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Modeling universes.

  1. Jul 14, 2010 #1
    Well, I discussed with a classmate about the wonders of this cosmos, watching "Into the Universe with Stephen Hawking", the alien chapter, which told about concepts of alien life in exoplanets. So we thought about concepts of "Exouniverses". I use this term because:

    Is it possible to model or predict (through mathematical models) universes with different physical constants?. I mean, considering a universe where the mass of neutrons, protons or electrons are different,the amount of matter vs antimatter or where speed of light is different (for example).

    Basically, as we make astrobiological or astrometeorological models (based in changes of atmospheric pressure, gravity or any other environmental feature), can we make cosmoligcal predictions or are we unable to do it because this "Theoricals Universes" are unimaginable.

    "Unimaginable" sounds ambiguous if we talk about relativity or quantum physics, I know, but let's think about this concept of modeling universes.
  2. jcsd
  3. Jul 15, 2010 #2


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    Well, theoretical physicists do this sort of thing all the time. The primary difficulty is that doing so necessarily invokes unknown physics, which means that all such attempts are currently only speculative (i.e. if the high energy laws of physics have such and such properties, then other universes might look like...). It's not terribly difficult to do, at least at a hypothetical level, but we just don't know enough about physics to say much of anything definitive about other universes.
  4. Jul 15, 2010 #3


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    There are about 26 [IIRC] fundamental constants in this universe. Generally speaking, if you tweak one, you tweak the others - often with unfortunate consequences for life in the universe. The constants in this universe are exquisitely fine tuned to permit it to survive this long without disintegrating, collapsing, or depleted of energy. Does that imply other universes? - unknown. Thus far all we can say is no other such entities are known or necessary to explain the properties of our universe.
  5. Jul 15, 2010 #4


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    Well, I think that the evidence of such things is most likely to arrive from discoveries in high-energy physics, in particular the nature of various sorts of spontaneous symmetry breaking.
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