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Is the nature of physics more probabilistic or deterministic?

  1. Feb 12, 2006 #1
    Is the nature of physics more probabilistic or deterministic?
  2. jcsd
  3. Feb 13, 2006 #2
    uh are you talking about the nature of physics..or the way humans attempt to understand the nature of physics.
  4. Feb 13, 2006 #3
    The nature of physics - the way it is ultimately understood by a participatory observer.
  5. Feb 13, 2006 #4


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    Quantum theory is a combination of deterministic (the wave function evolving unitarily) and probabilistic (the "measurement" where some eigenvalue of an operator acting on the wave function is instantiated in spacetime. This produces an "almost classical" world through the phenomenon of decoherence, but at bottom that world - THIS world - is only seemingly deterministic, up to a very high order of probability.
  6. Feb 14, 2006 #5
    Hello mr.Booda. The definition of Determinism is as follows (from wicepidia or some other spelling)

    It is my impression that classical physics is based on determinism or what is commonly known as cause and effect... or action and consequence. This study has gone on with this premise for millenia.

    Studies of quantum mechanics or events to this day appear to have found a potential theory suggesting that everything is happening simultaneously and that would be the root of a probabilistic approach to calculating what nature is up to. Because in a probabilistic mode of interpreting nature, there is no sequence and there is no heirarchy of events to explain the most recent of developments, just the probability of the developments given the parameters.

    What I wonder about the quote I gave is this: Isn't the "beginning of time" (as they say) outside of determinism and therefore doesn't that render determinism as a false philosophy?

    I can only say the above because of the part in the quote that says
    "If there has been even one indeterministic event since the beginning of time, then determinism is false.

    We could easily say, because of lack of information, that the big bang is indeterministic (until someone figures out how it came to happen)
  7. Feb 14, 2006 #6

    Well if an observer did not know much about physics it might say that its nature appears deterministic. On the other hand if it did know something of the nature of physics, it would say that its nature appears probabilistic.
    Since it seems not possible to know if there is more than one observer, you might as well choose your own answer.
  8. Feb 14, 2006 #7
    An observer from the Pyrrhonian skeptic's school would say: "Nothing can be known, not even this" and would remain in a state of perpetual inquiry. Lack of proof does not constitute disproof and lack of belief does not constitute disbelief. The Pyrrhonian observer would recognize that, in the future, there may be a determining factor discovered and verified concerning the origin and cause of the big bang. They would continue their inquiry until they were satisfied they'd found physical proof of a determining origin for "the beginning of time".

    The Pyrrhonian sceptic also would classify a belief in the dogmatism found in physics texts, bibles or other records that come unaccompanied by physical evidences as... a disease of the mind.

    Probabilism (from Latin "probare", to test or approve) is used only in the face of the absence of certainty. I would guess that an observer who has performed the various physical experiments of physics (that would classify them as a physicist), would, by the nature of the science, never rely on probabilism or assume one thing over another in the face of uncertainty. They would, not unlike a Pyrrhonian sceptic, continue the inquiry.
  9. Feb 15, 2006 #8
    Is there any similarity between the indeterminism inferred beyond the cosmological event horizon(s) and that of the unmeasured (quantum) universe?
  10. Feb 15, 2006 #9


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    No. The "beyond the horizon" world is just something we can't see, an accident of where we happen to be. They can't see us, either. While (according to modern physics anyway) quantum uncertainty is a deep property of the universe.
  11. Feb 15, 2006 #10
    Is "quantum uncertainty" similar to potential?:uhh:
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