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Reinterpretation of classical physics in operator/amplitude/e.v.?

  1. Mar 28, 2013 #1


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    Presumably it's easy to re-formulate non-quantum (i.e., classical) physics entirely in operator -> observable form (perhaps even to the point of using bra/key and amplitude^2 notation, etc -- although since macroscopic objects are supposed to be in a single location, everything would end up being delta functions, or something like that). Can someone point me to someplace that summarizes how this is done? (Maybe this should be a question for classical physics topic, but they might not know what I'm talking about.)
  2. jcsd
  3. Mar 28, 2013 #2
    I don't think it's easy, but if I understand your question right, it has been done:

    Koopman-von Neumann mechanics

    As Koopman and von Neumann demonstrated, a Hilbert space of complex, square integrable wavefunctions can be defined in which classical mechanics can be formulated as an operatorial theory similar to quantum mechanics.

    This might also be relevant: I saw a talk from some people who worked on smooth transitions between KvN theory and orthodox quantum mechanics. They called it Operational Dynamic Modeling.
  4. Mar 29, 2013 #3


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    Awesome! That *exactly* what I was thinking of. (I'd say something about great minds thinking alike, but it seems way too pretentious to compare my mind to von Neumann's! :-)

    Anyway, thanks!
  5. Mar 29, 2013 #4
    I do that all the time. Whoa, cool, I've just made a big discovery! followed by Oh ****, [famous physicist or mathematician] already figured that out several decades ago and I just didn't know about it.

    Von Neumann's name comes up a lot, though I think the all-time champion of I-already-thought-of-that has to be Gauss.
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