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Missing Matter?

  1. Nov 6, 2007 #1
    This came to me the other day.
    Im a total layman, so forgive the language, just an idea, and thought I'd ask far cleverer ;) people than me.

    I've read again and again about how there isn't enough matter in the universe for gravity to stop everything flying apart rapidly. The hunt is on it seems for this missing matter.

    But it occurred to me, maybe people are measuring the universe wrong?
    Instead of it being like a big ball, with smooth edges.
    What if it is Spikey? Like a hedgehog or big round starfish?
    With some galaxies shooting out faster than others, leaving big gaps of nothing between.

    That would massively reduce the 3dimensional area of the Universe, and thus reduce the amount of matter required for gravity to be able to do its thing.

    What do people think? Is it a go-er? Or am I just nuts? (not that I mind nuts, I always suspected the insane have far more fun.)
  2. jcsd
  3. Nov 6, 2007 #2


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    Among the things leading to the dark matter hypothesis is the fact that our galaxy (like all others) doesn't have enough ordinary matter to hold it together.
  4. Nov 7, 2007 #3

    Chris Hillman

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    Maybe not nuts, but not sufficiently thought through?

    I can't be completely sure I understand your vision, but this doesn't sound consistent with observation.

    Sounds like you might have heard somewhere that a "spiky" ink blob in a pool of water has greater surface area than a round blob having the same volume, and inferred that of two blobs having the same surface area, a round blob has the larger volume. Is it possible that you are trying to visualize the Hubble expansion as an ink blob (fed from a pipe from the surface) which is increasing in volume and expanding in a clear pool of water? If so, the Hubble expansion is not like a localized "explosion" of galaxies flying into previously empty regions of spacetime.
    Last edited: Nov 7, 2007
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