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I Is something pulling our universe?

  1. Oct 4, 2016 #1
    I was watching a documentary about dark matter and dark energy (actually a couple of them) and how this is pushing the universe apart.

    I tried to find answers on if something could be pulling our universe apart rather than pushing. I couldn't find enything on this, but maybe someone here could give answers to this, if this could be an option and if someone's studied this?
     
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  3. Oct 4, 2016 #2

    phinds

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    No
     
  4. Oct 4, 2016 #3
    Why?
     
  5. Oct 4, 2016 #4

    PeterDonis

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    Dark energy has the effect of accelerating the expansion of the universe, whereas ordinary matter and dark matter have the effect of decelerating the expansion. Pop science treatments might use the terms "pulling the universe apart" or "pushing the universe together" to refer to these things, but that's not a very useful terminology because it invites the mistaken belief that there is something outside the universe acting on it. There isn't. That's why phinds answered "no" to your question.
     
  6. Oct 4, 2016 #5
    Ok. Thank you for your answer. I'm not a scientist, so I'm quite lost with all the terms.

    Now I might sound stupid, but has it been proven that there is nothing outside (our) universe? No other big bangs?
    Originally I was thinking if groups of universes could create their own gravitational fields and with these kinds of thoughts find an explanation that something (gravity?) could be "pulling" the universe (to all directions). Or maybe that the universe is falling (in all directions) accelerating.

    Maybe I'm just taking the short way to ask these here hoping for an answer and not finding out too much on my own... But all answers on this are appreciated!
     
  7. Oct 4, 2016 #6

    PeterDonis

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    How would you prove this? Anything we can observe is by definition part of our universe.

    You're thinking of the universe as like a planet or star, an isolated object embedded in some larger space. We have no evidence for any such larger space and no way of getting any; see above. So this doesn't look like a testable scientific model to me.

    What's more, this model of yours is not anything like the actual model that cosmologists use for dark energy and dark matter. So it's irrelevant to what you were asking about in any case. In the actual model that cosmologists use, dark energy and dark matter are part of our universe; they are not something outside it. That's why the answer to your question as you posed it is "no".

    And you have been given a short answer: no. If you want to know more, you're going to have to take the time to learn what our current cosmological models actually say. Ned Wright's cosmology faq/tutorial is one place you could start:

    http://www.astro.ucla.edu/~wright/cosmolog.htm

    In the meantime, this thread is closed.
     
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