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Cause of origin of Universe

  1. Oct 20, 2011 #1
    If the universe was smaller than a proton before the big bang, can we say that the question of the cause of bigbang is meaningless (i.e. it happened without any logic)?

    I say this because sub atomic particles keep on popping in and popping out of existence without any underlying cause. Or is science missing something? Is it that this quantum randomness may have some hidden causes ( i.e. cause and effect relationships)?
  2. jcsd
  3. Oct 21, 2011 #2
    asking what is 1/x at x=0 is also meaningless but that doesnt mean that math is "without any logic".
  4. Oct 21, 2011 #3
    quantum mechancs provides a "cause"...quantum fluctuations...for virtual particles...

    so I disagree with your premise and your conclusion.

    Try reading here:

    and here :


    where the mathematic underpinning is mentioned:

    But so far there is no proof, no incontrovertible evidence, no consensus, on exactly what caused the big bang. I don't think anyone has a theory yet on whether virtual particles actually "caused" the big bang...
  5. Oct 21, 2011 #4
    The size of the universe before the Big Bang is only speculated no one really knows how big or small it was. The cause of the Big Bang or inflation would not be dictated by the size of that singularity. Everything has a cause so if particles are popping in and out of existance (quantum fluctuation) then there is a cause. And there is much speculation it.
  6. Oct 21, 2011 #5


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    This is actually very much in line with some popular theories of the origin of the BB. It is speculated that, indeed, it erupted from some sort of proto-quantum-fluctuation state that normally collapses back on itself almost instantly - like virtual particle pairs do - but in this case, for some reason did not collapse back to nothing, and instead expanded rapidly, creating the entire universe.
  7. Oct 21, 2011 #6
    If the Universe is spatially flat and has infinite mass and energy then the OU may have been smaller than a proton but the entire U would still have been infinite. At least that is how I understand it.
  8. Oct 21, 2011 #7


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    Those are some big 'if's. Why would it have infinite mass and energy?
  9. Oct 21, 2011 #8


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    I take this two ways, Dave. First, I think things DO have reasons, even if we don't understand them. Second, in QM, a valid reason is "s*** happens". :smile:
  10. Oct 21, 2011 #9
    Suppose the reason for expansion is found as told by dave, what would be the reason for that reason. And so on.....

    Is origin of of this universe really that simple a matter? Or we have to retrace our steps infinitely?
  11. Oct 22, 2011 #10


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    It is called "First Cause". And we may never know the answer.
  12. Oct 22, 2011 #11
    Your "first cause" seems to be above reasoning and science even, that it does not require any "cause" for its occurenece. I think we should shun science and start believing in magic.LOL
  13. Oct 22, 2011 #12
    Upon rereading, I see I should have also said I agree with this part of the OP:

  14. Oct 22, 2011 #13
    its not that we cant find the answer.
    its that we are asking th ewrong question.

    asking what is the cause of the first cause is simply a meaningless question.
  15. Oct 22, 2011 #14


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    I agree our idea of cause and effect may have to be rethought when it comes to the origin of the universe, but simply asking what caused the BB is not meaningless, in my view.
  16. Oct 22, 2011 #15


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    I think there MAY be meaningless questions, but that certainly isn't one of them. I agree w/ what Dave said.
  17. Oct 22, 2011 #16
    Yeh, there is no reason we can't figure out what caused things in our universe but before and beyond are another thing, Who knows
  18. Oct 22, 2011 #17
    Ever heard of deep space imaging? If you believe that at some time in the past, our universe was a point which exploded and you know that light travels at a finite speed, then logically, the deeper you look into space, the further back in time you are seeing. Therefore, upon the deepest glance into space, we would inevitably have to see the big bang from within it. Either we are seeing the ultra-dense universe in that time, or we would be seeing outside our universe. The latter is simply impossible by our definition of the universe.

    the question I wonder is why haven't we seen something like this. Perhaps things are not so cut and dried as we assume they are.
  19. Oct 22, 2011 #18
    I am reminded of the kid who told the pizza man that he wasnt that hungry so he should only cut the pizza into 6 pieces rather than 8.

    it makes no difference how you cut it, its still a meaningless question.

    if the first cause had a cause then it wouldnt be the first cause.

    we may ask what the first cause was but we cant ask what caused it.
  20. Oct 22, 2011 #19


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    We do.

    It's called the cosmic microwave background radiation or surface of last scattering. This is the actual remnants of the Big Bang.
  21. Oct 22, 2011 #20
    Interesting. didn't know those were associated
  22. Oct 23, 2011 #21
    not any one seeing when universe is forming. It is the imagination of big bang which is correct w.r.t all the theories of science that is why to put question what is the first cause is baseless
  23. Oct 23, 2011 #22
    It is same as the question which one arrive first?
    An egg or a hen
  24. Oct 23, 2011 #23


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    The egg came first.

    The planet's first ever chicken was born from an egg, which was laid by a proto-chickenosaurus.

    Last edited: Oct 23, 2011
  25. Oct 23, 2011 #24


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    Science deliberately sidesteps the 'first cause' issue because it belongs to philosophy. Science is very good at 'what' and 'how', but, not 'why'.
  26. Oct 23, 2011 #25
    Who said there had to be a 'first cause'?

    'First cause' is a contradiction to Newton's third law. If there is an effect - big bang, there must be a cause. And there must have been a cause to cause the big bang, and so forth. It is an unending question of why's, the only conclusions are that this reasoning is false, or there is no 'beginning' and therefore an infinite string of causes.

    This law is the basis for all our logic - or our logic is the basis for this law - either way, it is our only way of understanding things - which is in terms of 'cause and effect'.

    If A, then B... if B, then C... and if B, then we can say C will occur, and that A must have preceded B if nothing else causes B.

    Either this logic holds infinitely and there is no beginning, or our logic is flawed.

    'Since the universe exists, it must have been created, and something must have caused that to create it...' - to deny this question is to deny any other question based on the logic of cause and effect.

    There simply cannot be special cases in this logic. It is either true, or it is not. There are no exceptions.

    Your pizza scenario is irrelevant. Clearly, those are two independent things. However, the creation of the universe and the cause of that cause are not independent - by definition one effects the other.

    I would say more about a theory which supports the big bang and evidence for it, but argues it is not the 'creation', but that is for a different thread.
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