On Monday, June 11, 2018 at 4:19:34 PM UTC, Bruno Marchal wrote: > > > On 11 Jun 2018, at 12:59, [email protected] <javascript:> wrote: > > > > On Monday, June 11, 2018 at 10:40:13 AM UTC, Bruno Marchal wrote: >> >> >> On 11 Jun 2018, at 07:06, [email protected] wrote: >> >> >> >> On Monday, June 11, 2018 at 2:20:47 AM UTC, [email protected] wrote: >>> >>> >>> >>> On Monday, June 11, 2018 at 2:09:25 AM UTC, Bruce wrote: >>>> >>>> From: <[email protected]> >>>> >>>> On Monday, June 11, 2018 at 1:37:53 AM UTC, Bruce wrote: >>>>> >>>>> From: Bruno Marchal <[email protected] >>>>> Everett prove the contrary, and he convinced me when I read it. I >>>>> found “his proof” used in many books on quantum computing, although with >>>>> different motivation. Thee result of an experiment, obviously depend of >>>>> what you measure, but when you embed the observer in the wave, you get >>>>> that >>>>> what they find is independent of the choice of the base used to describe >>>>> the “observer” and the “observed”. If not, the MW would already be >>>>> refuted. >>>>> >>>>> >>>>> In that case, MW is refuted. Clearly, what the observer finds is >>>>> dependent on the basis in which he is described. Or else experiments >>>>> would >>>>> not have definite results when described in the laboratory from the 1p >>>>> perspective. Even if you take the 'bird' view of the whole multiverse -- >>>>> which is, I agree, independent of the basis in which it is described -- >>>>> the >>>>> view of any observer embedded in the multiverse is totally >>>>> basis-dependent. >>>>> That is, after all, what we mean by 'worlds' -- the view from within, or >>>>> the 1p view. But that view depends on how you describe it: the way in >>>>> which >>>>> you partition the multiverse itself. Only certain very special bases are >>>>> robust against environmental decoherence -- how else do you resolve the >>>>> Schrödinger cat issue? >>>>> >>>>> Bruce >>>>> >>>> >>>> *So you find the resolution in the fact that according to decoherence >>>> theory, the cat is simultaneously alive and dead for only short time? AG* >>>> >>>> >>>> Decoherence has resolved the basis question long before the cyanide has >>>> hit the cat. >>>> >>>> Bruce >>>> >>> >>> *I don't think you've answered the question. Isn't the cat in a >>> superposition of alive and dead before the cyanide hits? Did Schroedinger >>> write an incorrect wf? If so, what is the correct one IYO? AG * >>> >> >> *I surmise your position is that decoherence happens so quickly, that the >> superposition Schroedinger wrote was really a mixed state. If so, I don't >> see this as a solution to the paradox, unless you want to allow the >> existence of a simultaneously alive and dead cat for a very, very short >> time. AG* >> >> >> >> That is why I prefer Bohm’s version of the cat, where the cat alive/dead >> state is corrupted with the up/down state of some particles. It ease the >> mind by showing that the time is not an issue. If you can completely >> isolate the cat from the environment (which is technically impossible), you >> can maintain the cat in the dead + alive superposition state as long as you >> want. If you isolate successfully the entire laboratory including you, >> Then, someone else can resurrect the cat, relatively to himself, despite >> you saw it dead. >> >> The reason why we cannot do this in principle, is that we cannot isolate >> the cat, and if the cat, when the cat is dead+alive, interact with some >> particles in the environment, you can no mare factorize the cat state, >> without tracking that particles. >> >> I don’t think it make sense to confine the superposition in the >> microscopic domain, nor in the short-time domain. If the SWE is correct, >> the superposition never disappear, unless a collapse assumption is made, >> but then it cannot be described by QM. Only by QM + exception rules for the >> observer or the measuring apparatus, but there are no evidences for that. >> >> Bruno >> > > *See my solution to the S Cat on the other thread. Since the cat can > never be isolated, it can never be in a superposition, which generates the > paradox. And since coherence can never occur, no need to apply > decoherence! AG* > > > > I am not sure this make sense (with the SWE). The cat is always isolated, > in some sense. >
*IMO totally wrong. In fact now you're contradicting what you wrote in a recent post. The cat is NEVER ISOLATED, VIRTUALLY BY DEFINITION OF WHAT MACRO MEANS. NEVER ISOLATED IMPLIES NEVER IN A SUPERPOSITION. AG*[snip] -- 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 post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
