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Fecund universes

  1. Feb 28, 2008 #1
    According to Lee Smolin's theory of fecund universes, baby universes sprout off of ours through black holes, yet their fundamental constants of nature are slightly different. How different are they? Are they so different that life as we know it would not be able to exist in them?
  2. jcsd
  3. Feb 28, 2008 #2


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    Last year Smolin posted a paper on the current status of his CNS conjecture. If you are interested you can look it up.

    As I understand it, the CNS conjecture is that the standard model and cosmology parameters are approximately optimal for black hole production (at or near a local maximum).

    This is the sort of prediction that we can test with current technology and, in a sense, have already been testing for over ten years. It requires understanding the physics of stellar collapse and making observations. So far the CNS conjecture is still standing.

    If, for the sake of argument, you accept the conjecture that the standard parameters (particle masses, coupling constants, cosmology constants...) are optimal for blackhole formation, then you can think up explanations HOW it could have gotten that way.

    One way is what you said, namely that the formation of a blackhole leads to a bigbang but possibly with SLIGHTLY different values of some parameters, which just BARELY change the abundance of blackholes in the next expanding region.

    this would promote evolution towards a set of parameters favoring blackholes and likewise (it turns out) favoring familiar carbonbase types of life but that is irrelevant to the conjecture. it just turns out that a universe tuned to produce a lot of black holes is also hospitable to carbonbase life on rocky planets around stable stars. Carbon chemistry helps in the generation of stars by providing pathways to radiate away heat. The fusion processes that yield heavier elements aiding star formation also provide the elements needed to make earthlike (rocky) planets instead of merely gas giants. So life is an irrelevant byproduct of an evolutionary process that favors the production of blackholes, in this scheme.

    I think the main question is not how to explain the odd coincidence that the parameters seem welladjusted for blackholes. the main question is whether they in fact ARE approximately ideal for that! If they are that would certainly be very strange and require some kind of explanation.
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