Haven't you read these >> experiments? >> >> Brent >> > > > *Just SG, not Buckyball. Not sure what Buckyball proves. You have an > interference pattern when it goes through slit, and no IR photons detected. > What does one thing have to do with another? Sorry; this is very confusing. > AG* >
I meant to write; the pattern disappears (and no IR photons detected). Don't know how to interpret the results you describe. AG > > *Earlier, this particular discussion began with your comments about the > Heisenberg Cut and you claimed it said something about splitting of worlds. > "Decoherence is a specific well-defined physical process and it describes > the splitting of worlds." If you don't believe in the MWI, how can you > claim decoherence is well defined and supports splitting of worlds? AG* > >> -- 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 post to this group, send email to everything-list@googlegroups.com. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
