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Probability of Existence

  1. Aug 17, 2011 #1
    Hi everybody, I was wondering this:

    "What is the probability, given all the information (including scientific evidence and accepted theories), of having this existence (I'm not talking about life and consciousness) just right how it is?"

    I have no idea about any kind of research or study area focused in this problem.
    As my own interpretation, just intuitively, I though about that the first moments of our existence (or reality?) where dominated by Quantum Fluctuations, so maybe Quantum Mechanics could answer this question.
    Sorry for the lack of rigurosity of my interpretation, but I'm just an amateur by the moment.

  2. jcsd
  3. Aug 17, 2011 #2


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    The probability is 1, since we are here!
  4. Aug 17, 2011 #3

    :redface: pretty much haha. How would you even figure that out mathematically ??

    Mind = Blown
  5. Aug 17, 2011 #4


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    I'm not sure what exactly the nature of your question IS really, but if you look at all of the physical constants that have to have values inside a VERY narrow range, all at the same time, to their present values, the probability of that happening seems to me to be very close to zero. Obviously it ISN'T zero because we're here, but it's what gives rise to the the anthropic principle.
  6. Aug 18, 2011 #5
    Could we say that we are some kind of statistical error (as a existence)?
    Maybe statistical errors so far, are the main enigma of all existence.
  7. Aug 18, 2011 #6


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    I don't really know HOW to think about it. I REALLY dislike the idea of multiple universes, but this issue is the one thing that makes me think perhaps that is the way things work. If it is, then we are not at all a statistical error, we are just the particular one of the multiple universes that happens to have the particular set of physical constants that we do.

    OR ... (and I REALLY prefer this one) maybe there is some underlying reason in physics that we don't yet know of that makes it such that all those physical constants are what they are.

    Many folks lots smarter than I am have thought about all this much more than I have and it will be marvelous if we ever get a definitive reason but so far it all seems to be just speculation and argument.
  8. Aug 18, 2011 #7


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    Emphasis mind: Can this actually be said with any certainty? Perhaps the values that we see could not have been anything different. For example; when a large protein folds there can be more possible folding combinations than there are atoms in the universe yet almost every time proteins fold the correct way. The reason being is that just because there are a number of possibilities does not make all those possibilities equal, likewise the constants could be as they are because there is little chance they would be anything else.
  9. Aug 18, 2011 #8


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    Please read the middle sentence in post #6
  10. Aug 19, 2011 #9
    the first poster's answer was the only correct one.

    once the terms "probability", "statistics" or "error" are introduced into a discussion, then the fundamental model is the relationship between a singular occurrence and a population or sample of occurrences.

    note the plural.

    sometimes the occurrences are literal -- red marbles and white marbles in a large urn, and you draw one marble from this urn ... this is how probability theory is typically introduced. sometimes the occurrences are estimated by a mathematical formula that describes a distribution, and calculations are made in relation to this distribution; the mathematical formula needs to be motivated by empirical considerations.

    we have *no* evidence of alternatives here, no physical sample of universes of worlds to count up as a population or sample, no cosmological theory that produces a finite distribution of universes or worlds that we can use in place of a physical collection of universes.

    the question itself is meaningless, because it fundamentally doesn't understand what probabilities are. and this is a serious problem in science education in the usa: a failure to teach how science asks questions, and a failure to appreciate that questions you cannot ask in scientific terms have no scientific answers.
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