On Monday, June 11, 2018 at 10:40:13 AM UTC, Bruno Marchal wrote: > > > On 11 Jun 2018, at 07:06, [email protected] <javascript:> 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* -- 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.
