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Theory that most physicists believe that the decision

  1. Dec 11, 2009 #1
    what is the theory that most physicists
    believe that the decisions that we didn't make
    we live them on another life? something like that

    please help
    Last edited: Dec 11, 2009
  2. jcsd
  3. Dec 11, 2009 #2
    Re: physicists

    Sounds like "Sum over histories" to me.
  4. Dec 11, 2009 #3


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    Re: physicists

    Our entire universe rests on a turtle.

    Caution, there may be irony in this post.
  5. Dec 11, 2009 #4
    Re: physicists

    Uh, I think you might be talking about the "many worlds theory." But this isn't really a legitimate physics theory (in science a theory is a model that's been verified by numerous experiments). Honestly I never even learned about it in physics classes, I only know about it from popular literature, sci-fi, etc.
  6. Dec 12, 2009 #5
    Re: physicists

    The many-worlds theory is supposed to be consistent with other, more accepted quantum theories, but may have the advantage of continuity of reality, e.g., no wavefunction collapse, however at the expense of accumulating extreme intricacy.

    Every measurement you make would be a choice between two universes, say one where an observed electron has spin up, and the other spin down. The number (n) of universes increases geometrically with the number of measurements (m), roughly:

  7. Dec 12, 2009 #6


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    Re: physicists

    Many worlds is more of an interpretation of quantum mechanics than a theory itself. I believe it's the second most popular interpretation next to Copenhagen.
  8. Dec 12, 2009 #7
    Re: physicists

    To me it sounds more like a psychic on karma than a physicist on the many-worlds interpretation.
  9. Dec 12, 2009 #8
    Re: physicists

    Something just occured to me. You'd only get two universes when the Hilbert space is finite-dimensional. When your wavefunction exists in function space and can be decomposed into an infinite number of Fourier terms, you would literally get an infinite number of universes from making the measurement.
  10. Dec 12, 2009 #9
    Re: physicists

    [I should have written "exponentially" rather than "geometrically" in my previous post.]

    Isn't an initial discrete measurement (e.g., that represented by a Dirac delta function) Fourier-decomposable into an infinity of Hilbert spatial dimensions, but only represents a finitude of "phase space" universal histories.

    I'm really not sure what space Many-Worlds take place in.
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