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Answer for schrodinger cat paradox

  1. Dec 27, 2004 #1
    Recently I have read "Beyond The Quantum Paradox" by Lazar Mayants. The author claimed that Schrodinger Cat Paradox can be solved by the following way:
    "Since the reasoning of conventional quantum mechanic employs probability, it must concern an abstract cat, whereas any cat experiment, even an imaginary one, should be related to a concrete cat. But every concrete cat during the experiment has only one of the two possible values, 'alive' and 'dead', of the property 'state of being', whereas an abstract cat does not exist in reality at all. Therefore, the question concerning the 'state of being' of an abstract 'Schrodinger's Cat', as stated above, is senseless."

    What do you think?
  2. jcsd
  3. Dec 27, 2004 #2
    Re: Sc

    I think you might of missed the entire point of the Schrodingers Cat example.

    It was a thought experiment designed for people to get to grips with the idea of particle wave duality and quantum probability, the cat is completely irrelevant, you could just as easilly substitute radioactive helium for cat and radioactive helium for the poison, smashing the two together to form entangled electrons.

    Whatever terminology you use it matters not just the idea behind it; cat dog mongoose tachyon dark energy whatever; maybe the author was being ironic either that or he too missed the point:rolleyes:

    later :smile:
    Last edited by a moderator: Dec 27, 2004
  4. Dec 27, 2004 #3
    In an ideal von Neumann experiment, you can have a pre-measurement state of particle and a detector, then measure the particle and get a post-measurement state for the particle and the detector... but you can later recreate the pre-measurement state of the particle and the detector.

    This means, in principle, Schrodinger's cat can go from an alive state to a dead state and then back to the alive state again! :bugeye:

    Using that author mentioned in the first post's terminology, it's not easy to see how a result can be called "concrete" when a cat can be turned from a concrete live cat to a concrete dead cat back into a concrete live cat. What's concrete about a result that can be reversed? :smile:

    In reality, of course, you can't do that with something the size of a cat but you could do it with a couple of particles. Decoherence is the reason why it can't be done with something as large as a cat or anything much larger than the atomic scale.

    The real point of Schrodinder's cat paradox is a question of why we end up with a permanent record of an event from only the possibilities of events and even reversible events. The answer to that is the theory decoherence proposed a few decades ago and experimentally confirmed within the last decade.

    The countless particles interacting with the cat cause the decoherence which makes the cat's dead/alive state become a permanent state of being either dead or alive. And it all happens in less than a billionth of a second even for tiny and isolated objects, never mind something the size of a cat.

    So the cat's fate remains the cat's fate and can be called "concrete". The superposition of alive/dead states, however, is not really "abstract" but is a genuine physical state that is easily destroyed by particle interactions.
    Last edited: Dec 27, 2004
  5. Dec 27, 2004 #4


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    If you cannot see it, feel it, taste it, hear it, perceive it, by what stretch of logic do you say it exists? if you cannot get to the Cat, baseball, rose, or what ever, how can you say anything about the state of the cat? You don't know until you look. Period.
    Physics is, after all, highly empirical.


    Schrodinger's Cat is about probability, not only QM, but stochastic processes, Kalman Filtering, Time Series Forecasts, and so on.

    Seems to me that ascribing multiple realities to a cat, or electron, or,..... makes physics far more complex than necessary, makes physics look like it's reaching for mysticism and serves no useful purpose.

    Reilly Atkinson
  6. Dec 27, 2004 #5


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    Pardon my excrusion...

    Seems to me that any "concrete" cat must be dead. All of the live ones are made of flesh.
  7. Jan 3, 2005 #6
    Reilly said:

    "makes physics look like it's reaching for mysticism and serves no useful purpose."

    I'm new here, but is it "reaching for mysticism" or is it looking for a new paradigm and the mystics happen to have the trade mark on the view that works?

  8. Jan 4, 2005 #7


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    Sim -- Welcome. What's this view that works that you ascribe to mystics?
    Reilly Atkinson
  9. Jan 4, 2005 #8

    Thanks for the welcome Reilly

    I can't say I subscribe to a view, but being relatively knew to QM I have no prior paradigm to overcome. What I see, however, is a general inability on the part of many to relate the QM world to the macro world.

    Einstein hated the uncertainty, the probability/indeterminism and the fact that we, the observers, seem to have such an influence on what we call reality. But he failed to prove this wrong. I'm not subscribing to F. Capra's view, but it does convey what the perenial philosophies have been saying. While they (the mystics) have no answers, that I am aware of, their view fits what we know: connectivity, we have an influence on our reality if not control of it, EVERYTHING is energy, and we are part of it, just to scratch the surface.

    Like the period in the early 1920's when viewing evidence by new to physicists without the Newtonian view was advantagious for theoritical physics, could it be that a knew, liberal, controversial approach to the evidence today could result it another burst of understanding?

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