On Fri, Nov 8, 2019 at 1:42 PM Alan Grayson <[email protected]> wrote:
> On Thursday, November 7, 2019 at 6:27:22 PM UTC-7, Bruce wrote: >> >> On Fri, Nov 8, 2019 at 12:01 PM Alan Grayson <[email protected]> wrote: >> >>> On Thursday, November 7, 2019 at 5:25:56 PM UTC-7, Brent wrote: >>>> >>>> On 11/7/2019 4:13 PM, Alan Grayson wrote: >>>> >>>> They've sent 2000-atom sized molecules through double slits. >>>>> >>>>> What about sending cats? >>>>> >>>>> >>>>> You will loss the ability to get the interference, because it is >>>>> hugely more complex to isolate a cat from the environment, so its alive or >>>>> dead state will be pass on you unavoidably very quickly. See my >>>>> explanation to Grayson why any (unknown) interaction of an object in a >>>>> superposition state makes it logically impossible to remain in a >>>>> superposition relatively to you. It uses only very elementary algebra. The >>>>> quantum effect, to be exploited, require perfect isolation, which is >>>>> impossible for most macroscopic object. But some “macro-superposition” >>>>> have >>>>> been obtained with superconducting device. In fact, superconductor is a >>>>> quantum macroscopic effect. >>>>> >>>>> >>>>> Aside from the isolation problems the de Broglie wavelength of a cat >>>>> is extremely small so to get an interference pattern the slit and slit >>>>> spacing must be correspondingly small. The C60 experiment was only made >>>>> possible by the development of the Tablot-Lau interferometer. >>>>> >>>>> Brent >>>>> >>>> >>>> I've made this point before; the decoherence time for a cat is very >>>> very short, but how does this effect the point Schroedinger wanted to make, >>>> since the cat is in that paradoxical superposition for some short but >>>> finite duration? AG >>>> >>>> >>>> There is no paradox. It's just some hang up you have that a cat can't >>>> be dead and alive at the same time. It's as though your physics was stuck >>>> in the time of Aristotle and words were magic so that "Alive implies >>>> not-dead." was a law of physics instead of an axiom of logic. >>>> >>>> In fact a moments thought will tell you that quite aside from quantum >>>> mechanics there would be no way to identify the moment of death of the cat >>>> to less than a several seconds. It would be simply meaningless to say the >>>> cat was alive at 0913:20 and dead at 0913:21. >>>> >>>> Brent >>>> >>> >>> You can imagine a different experiment, without cats, with the same >>> paradoxical result. The point of Schroedinger's thought experiment was to >>> demonstate tHE title of this thread; that there's something wrong with the >>> prevailing interpretation of superposition. In your view I am hung up with >>> Aristotle? In my view, you're seduced by some quantum nonsense. AG >>> >> >> We have moved on somewhat in the 80-plus years since Schrodinger's >> thought experiment. The "prevailing view" is now different from his, so >> what he thought he had demonstrated is no longer particularly relevant. >> >> Bruce >> > > Fair enough. So what is the "prevailing view" now? Isn't it (in the > context of Brent's last post) that a radioactive atom can be simultaneously > decayed and undecayed? How is this different from the days of Schroedinger? > AG > Decoherence is rapid. Schrodinger did not know about this. But the SWE predicts momentary superpositions -- at least until the environment enforces the preferred basis. 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]. To view this discussion on the web visit https://groups.google.com/d/msgid/everything-list/CAFxXSLSOA3B2_hY4deFSGNx%2Bh4aHFaXE0mNtN4hq_4T89v%2BYdA%40mail.gmail.com.
