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Ultimate fate of the universe

  1. Nov 2, 2007 #1
    Hey, sorry to keep posting. It's just that my curiosity has spiked a bit over the last few days. I have another question.

    Does the vast majority of scientific evidence (theoretical and experimental) show that the expansion of the universe is speeding up? If so, is there any reason to believe that it would ever slow down?

    Or will it just keep expanding forever?
  2. jcsd
  3. Nov 2, 2007 #2


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    Good question, keeping asking them!

    The answer to this one is we don't know.

    The average density of the universe seems to be just greater than the critical density so that the universe will one day in the far future stop expanding and then contract.

    However that scenario is before Dark Energy enters the scene...

    It is thought Dark Energy that causes the cosmic expansion to accelerate has only been significant in recent history (since the epoch of objects seen at z ~1). Its equation of state, or behaviour, is still being determined. This effect could die away again in the future leaving the universe eventually to collapse, to continue to expand (the favoured option) or even to dominate everything in a 'Big Rip', ripping atoms apart from each other!

    On the other hand we could be mistaken, see the many discussions on these Forums about this subject.

    Last edited: Nov 2, 2007
  4. Nov 2, 2007 #3
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