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Quantum mechanics and causality/determinism.

  1. Aug 17, 2011 #1
    Would this be accurate:

    We can say that our universe is not deterministic because we can't identify, with arbitrary precision, what will happen with each particle on the quantum level (due to HUP, entanglement, etc). However, they are all part of a statistical framework/wavefunction which we can describe deterministically.

    In other words, it'd be like if we couldn't predict the roll of a die (random), but could describe it statistically (deterministically). Would this be accurate?

    Does this mean that causality doesn't exist on the macro level (technically-speaking), but rather just a large probability where things causally turn out due to statistical projections at near-100% levels?
    Last edited: Aug 17, 2011
  2. jcsd
  3. Aug 17, 2011 #2
    What you are saying is more or less in accordance with what a lot of people view QM as.

    However noone really knows what QM is really telling us about nature, there are several fully deterministic models of QM. (Bohm, MWI, other hidden variables, t Hooft etc.)
    So QM is really agnostic about this issue.
    Just the fact that we indeed can construct 100% deterministic interpretations is enough to convince me that reality is 100% deterministic, we just don't know all the details yet.
  4. Aug 17, 2011 #3
    Flip a coin, the more times you flip it, the closer you will get to 50/50. Hope this helps.
  5. Aug 17, 2011 #4


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    Just the fact that we indeed may imagine green elephants with two heads is not enough to convince me that such monsters are even a part of reality.

    Don't forget about the price you must pay for those deterministic interpretations. Is indeterminism more difficult to accept than idea that each humble event depends on everything else in the Universe? Or exponentially (with pretty big exponent) growing number of parallel Unverses is easier to accept than indeterminism?
  6. Aug 17, 2011 #5
    Would we say the same thing about evolution?

    We say evolution is very much non-random, but mutation is random. Is it still technically random, or just so chaotic that we can't keep track of the variables, but if we could, it wouldn't be "random"?
  7. Aug 18, 2011 #6
    When we think of real numbers or complex numbers nothing is too small to get a number.
    If we think of a quantized world needs something - probably - be too small to make any difference.
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