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Anthropic Multiverse Origin of Life

  1. Aug 23, 2005 #1
    "Quantum measurement by a self-replicating biomolecule was the key event that caused life to emerge."

    "Using the Many Worlds approach, peptide addition within the first (proto-) cell would have taken place, not in a classical universe, but within the multiverse of all possible states."

    "Each peptide addition was a multiple branch point where the growing peptide chain evolved in all directions simultaneously. The multiverse expanded with every addition to the peptide chain as the quantum tree of possibilities grew in every direction."

    "But once one branch lighted upon a self-replicating peptide, then quantum measurement would have become inevitable. Decoherence shattered the unity of the quantum tree, which split into 20^32 separate branches, each representing a different universe. Only one of the 20^32 descendent universes harboured the self-replicator, but in that one universe life emerged."

    The 20^32 is the amount of ways possible to put together peptides 32 amino acids long.

    Please comment on what you think about this interpretation of how life first emerged from this QM point of view. I couldn't get anyone in the Biology room to follow me, so I'll try my luck over here in the QM room. All of this was taken from molecular geneticist JohnJoe McFadden's book Quantum Evolution.

  2. jcsd
  3. Aug 23, 2005 #2


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    Yes, that's also more or less a potential view I have on these things. I tried to get a discussion started on the bio forum but it didn't really work out I guess.

    Ok, in the above formulation, there are some inaccuracies, in that "the quantum measurement would have become inevitable" etc...
    Decoherence is continuously at work, and nothing special happens when these peptides get into a long chain. The only point is that there are MANY PARALLEL branches, each evolving slightly differently, so in SOME of them, "life happened". So instead of having a "classical computer" figuring out replicating chains, you'd have a parallel quantum computer doing so.
    It doesn't have to be that way of course, but it is a way out of the "probability problem" in the devellopment of life. I'm absolutely no expert, but some claim that the probability for life to start on earth was way too low for it to be a reasonable explanation - however, that's assuming a classical approach. If you include the many many alternative branches in a multiverse, this increases vastly the probability of it happening in SOME branch (evidently the branch we're in!).
    It would have another implication: we would be alone in our branch (universe). Indeed, if the classical probability of life happening would be "rather high" so that it was likely to happen in the first billion years or so of the earth's existance, then it is also likely to happen elsewhere, so the universe should be full of life, so to speak. If however, the classical probability of life to happen would be zilch, and we needed the "branch factor" to make it happen, then there are of course other branches where it happened, but in THIS branch, it would probably be the only occurrence (within a decohered branch, things happen as if they are classical).
    It all depends on the estimated classical probability of life happening spontaneously.

    Of course, you don't need such an exotic explanation of course if the universe is infinitely large, because then the classical probability of life to happen *somewhere* is always large enough ; this would then follow the same argument as with the many branches.

  4. Aug 23, 2005 #3


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    This is very much consistent with what I was proposing at the end of this thread. The idea is that I think we can make reasonable inferences about the probability of there being extraterrestrial life if we have some basic information about the model of "universe" generation. I suggest various alternatives, including "evolving universes", random universes, and intelligent design. I included the possibility for many universes with random physical laws, but I now realize that I omitted an important one: many universes which are just different iterations with same physical laws. An example of such a situation would be the many-worlds interpretation of QM. In this model, I think the implication would indeed be that we are alone (assuming a finite universe), because of the anthropic selection bias.
    Last edited: Aug 23, 2005
  5. Aug 25, 2005 #4
    It shows that the author is as ignorant about how/why life first
    emerged as the rest of us. :-)
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