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Ripping apart baryons at the end of the universe creating new particles?

  1. Feb 7, 2013 #1
    The post might be in the wrong forum, and it's likely that a similar question has been asked earlier, but I couldn't find it with my feeble attempts at searching.

    It's apparently well known that you can't rip quarks away from each other and get singular quarks. The gluon bond gets stronger with increased distance, so when the quarks get sufficiently far away from each other, new quarks pop into existence due to the increased energy in the gluon bond.

    However if the universe ends with a so called Big Rip, where dark energy forces everything apart, would that also rip quarks away from each other? I keep imagining that the very act of separating the quarks from each other would create lots of new quarks/baryons. It might even total up in a huge amount of new matter, with the consequences that might have.

    I've never heard this mentioned anywhere, and it's been bugging me for a few weeks now. I'll be very glad for any answer to this. There's most likely a logical error somewhere, but I just don't see it.

    If one is to stretch this idea very far, it could open the possibility that the sudden increase in baryons could - through gravity - slow down the expansion of the universe. Then the dark energy would slowly increase the speed of the expansion and it all repeats, making the universe cyclic.
    Last edited: Feb 7, 2013
  2. jcsd
  3. Feb 7, 2013 #2
  4. Feb 7, 2013 #3
    Interesting article, thanks for the link. I see your point.

    I can't quite imagine how the strong force can be overcome seeing as its strength increased with distance, but then again when did stuff at the quantum level make sense.

    Its sort of counter-intuitive that the sun would be destroyed before the earth though. Is it the mass / size (extent) of the object or the strength of the gravity holding it together that makes the difference?

    If it's the second option, then we would have a few minutes to watch black holes get very interesting before dark energy ruins the day.

    Yes I know I'm really far off into the wild here, but I'm tired and my brain does whacky things.
  5. Feb 7, 2013 #4


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    I think part of the issue here is the divide between evidence-based cosmology and the more wildly speculative kind (which shades off into fantasy).

    We mostly deal with evidence-based here because that's what the professional research literature (peer-reviewed scientific papers) is largely about.

    At some point the evidence began to pile up against the "big rip" idea and it gradually began to be ignored in the professional research papers.

    It would have required that the cosmological constant not actually be a constant. But the evidence continues to mount up that it actually is a constant.

    I think most of the "big rip" papers were from before 2005. I don't recall seeing one for quite a few years now.

    One way to think about it is that the universe seems to be on track to a longterm percentage expansion rate of about 1/163 of one percent per million years. (give or take a little measurement uncertainty.)

    That is, in the long run any given distance between two widely separated observers will increase by that tiny fraction of a percent in a million years.

    You won't notice this on galactic scale. Galaxies don't experience this expansion effect because they are held together by their own gravity. Two observers in the same galaxy, say 100 thousand light years apart, will not notice any expansion between them. And of course on a SOLAR SYSTEM scale you wouldn't ever notice any expansion!

    Galaxies like Milkyway and Andromeda tend to occur in groups called clusters. This longterm expansion is too gentle to affect our modest-sized cluster, but I suppose it could effect much larger ones that are less securely bound together by their own gravity. In any case it will effect only very large-scale structure.

    This is what the so called "accelerating expansion of the universe" actually amounts to, in measured quantitative terms, as far as we can tell.
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