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  1. 23 Mar '15 16:43 / 3 edits
    they claim their calculations suggest that the universe will collapse in a few tens of billions of years or so.

    http://phys.org/news/2015-03-universe-brink-collapse-cosmological-timescale.html

    Is this a sensible scientific theory?
    Or is this wildly over-assumptive nonsense with very little chance at best of being true?

    If I am reading this right, the theory assumes the existence of dark energy? If so, then one minimum thing you would have to assume to be credible as a prerequisite before you can give the theory any credence is that dark energy credibly exists.
  2. 23 Mar '15 17:31
    Originally posted by humy
    they claim their calculations suggest that the universe will collapse in a few tens of billions of years or so.

    http://phys.org/news/2015-03-universe-brink-collapse-cosmological-timescale.html

    Is this a sensible scientific theory?
    Or is this wildly over-assumptive nonsense with very little chance at best of being true?

    If I am reading this ri ...[text shortened]... a prerequisite before you can give the theory any credence is that dark energy credibly exists.
    I wouldn't think so. But just live and see...
  3. Standard member DeepThought
    Losing the Thread
    23 Mar '15 17:45
    Originally posted by humy
    they claim their calculations suggest that the universe will collapse in a few tens of billions of years or so.

    http://phys.org/news/2015-03-universe-brink-collapse-cosmological-timescale.html

    Is this a sensible scientific theory?
    Or is this wildly over-assumptive nonsense with very little chance at best of being true?

    If I am reading this ri ...[text shortened]... a prerequisite before you can give the theory any credence is that dark energy credibly exists.
    It relies on dark energy existing, and it relies on dark energy "sequestering" which I assume is some way the dark energy becomes normal energy. So the energy density of the universe shows a net increase over time and eventually starts dominating over everything else. They are making some claims of naturalness. I haven't looked at their paper, I don't think it's ridiculous, once you filter out the standard over-hype it's reasonable enough it just depends on a lot of assumptions about dark energy.
  4. 23 Mar '15 18:07 / 1 edit
    Originally posted by FabianFnas
    ... But just live and see...
    what? For tens of billions of years? I like your proposal.
  5. Standard member sonhouse
    Fast and Curious
    23 Mar '15 18:18
    Originally posted by humy
    what? For tens of billions of years? I like your proposal.
    They seem to be just doubling the present age of the universe to arrive at their figure but why wouldn't it not be related to when the acceleration started, allegedly about 5 billion years ago. If that is correct, wouldn't that indicate a doubling of THAT number, so if it has started collapsing, maybe it will complete the process in 10 billion years instead of 25 or 30 billion years?

    Won't make much difference to the solar system or humans of course but just wondering.
  6. 24 Mar '15 06:34
    Think of it for a minute...

    Suppose that the accelerating universe is nothing but a speculation for a while, and the expansion of the universe expansion is only because gravitation and nothing more.

    The age of the universe is between 13 and 14 million of years (they say) and it is still expanding. How in hell could it suddenly make a stop and turn it into contraction? And then contract to a Big Crunch? And it will do this in only a few tenth of billion of years?

    If I would have to guess - no less than 100 billions of years, probably much more, and with no respect for a presumed accelerating universe.
  7. Standard member sonhouse
    Fast and Curious
    24 Mar '15 09:39
    Originally posted by FabianFnas
    Think of it for a minute...

    Suppose that the accelerating universe is nothing but a speculation for a while, and the expansion of the universe expansion is only because gravitation and nothing more.

    The age of the universe is between 13 and 14 million of years (they say) and it is still expanding. How in hell could it suddenly make a stop and turn i ...[text shortened]... billions of years, probably much more, and with no respect for a presumed accelerating universe.
    Ok, but you wrote the age at 13 million, should be 13 billion. I know it was a typo So we have narrowed down the possible big crunch to a few hundred billion years. I can live with that
  8. 24 Mar '15 15:15
    Originally posted by sonhouse
    Ok, but you wrote the age at 13 million, should be 13 billion. I know it was a typo So we have narrowed down the possible big crunch to a few hundred billion years. I can live with that
    Sorry if I wrote millions. I think everyone discovered this typo. Thank you sonhouse for pointing this out!

    In my own more or less humble opinion, I don't really believe in an accelerating universe. Time will tell if I'm right.
  9. Standard member sonhouse
    Fast and Curious
    29 Mar '15 13:57
    Originally posted by FabianFnas
    Sorry if I wrote millions. I think everyone discovered this typo. Thank you sonhouse for pointing this out!

    In my own more or less humble opinion, I don't really believe in an accelerating universe. Time will tell if I'm right.
    I'm still pushing for the multiverse solution. If that proves to be right, and we figure a way to survive going through a black hole we might survive the end of our universe. Grasping at straws?
  10. Standard member DeepThought
    Losing the Thread
    29 Mar '15 15:09
    Originally posted by FabianFnas
    Think of it for a minute...

    Suppose that the accelerating universe is nothing but a speculation for a while, and the expansion of the universe expansion is only because gravitation and nothing more.

    The age of the universe is between 13 and 14 million of years (they say) and it is still expanding. How in hell could it suddenly make a stop and turn i ...[text shortened]... billions of years, probably much more, and with no respect for a presumed accelerating universe.
    The idea, as far as I can make out I haven't read the paper, is that dark energy drives the accelerating expansion. It is sequestered by some mechanism and turned into ordinary matter, this stops the expansion and the universe collapses into a big crunch.