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A question on the big bang

  1. Aug 14, 2011 #1
    I recently watched curiosity and i have been having a hard time grasping how it describes the creation of our universe. As i understood the theory is that the laws of our universe say that a particle of subatomic or less size can pop in and out of existence and so the universe itself could do the same because it was so incredibly small and the laws of our universe say it is possible it could do so. My question is why would the laws of the universe apply to a lack of existence?

    My understanding is that the universe didn't exist and neither did anything else then it came into existence spontaneously with no time before it. So i would think the laws that govern our
    universe must therefore have applied themselves to the lack of existence for the universe to be able to pop into existence spontaneously like that, which would only be possible with the laws we now have discovered in place despite the lack of an existence for them to govern.
  2. jcsd
  3. Aug 14, 2011 #2


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    I'm not totally sure how to answer your question. It doesn't make much sense to talk about what was happening before the big bang. The universe existed starting at time = 0. To say something "didn't exist" before that doesn't make sense because one might say that the very concept of existing means it is part of our universe. You have to be very careful with what words you use and what the words you use imply. For example, if one were to ask what exists outside the universe... well, to me, that doesn't make sense because if something existed outside the universe, it would be part of the universe itself (when I say universe, I mean the more strict definition of "everything", and not just "observable universe" that many think of)! Thus, the question wouldn't make sense. Another example might be asking yourself, as you sit at the North Pole of Earth, "where is north?". You're at a point where that question no longer makes sense and has no meaning. The word we used, "north", apparently has a limited domain of applicability.

    I'm not sure that really even answers or hints at what might be causing your confusion.
  4. Aug 14, 2011 #3
    I think i understand what your saying, but if i do then to understand the big bang theory I have to accept that the universe and the laws that govern it and allow it to spontaneously appear from nothing came into existence at once together. i may not be explaining my question very well or just misunderstanding you but the part that I'm having trouble with is that the laws that say the big bang could happen would have had to create themselves in the same way the universe created itself as well for the big bang to happen and create the universe we have now that these laws govern.
  5. Aug 14, 2011 #4


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    Well, such ideas of things spontaneously appearing from "nothing" aren't new in physics.

    Also, what exactly caused the big bang is really speculation still. We don't have a theory of quantum gravity which would tell us possibly more of what may have happened at the big bang. So all you have is some very very smart people taking educated guesses using everything we know about physics to answer a question we really can't know the answer to by experiment. But until we get to the point we can manufacture entire new universes, I don't think we can know the answer :P
  6. Aug 14, 2011 #5
    Alright i think i understand what you are saying now, thanks for clearing that up it had been driving me insane.
  7. Aug 16, 2011 #6
    Idk, that second part was my exact same question in another thread.

    It doesnt make sense right?
  8. Aug 16, 2011 #7


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    The obvious problem with quantum fluctuation emergence of a 'universe from nothing' is what 'fluctuated'? Or, can 'nothing' fluctuate? That is a good question and, like most good questions, the answer is unclear. Similarly, why did it fluctuate when it did and not 'sooner' or 'later'? Questions such as these are what cause physicists to entertain the existence of unobservables and propose imaginative and evasive alternative theories. Nothing wrong with that so long as you concede it is just a guess.
  9. Aug 17, 2011 #8
    I just watched the recording of Curiosity. It makes great sense and I see where he is coming from, but for me it just opens more doors to more questions like if there was no time at the beginning, then the BB should have never have happened because time wasnt in play.

    It really blew my mind and I really liked the different point of view. It makes me want to read his book and what he says about religion. Thats all I will say about that.
  10. Aug 30, 2011 #9
    Correct me if I am wrong but if particles "pop in and out of existence" "all the time". As seen on a molecular level. And the singularity consisted of all matter, why do objects larger than those of the molecular level not "pop in and out of existence'? Something as large as a rock, tree or planet?

    Science is alway evolving. Before the electron microscope scientists thought and taught that a single cell was as small as things could get. The scientists of today say that on a sub atomic level they see particles pop "into and out of existence." This popping into and out of existence seems to go against other laws of nature and physics. Perhaps a recording or measuring device has not been invented yet to realize that these particles are actually traveling from place to place not "popping into and out of existence."

    Without modern equipment it would seem as if light traveled instantaneously not at 186.000 mps.
    Without the right equipment is this the possible reason such intellectual giants come to their hypotheses. Some hypotheses that go against other laws of psychics and nature?
  11. Aug 31, 2011 #10


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    Religion, like science, is merely a belief system. Science has the advantage based on observational evidence. That renders religion factually unsupported, but not invalid.
  12. Aug 31, 2011 #11


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    I really don't think one should classify science as a belief system; it is really nothing of the sort. It is a method for gaining an understanding of the natural world.
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