Wednesday, August 08, 2007

(Long) quote for the day: ...Our universe does seem singularly congenial as a home for intelligent life. L.J. Henderson's Fitness of the Environment extolled the remarkable life-enhancing properties of water, as well as pointing out the unique properties of the carbon atom, including the fact that carbon can bond with itself in a vastly larger number of combinations than any other atom. It is this wonderful property that makes complex organic chemistry possible.

Of course, these unique properties would have been little avail in fostering life, had it not been for the substantial abundance of oxygen and carbon. But since hydrogen and oxygen rank first and third, respectively, in cosmic abundance, water is guaranteed to be present throughout the universe, and carbon comes in fourth in order of cosmic abundance. If we were allowed to think of God in anthropomorphic terms, we would say, "Good planning!" Curiously enough, neither oxygen nor carbon emerged in the first three minutes of the Big Bang. At first glance, this might be labeled God's Goof. That's how the physicist George Gamow felt when he discovered the flaw in the nature of the light elements that prevented the heavier elements from forming. In the first minute of the Big Bang, energetic photons were transformed into protons, which fused into deuterium (nuclear particles of mass two), tritium (nuclear particles of mass three), and alpha particles (which would serve as mass-four nuclei of helium atoms). But there was no stable mass five, so at that point the fusion process stopped, well short of the twelve needed for carbon or the sixteen for oxygen...

...But far from being a design flaw in our universe, the absence of mass five seems essential to our existence. The lack of a stable mass five means that the element-building in the stars takes place as a two-step process: first, hydrogen is converted to helium, in the hot nuclear cauldrons at the cores of the stars; and then, once helium is abundant, it is built up into heavier atoms, in a second process. Because helium has a mass of four units, the fusion of two or three or four helium nuclei results in atoms of mass eight or twelve (carbon) or sixteen (oxygen), thus skipping over the unstable mass five. This second process requires a much higher temperature in the stellar interiors, one that is not reached until much of the hydrogen fuel has been exhausted--in the case of a star like the sun, only after about ten billion years. This guarantees a long, steady lifetime for sunlike stars. It is of course this tedious process that provides the stable solar environment in which the evolutionary biological sequences can work themselves out.

If mass five was not absent, that could not happen. Suppose that mass five were stable. Then, in the opening minutes of the universe, characterized by the overwhelming abundance of protons (each with a mass of one unit), atom-building could have taken place as mass increased by steps of one, right up the nuclear ladder toward iron. This would have left no special abundance of carbon (mass twelve) or oxygen (mass sixteen) , two essential building blocks of life...What at first glance appeared to be God's mistake turn out to be one of the Creator's most ingenious triumphs. (pp. 52-56 in God's Universe by Owen Gingerich, Professor of Astronomy and History of Science, Harvard University).


  1. hicsto8:23 AM

    The universe is also 'designed' in such a way that life on earth is periodically decimated (and worse) by asteroids. The human race could be wiped out tomorrow by one or made to suffer by one in ways it's difficult to contemplate. The 'It's all here for us' attitude is dangerously complacent. Literally so.

  2. dearieme11:52 AM

    So life evolves to suit its circumstances. Then one of the less reflective samples of life says "My, isn't it striking how well the circumstances suit us". How very remarkable.

  3. hictso: Gingerich's sort of argument suggests that life is fragile, like walking a tightrope, and not secure.

  4. dearieme: Gingerich's argument is that the way that the universe unfolded was weird and didn't follow the parsimonious, logical stair-step process of fusion of single protons, and that very weirdness is what made life possible.

    Although Gingerich is not arguing it, being amazed at one's existence, or its various properties, is not a manifestation of a lack of reflection: Aristotle wrote that it is the origin of philosophy. Bovines take their existence for granted.

  5. dearieme2:51 PM

    Oh all right: make that a lack of intelligent reflection. And as for "the way that the universe unfolded was weird "; compared to what, for heaven's sake? It's the only one we've got.

  6. dearieme: True, this universe is the only one we have (at least have access to) but it is not the only resource we have to make sense of things. Math is not inferred from nature, for instance, but we've discovered it and use it to great profit. Logic is another example. As Kant explained, many of the tools we use to gain knowledge are in our minds and not in objects. We possess much more than passive receptivity to sense data.

  7. Anonymous6:40 AM

    Very interesting. But the conceit about "the opening minutes of the universe" is absurd. I don't deny that scientists can go very far towards explaining what is happening inside our box called the universe. But to pretend to know when, or how, the box came into existence, is hubris of the most unscientific type imaginable. The "leap of faith" required to answer this question is no different in science as in religion.

    Steven Warshawsky

  8. hicsto10:17 AM

    hictso: Gingerich's sort of argument suggests that life is fragile, like walking a tightrope, and not secure.

    I've not read his book, but what you quote suggests his 'tightrope' is certain aspects of physics and chemistry which could have been different. But now that they're here, life seems to be able to depend on them absolutely. What it can't depend are higher-order aspects of its environment, which could become zoophobic at any moment. That seems an odd way for the Designer to operate.

  9. That seems an odd way for the Designer to operate.
    I don't think you can claim to know the mind of God, honestly. Even if there is an ominpotent designer there's no guarantee he's the moralistic sort we see in the Bible. My personal theory is that he's a sadist who enjoys watching humans kill each other, we certainly seem to do it a lot.

    The objection to the anthropic argument is that we're only able to observe universes we exist in; there could be lots of other universes that haven't evolved life and there's no one around to talk about it.

    I believe they've done this sort of argument for most of the major physical constants.

    If you find this line of thought convincing, there's a nice set of examples of how the world would be uninhabitable with different properties:
    It's neat stuff, actually.

  10. Of course we're going to see a miraculous set of coincidences since we are, by definition, living within a world, solar system, and universe in which life is possible. Most of the universe (or, potentially, universes) is sterile. There are entire galaxies where conditions are too hostile for life as we know it to exist.


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