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A Universe That Is More Life-Producing?

  1. Feb 8, 2005 #1
    Now imagine for a second that there are countless other universes, ours is only one out of many. Now subtract the dead universes, which is probably the majority of the universe, and we are left with life-producing universes. We know that our universe could have life in it (we are living proof) but the universe may not produce alot of it, could there be a type of universe that could produce more life than ours, a universe that is teeming with life? and when I say life I mean life as we know it because other universes could have other laws of physics, dimensions, etc. and in turn have other types of life that we cannot even comprehend.

    Or is our universe the best of the best?
  2. jcsd
  3. Feb 9, 2005 #2


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    Whereas the optimistic cosmologist thinks so, the pessimistic one fears he may be right! :wink:

  4. Feb 9, 2005 #3
  5. Feb 9, 2005 #4
    Well, Gold Barz, a couple of questions...

    1) Define "other Universe". Are you speaking with reference to local universes within one big "Universe" or many alternate realities (like the "multiverse" interpretations of Schrodinger)?

    2) Are you assuming an infinite number of such universes, or are they finite (in which case, we could still (statistically speaking) be the only one with life)?

    3) If you are referring to life as in Earth-life (just prokaryotes and eukaryotes), then had you considered the possibility that the number of dead solar systems needs to be great, in ratio to the number of living ones? After all, we get the material to "build" Earth-life from the explosions of old stars.
  6. Feb 9, 2005 #5


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    Life requires a very narrow set of conditions to allow the necessary complexity to develop. These are the 'Anthropic coincidences'.

    However once formed the processes of evolution drive those existing life forms to 'fit' the available niches. Treating the whole universe as a 'niche' we might conclude that our universe is 'the best of the best' for those life forms that have evolved within it.

    Of course there is a tremendous variation of environments within our universe and probably only a very small sub set is suitable for any life forms, but we do not know enough about exobiology to evaluate that statement.

    Other different universes may be 'the best of the best' for a different form of life, however that might be defined, but such ideas are pure speculation.

  7. Feb 9, 2005 #6
    Well I am talking about carbon-and-water based life in other universes with similar laws of physics but just tweaked a little bit for it to more life-friendly (teeming with life), and I am talking about universes within a bigger, greater multiverse, each universe is different from each other in complexion, laws of physics, dimensions, etc because if it wasnt then it wouldnt really be different universes

    And yes I know that dead star material is essential so I think every universe with the potential for life would have that.
  8. Feb 10, 2005 #7
    There was a recent program on british tv (called 'what we still don't know')that touched upon the multiple universe extension of anthropic principle. Basically, it concluded that other universes may indeed be more favourable to life. It then extended this by saying this life could have theoretically evolved at a faster pace than our own and, in doing so, could of reached a level of 'super-intelligence' that we can't comprehend. This opens up the posibility that we could be just lab experiments of super-intellient beings from another universe. Beings that we might percieve as gods even. A vicious circle of anthropic principle kinda.
    Doesn't bare thinking about too much really:frown:
  9. Feb 10, 2005 #8
    I think that the fact that the odds of life emerging in the universe is very slim makes a good case for multiple universes...alot of dead universes, but there are some life-bearing universes too, we are in one obviously
  10. Feb 11, 2005 #9
    I think you have it back-to-front slightly. Our universe is actually incredibly fine-tuned to allow life. Although life on this planet has struggled to survive at times, the universe in general, through the constants that govern it's very basic physics are tuned to several decimal places to allow life, ie if these constants changed only slightly we'd not be here.
    However, the anthropic principle suggests that it would be like that, because we are here to observe it. If life didn't exist here, chances are it would not be fine-tuned.
    But you can extend anthropic principle to say that there must be an infinite number of unsuitable universes that lie outside ours, for us to be in the fine-tuned one.
    It's purely in the realm of philosiphy though, since we will never be able to prove these other universes exist.
  11. Feb 11, 2005 #10
    And yet, if there are many of them, and there is some way to draw a line such that two of them are at endpoints of that line, then aren't they actually within the same spacetime?

    Well, what I was specifically wondering about was whether there was a necessary ratio (perhaps with consideration to how scarce elements other than H and He are).
  12. Feb 11, 2005 #11
    That is what I meant, that the universe is so incredibly fine-tuned and the odds are against a fine-tuned universe...that makes me think about other universes, with most dead and some with life in it
  13. Feb 11, 2005 #12


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    Be very careful with the Anthropic Principal. There are copious numbers of soft-celled life forms in the deepest trenches of our oceans, where most other known life forms would perish instantly. It may be that in any universe that can exist for a sufficient time, life will evolve, even in the most extreme environments. Could some form of creature or some self-perpetuating construct exploit the energy differentials in inter-galactic space? Think a bit before you say no. Human self-absorption and reflection is a strength, but it is also potentially blinding. The universe was here a long time before we were, and it will be here a long time after we are gone. Yes, we seem to exist in a universe that was custom-made for us, but those soft-celled animals at the bottom of the Marianas Trench are in a universe that was custom-made for them, too. Despite the enormous differences between them and us, we are creatures of the Earth, and we may be a whole lot more similar to them than we are to any extraterrestrial life that we might encounter.
  14. Feb 11, 2005 #13


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    The multiverse is a workable hypothesis that explains the anthropic coincidences as a selection effect; however, show me one.

    Last edited: Feb 11, 2005
  15. Feb 11, 2005 #14
    You have got a point there, but could these super extreme extremophiles survive in a universe where even an atom is unstable?
  16. Feb 12, 2005 #15


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    The most basic definition of life - self replicating 'entities' - requires complexity. Complex organisms requiring multiple of far-from-thermal-equilibrium chemical processes demand a very narrow set of physical parameters to exist. Stability of atoms - let alone complex molecules, or other equivalent information bearing systems - would appear to be a minimum necessary requirement.

    Last edited: Feb 12, 2005
  17. Feb 12, 2005 #16
    I see, so most universes will still be life-less (atleast life as we know it) huh?
  18. Feb 12, 2005 #17
    Guesstimate a percent of how many universes would have the potential to sustain life

    and I think that the discovery of extremophiles really greaters the percent...scientists say that we were extremophiles once
    Last edited: Feb 12, 2005
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