Saturday, August 02, 2003

This article from Wired is still chasing itself around my brain. Some of the selective quoting is very misleading or just plain over the top, as you'll know if you're familiar with Steven Gould's actual feelings about religion. Much depends on your understanding of the phrase 'some form of reconciliation'.

Ever so gingerly, science has been backing away from its case-closed attitude toward the transcendent unknown. Conferences that bring together theologians and physicists are hot, recently taking place at Harvard, the Smithsonian, and other big-deal institutions. The American Association for the Advancement of Science now sponsors a "Dialogue on Science, Ethics, and Religion." Science luminaries who in the '70s shrugged at faith as gobbledygook — including E. O. Wilson and the late Stephen Jay Gould and Carl Sagan — have endorsed some form of reconciliation between science and religion.

All the same the article has a couple of interesting ideas at the core of it.

In recent years, researchers have calculated that if a value called omega — the ratio between the average density of the universe and the density that would halt cosmic expansion — had not been within about one-quadrillionth of 1 percent of its actual value immediately after the big bang, the incipient universe would have collapsed back on itself or experienced runaway-relativity effects that would render the fabric of time-space weirdly distorted. Instead, the firmament is geometrically smooth — rather than distorted — in the argot of cosmology. If gravity were only slightly stronger, research shows, stars would flame so fiercely they would burn out in a single year; the universe would be a kingdom of cinders, devoid of life. If gravity were only slightly weaker, stars couldn't form and the cosmos would be a thin, undifferentiated blur. Had the strong force that binds atomic nuclei been slightly weaker, all atoms would disperse into vapor.

Arguments for the Anthropic Principle are a dime a dozen though. The first thing I tried was Googling various key phrases of these arguments on the web, to see if they had been refuted yet. I couldn't come up with an authoritative answer. Finding a scientist in any discipline on the web is e-mail - whether he will answer or even read it is another question. Anyway, different scientists sometimes have different opinions on this. What I really needed was a forum read by many scientists and scientifically knowledgable people of many disciplines, who had the time and inclination to discuss the anthropic principle with laymen who have no formal qualifications whatsoever.

Oddly enough, I knew just where to go.

talk.origins is a usenet newsgroup where creationists and others dispute the theory of evolution, and where these arguments (and others from elsewhere) are disected by interested laypeople. Often the arguments have been refuted in print elsewhere, and the answer can be paraphrased with attribution, but there are some scientists and professors present if anything new needs to be analyzed. There is more about talk.origins here.

My quote of part of Nathan Urban's reply is a link to the complete article.

However, Easterbrook is being very misleading in claiming that this
produces a fine-tuning problem; that was true 25 years ago, but not
today. This fine-tuning problem is known as the "flatness problem":
if the universe deviated from flatness (in the directions of either
positive or negative curvature) by a small amount, a universe like our
own would not be produced. There were a lot of appeals to the
anthropic principle to "explain" the fine-tuning. But since the
advent of inflationary theory, the flatness problem no longer exists.
Inflation explains how the universe can naturally be driven to
Omega->1 during a phase of accelerated "inflationary" expansion, no
matter what the original value of Omega was.

Ironically, Easterbrook mentions Alan Guth, who invented inflation,
without mentioning that Guth's theory killed Easterbrook's fine-tuning
argument about Omega.

On the other hand, Easterbrook's statements about the strength of
gravity and its effects on star formation appear correct; to the best
of my knowledge, we have no universally accepted, natural explanation
for why it takes the value it does.

It's too hasty to conclude that the anthropic principle is the only
explanation, though. For instance, see my own post
,

June 1998 talk.origins post of the month.

His post is very much worth reading, but none of the replies yet offered to the argument are in the strictest sense scientific - which is to say testable. Even if you postulate an infinite number of universes none of them need contain life, just as the infinite set of integers does not contain all real numbers, and some would consider postulating an untestable infinite multiverse as speculative as a creator. Saying that it may be improbably but if it hadn't happened we wouldn't be here to worry about it is interesting, but most scientists confronted with the possibility that they had just observed highly improbably events repeatedly would at least consider alternate possibilities. After thanking him, I did suggest someone should amend the relevant FAQ (written by someone else) for the group, which reads in part:

And the probability that one of a random set of universes is a universe that supports some form of life is a third question. I submit it is this last question that is the important one and that we have no reason to be sure that this probability is small.

I have made some estimates of the probability that a chance distribution of physical constants can produce a universe with properties sufficient that some form of life would have likely had sufficient time to evolve. In this study, I randomly varied the constants of physics (I assume the same laws of physics as exist in our universe, since I know no other) over a range of ten orders of magnitude around their existing values. For each resulting "toy" universe, I computed various quantities such as the size of atoms and the lifetimes of stars. I found that almost all combinations of physical constants lead to universes, albeit strange ones, that would live long enough for some type of complexity to form (Stenger 1995: chapter 8). This is illustrated in figure 1.


As far as I know figure one is accurate, it varies the proton and electron masses and the strengths of the electromagnetic and strong forces but nothing to do with gravity. Seems a little misleading though, assuming Nathan Urban was correct, and if he wasn't it would be the first time I had ever seen something like that go uncorrected on talk.origins.

By now you may be wondering exactly what all of this has to do with the stuff I usually write about on this blog. The ideas I occasionally suggest about global consciousness are very speculative, and no doubt the future will be very different from what anyone alive now imagines, but we don't know the universe so well that we can rule out anything. I think whatever the foundation of consciousness turns out to be, it will be stranger than we can now imagine.

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