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Is there a logical way of understanding how randomness could agree with causality

  1. Feb 21, 2012 #1
    not to be impolite, but i truly view randomness in reality as something you can trick your kids into accepting along with santa, the tooth fairy etc.

    when compared to causality the idea of true randomness existing in reality seems incredibly weak to me.

    is there any logical way to reconcile the two?
  2. jcsd
  3. Feb 21, 2012 #2
    i guess not
  4. Feb 21, 2012 #3


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    Yes, there is. It is called Bohmian Mechanics. I would recommend you reading up on it a bit, and there are several here that can help you to understand it better. I should point out that has a drawback that may or may not bother you. In the Bohmian view, causes can propagate faster than light.
  5. Feb 21, 2012 #4
    Keep in mind that there is no consensus that physics is derived from logic, although I know of some efforts to do so. In such an effort, causality would somehow be linked to the relationship of material implication in logic, where cause and effect is just a form of consequences from premises. Time would just be a marker to indicate where one is in a sequence of causes and effects. I suspect that uncertainty would come in because there would be multiple sequences of events that get you from one cause to some final effect. We would not be able to say that any particular path was taken, so we would be left to calculate the probabilities for various paths. Hope this helps.
  6. Feb 21, 2012 #5
    i dont have to much of a problem with causes propagating faster than light, because to my knowledge there are tons of tiny wormholes on the quantum scale, which would allow for this, while large scale wormholes are not apparently common/spontaneously existent. that would explain why uncertainty only arises at a quantum scale in my mind. but thanks for the post. very interesting.
  7. Feb 21, 2012 #6
    you only see randomness as wrong because you're use to the macroscopic experience of determinism

    If you took a completely different standpoint, say an alien from a bizare world where there is something other than randomness and determinism, then determinism and randomness are both absurd.
  8. Feb 21, 2012 #7
    from wiki on bohmian mechanics

    The argument is that, because adding particles does not have an effect on the wavefunction's evolution, such particles must not have effects at all and are, thus, unobservable, since they cannot have an effect on observers.

    i like this interpretation, because it fits with my personal view that there is something bumping the curtain but we can never see it because we cant exit the universe, unless you like spagetti
  9. Feb 21, 2012 #8
    The point of randomness is that it isn't logical at all, there isn't an actual reason for it to occur, it just occurs, and when it occurs, it does nothing more than occur. I'm pretty sure our knowledge in QM has figured this out. The entire macroscopic world is built from randomness and chaos, we just don't see it as much because things happen to happen at a slow enough rate that we can predict where things are "probable" to be at large distances where the probability of wave-functions approach 0.
  10. Feb 21, 2012 #9
    It seems you were expecting someone to reply within the 41 mins you posted the thread and that comment. Patience is good.
  11. Feb 21, 2012 #10
    the probability of wave-functions approach 0.[/QUOTE]

    so wave functions are not 100 percent probabliistic?
    im ok with 99.999999999999999999999999999999999999999 percent likelyhood that the wavefunction is random. that could provide accurate qm predictions. maybe its asymptotic. 100 percent has serious implications.
  12. Feb 21, 2012 #11
    Randomness is only lack of information about the causes of events.

    Just like a shadow: it does not exist as an independent entity, but it is just absence of light.
  13. Feb 21, 2012 #12
    then why was possibly the grandest discovery in history derived from alberts logic?
  14. Feb 21, 2012 #13
    thats the way i feel and its about the most logically and mathematically sound statement than can be made.
  15. Feb 21, 2012 #14
    yes i was afraid that at 42 minutes the thread would randomly decay
  16. Feb 21, 2012 #15
    It seems people have different ideas of what the word "random" means. Personally, I don't like the definition of random as "lack of information", especially when you're talking about QM. I would define random as something which happens without cause, which I'm guessing is where the OP is coming from.
  17. Feb 21, 2012 #16
    i dont know how many pounds of acid i would have to do to believe we have a quasiexistence
  18. Feb 21, 2012 #17
    I think you've mis-understood the original statement. The wave function is what gives the probabilistic predictions for various measurement results on a quantum system. It does provide accurate QM predictions.
  19. Feb 21, 2012 #18
    yeah ur definition of randomness is what i would call true randomness, and is why i have issues with it...particles doing things because they want to....
  20. Feb 21, 2012 #19
    Reality is the ultimate arbiter between theories. And it was not clear from the beginning how one could derive physics from logic. So we have settled on using a trial and error method for finding mathematics for curve fitting the data from experiment. Thus our theories are contingent on future experiments not falsifying them. So we can never really know, by this method, that a theory is true beyond all doubt. The ONLY way to derive a TOE beyond all argument is to derive it from logic, the very rules of argument themselves.
  21. Feb 22, 2012 #20
    That's what I use to think when I was maybe 10-12, but some things just actually don't occur for a reason as well as the fact that there may be infinite factors or infinite levels of determinism making things on any specific level not deterministic or strictly incalculable with 100% accuracy, possibly because of fractal symmetry which mathematically goes on infinitely or an infinitely large universe. As QM explains, there is no real reason for a particle to appear in the place that it does, and you also cannot base where it will be next based on where it is now, so information to carry a cause-and-effect pattern is not preserved, and this is the realm that everything is built from.
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