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Accuracy of this statement

  1. Aug 24, 2005 #1


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    What is the accuracy of this statement?

    "Something strange is going on in physics, something so strange, in fact, that some people who've bothered ot think about the strangenoess now declare that physics is looking more and more like Eastern mysticism. This weirdness is taking place in the branch of physics known as quantum mechanics, which studies subatomic particles, the tiny bits that make up everything in the universe. The notorious weirdness is this. In the quantum realm, particles don't acquire some of their characteristics until they're observed by someone. They seem not to exist in a definite form until scientists measure them. This spooky fact didn't sit well with Einstein, bu it has been confirmd repeatedly in rigorous tests. It has caused some people to speculate that reality is subjective, that we as observers create hte universe ourselves - that the universe is a product of our imagination. This quantum freakiness has prompted some people, even a physicist or two, seriously to ask, "Is a tree really there when no one's looking?" - Theodore Schick, Jr, Lewis Vaughn "How to think about Weird Things"
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  3. Aug 24, 2005 #2
    In quantum mechanics a measurement is a strange thing indeed. But this quotation seems to imply that it is the intervention of a human that causes particles to take a stand about their characteristics. This is not the case, it is the contact between a particle and a macroscopic object that forces definite characteristics upon the particle or other microscopic object.

    But it is (by most physicists believed to be) true that particles don't have e.g. a definte position or velocity until they are 'observed'/'measured'.
  4. Aug 24, 2005 #3


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    Accurate, but misleading if you think this is a secret or something new. This has been noticed, contemplated and debated for a long time by the greatest minds in physics, at least since 1930.

    I think the EPR-Bell-Aspect series of papers goes a long way towards showing that the observer has an important relationship to the reality being observed.
  5. Aug 24, 2005 #4


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    I'm just interested in how accurate it is. The author makes it seem like something 'spooky' and on par with ESP or aliens.
  6. Aug 24, 2005 #5
    The philosophy is pretty spooky, but unlike ESP or aliens this is philosophy being derived from highly functional mathematical physics. It is entirely possible to use quantum mechanics without ever caring how important the observer is to the system. Formulations of QM have also been produced that largely remove this measurement issue, though I think some would argue they introduce new problems of different natures.

    So maybe its spooky, but nothing like ESP or aliens.
  7. Aug 24, 2005 #6
    There is nothing to suggest that humans have a special role.
  8. Aug 24, 2005 #7
    Its totally inaccurate garbage.

    Wrong. It is true that that measuring a particles' momentum leaves it in a state of definite momentum, but that doesn't mean it aquired the characteristic of momentum at the time of measurement.
  9. Aug 24, 2005 #8
    The passage you presented is an accurate representation of what
    some people say -- but what they're saying isn't an accurate
    representation of the meaning of quantum theory and experimental

    Keep in mind that 'particle' in quantum physics doesn't mean what
    'particle' does in ordinary language. In quantum physics, 'particles'
    refer to recorded results of experiments (data), the sets of operations
    (the things experimenters do to the hardware they're using) that
    are associated with the data, and the numerical representations
    of this (so that physicists can communicate unambiguously).

    But what, exactly, does all of the above refer to in some
    submicroscopic realm, at the level of the physical stuff that the
    instruments are filtering/detecting? Are there particles (in the
    ordinary sense), or waves in particulate media, or waves in
    non-particulate media, or what? Nobody knows for sure.

    Ideas of spooky action-at-a-distance, connections to Eastern
    mysticism, or that things which we *can* sense (like data, and
    trees, and hardware, and theories, and tables and chairs) somehow
    don't exist when we aren't sensing them -- all of these ideas come
    from the desire to have an accurate picture (in the ordinary sense of
    the word picture) of an unseen submicroscopic realm, and the
    fact that we don't have such a picture.

    Attempts to satisfy this desire have so far produced some
    'pictures' of the unseen physical world that are impossible
    (ie., freaky or weird) wrt the logic of the world of our
    sensory experience.
  10. Aug 24, 2005 #9

    George Jones

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    I'm curious: What's your take on the Kochen-Specker theorem?

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