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Science Frontiers ONLINE No. 121: Jan-Feb 1999 |
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Is life a transitory phenomenon?
We don't mean just life on earth, where it has hung on for a couple billion years, but life anywhere in the universe.
Many cosmologists advance the socalled Anthropic Principle, which states that the physical constants of nature are honed to just the right values to make life possible. If the charge on the electron were a little less or the properties of carbon a bit different, life could not exist. The Anthropic Principle seems to imply that the universe was designed for earth life. But "design" is a bad word these days. It is redolent of purpose and a supernatural being. Suppose, though, that the Anthropic Principle is correct but only in our part of the cosmos and only for a little while. If the constants of nature are not really constant, life could be just a transitory phenomenon, flaring up here and there wherever conditions are ripe and the Anthropic Principle reigns. The cosmos as-a-whole might be lurching toward other goals or, perhaps, toward nowhere in particular.
Enough philosophy! A team of Australian astronomers, led by J.K. Webb, has been trying to determine if the famous fine-structure constant of physics has really remained constant throughout the 12-billion years or so of the universe's history. The fine-structure constant is dimensionless and almost exactly equal to 1/137. (Why 137? That's another question!) Anyway, the Australians got a good fix on the constant's value 2 billion years ago by measuring the composition of the nuclear waste produced by the Olko natural nuclear reactors in Gabon, Africa. It hasn't changed since then. The spectra of distant quasars 7 billion years old also signaled no change. But more-distant and, therefore, supposedly older, gas clouds have suggested that a slightly smaller fine-structure constant held sway then. No known experimental error can account for this difference.
"If confirmed, would Webb's findings eventually be explained by a deeper theory, vindicating physicists' faith in a uniform nature? Or would they mean that we live in a frighteningly arbitrary and variegated cosmos, where huge swathes of space abide by alien principles?"
(Musser, George; "Inconstant Constants," Scientific American, 279:24, November 1998.)
Comment. Even as we write, some distant part of the cosmos may be coming into estrus for life-as-we-do-not-knowit. See SF#34 for "Already, now, we are forgotten on those stellar shores."