Posted on 10/27/2003 7:38:33 PM PST by Brilliant
CLEVELAND — Cosmology used to be a heartless science, all about dark matter lost in mind-bending abysses and exploding stars. But whenever physicists and astronomers gather, the subject that roils lunch, coffee breaks or renegade cigarette breaks tends to be not dark matter or the fate of the universe. Rather it is about the role and meaning of life in the cosmos.
Cosmologists held an unusual debate on the question during a recent conference, "The Future of Cosmology," at Case Western Reserve University here.
According to a controversial notion known as the anthropic principle, certain otherwise baffling features of the universe can only be understood by including ourselves in the equation. The universe must be suitable for life, otherwise we would not be here to wonder about it.
The features in question are mysterious numbers in the equations of physics and cosmology, denoting, say, the amount of matter in the universe or the number of dimensions, which don't seem predictable by any known theory — yet. They are like the knobs on God's control console, and they seem almost miraculously tuned to allow life.
A slight tweak one way or another from the present settings could cause all stars to collapse into black holes or atoms to evaporate, negating the possibility of biology.
If there were only one universe, theorists would have their hands full trying to explain why it is such a lucky one.
But supporters of the anthropic principle argue that there could be zillions of possible universes, many different possible settings ruled by chance. Their view has been bolstered in recent years by a theory of the Big Bang, known as inflation, which implies that our universe is only one bubble in an endless chain of them, and by string theory — the so-called theory of everything — whose equations seem to have an almost uncountable number of solutions, each representing a different possible universe.
Only a few of these will be conducive to life, the anthropic argument goes, but it is no more surprise to find ourselves in one of them than it is to find ourselves on the moist warm Earth rather than on Pluto.
In short we live where we can live, but those can be fighting words.
Scientists agree that the name "anthropic principle," is pretentious, but that's all they agree on. Some of them regard the idea as more philosophy than science. Others regard it as a betrayal of the Einsteinian dream of predicting everything about the universe.
Dr. David Gross regards it as a virus. "Once you get the bug you can't get rid of it," he complained at the conference.
Dr. Gross, director of the Kavli Institute for Theoretical Physics in Santa Barbara, Calif., had agreed to lead a panel discussion on the notorious principle. Often found puffing on a cigar, he is not known to be shy about expressing his opinion.
"I was chosen because I hate the anthropic principle," he said.
But playing a central role in defending the need for what he called "anthropic reasoning" was Dr. Steven Weinberg, a Nobel laureate from the University of Texas. Like Dr. Gross, Dr. Weinberg is a particle physicist who is known for being a hard-core reductionist in his approach to science, but he evinces a gloomy streak in his writings and his talks. He is still famous for writing in his 1977 book, "The First Three Minutes," "The more the universe seems comprehensible, the more it also seems pointless."
Dr. Weinberg is among the most prominent of theorists who have reluctantly accepted, at least provisionally, the anthropic principle as a kind of tragic necessity in order to explain the gnarliest knob of all.
Called the cosmological constant, it is a number that measures the amount of cosmic repulsion caused by the energy in empty space. That empty space should be boiling with such energy is predicted by quantum theory, and astronomers in the last few years have discovered that some cosmic repulsion seems to be accelerating the expansion of the universe. But theoretical attempts to calculate this constant, also known as lambda, result in numbers 1060 times as high as those astronomers have measured.
So despairing are physicists of understanding the cosmological constant that Dr. Weinberg joked earlier at the meeting that he would no longer read papers about it.
Back in 1989, before any cosmological constant had been discovered, Dr. Weinberg used the anthropic principle to set limits on the value of the constant. Suppose instead of being fixed by theory, it was random from universe to universe. In that case the value of the cosmological constant in our universe may just be an "environmental effect," he explained, and we shouldn't expect to be able to predict it exactly any more than you can calculate how much rain will fall in Seattle this Christmas.
In his paper, Dr. Weinberg argued that lambda in our universe could not be too big or the repulsive force would have prevented the formation of galaxies, stars and us. Since we are here, the constant should be small.
The recently discovered "dark energy" causing the cosmic acceleration fits comfortably inside Dr. Weinberg's limits, vindicating in a way the anthropic approach.
In his talk, Dr. Weinberg described the anthropic principle as "the sort of historical realization scientists have been forced to make from time to time."
"Our hope was to explain everything," he said. "Part of progress is we learn what we can explain on fundamental grounds and what we cannot."
Other panelists, including Dr. Alex Vilenkin, a physicist from Tufts University, suggested that the anthropic reasoning was a logical attempt to apply probabilities to cosmology, using all the data, including the fact of our own existence. Dr. John Peacock, a cosmologist at the University of Edinburgh, argued that the anthropic principle was not a retreat from physics, but an advance. The existence of an ensemble of universes with different properties, he explained, implies a mechanism to produce variation, a kind of cosmic genetic code, the way that evolution implies the existence of genes.
"You gain new physics," Dr. Peacock said.
But when his own turn came, Dr. Gross questioned whether the rules of the anthropic game were precise enough. What were the parameters that could vary from universe to universe? How many could vary at once? What was the probability distribution of their values, and what was necessary for "life"?
Anthropic calculations are inherently vague and imprecise, he said. As a result, the principle could not be disproved. But he was only getting warmed up. His real objection, he said, was "totally emotional."
Ascribing the parameters of physics to mere chance or vagaries of cosmic weather is defeatist, discouraging people from undertaking the difficult calculations that would actually explain why things are they way they are. Moreover, it is also dangerous, he declared to ringing applause.
"It smells of religion and intelligent design," he said, referring to a variety of creationism that argues that the universe is too complex to have evolved by chance.
Dr. Lawrence Krauss, the astrophysicist from Case Western who had organized the conference and recruited the panel, characterized the anthropic principle as "a way of killing time" when physicists didn't have a better idea. Dr. Krauss, who has battled creationists over biology instruction in the public schools in Ohio, said he had encountered anthropic arguments as an argument for fine-tuning, the idea that God had fixed the universe just for us.
Dr. Weinberg replied that the anthropic principle was not really a part of science, but rather "a guess about the future shape of science."
"If we didn't have things in our universe that seem peculiar, like the value of the cosmological constant, we wouldn't worry about it," he said.
Dr. Weinberg compared the situation to a person who is dealt a royal flush in a poker tournament. It may be chance, he said, but there is another explanation: "Namely, is the organizer of the tournament our friend?"
"But that leads to the argument about religion," he said to much laughter.
In fact, Dr. Weinberg said, the anthropic principle was "a nice nontheistic explanation of why things are as nice as they are."
By then the audience was squirming to get in on the action. Hands were waving as Dr. Gross called the session to an end. "Clearly there is a diversity of opinion," he intoned. "Some people find the small value of cosmological constant so bizarre that only the anthropic principle will pick it out."
Nobody who adheres to the anthropic principle, he said, would hold on if there were "an honest old-fashioned calculation," that explained the cosmological constant.
Given the floor for the last word, Dr. Weinberg agreed that it was too soon to give up hope for such a breakthrough. "I'm prepared to go on hoping that one will be found," he said. "But after the passage of time one begins to entertain other possibilities, and the anthropic explanation is another possibility."
Applying that mode of reasoning, he said, could help make the cosmological constant less peculiar,
"But we don't know if that's the help that we really deserve to get," he concluded.
And it was time for lunch.
Dr. Gross reported later that younger physicists had thanked him for his stand.
Dr. Weinberg said the panel had generated more fuss than the subject deserved.
"Those who favor taking the anthropic principle seriously don't really like it," he said, "and those who argue against it recognize that it may be unavoidable."
In general, I think we all agree that God is transcendent -- i.e., beyond the material universe.
Given that, the discussion becomes simpler.
GO65 (post 30) has led us to a "difficult book to read" that supports the existence of God. And I presume that the book makes a case for a transcendent God -- a very difficult subject indeed, for fallible beings.
Georgia Yankee (post 52) asks "What do you mean by reality?" while providing four dictionary definitions for reality in which 3 of 4 use the words "actual" or "actuality," with the 4th using the terms "objectively" and "fact." Those are good definitions for reality, but please note that they have no reference to the terms mystical or transcendental.
nmh (post 67) refers to "the Alpha and the Omega" and asks: "Must He be limited by your intellect?" In answer, I'd just like to observe that it is we humans that have limited intellects ... along with substantial ability to combine reason with perception to know things.
Forgiven_Sinner (post 148) asks: "Please explain why I cannot say: 1. Realty is what exists. 2. Reality consists of what is created, plus ... 3. that which is not created, God." ... To which I'd say Forgiven-Sinner cannot say that because definition 1 contradicts the sum total of definitions 2 and 3. In fact, I'd add that Forgiven_Sinner's definitions contain the same contradiction I used in post 24 for an opposite purpose.
I'll end with one comment.
It's nice to think that humans are Godlike, but that is not realistic.
If that's the case, why should we believe anything about which we have no firsthand experience? Most of us have not been to space, so how do we know the world is round? How do we know the moon is dry and rocky? You take these matters as truth as a matter of faith.
Lastly, of course you will feel more at ease with those who share your humanistic worldview than those who believe the Bible. Darkness and light cannot have fellowship.
No, I don't like what you're saying because I'm tired of Christians proclaiming their moral superiority, for which there is precious little evidence.
Lastly, of course you will feel more at ease with those who share your humanistic worldview than those who believe the Bible. Darkness and light cannot have fellowship.
That's a depressing thought, but maybe you're right. Enjoy your darkness. I'm a Bright
BTW this does NOT apply to evolution, which is taught as fact even though it has never been obeserved, measured, or repeated, despite numerous attempts to force mutations in fruitfly populations and create life in a bowl. Evolution itself as an idea has "evolved" from slow and gradual changes, to rapid ones - which would be nearly impossible to prove, as the changes are rare and rapid. Lamarckianism and recapitulation theories have come and gone. And the strangest thing, to me, is the fact that paleontology serves as the date measuring rod for geological forms, even though the ages of the fossils are at the very best, a guess, based on the unprovable assumption of evolution. Carbon dating only proves useful back to ten-thousand years.
Do you admit that there is great cause for doubt regarding evolutionary theory? It's as though they start with the a priori assumption that "the Bible can't be true because it's a fairy tale", and then go on to attempt to explain reality otherwise, effectively writing a tale of their own.
You claimed people in St. Louis were nicer than people at Berkeley, and it's all on account for the former being Christians and the latter evolutionists. Want to back away from that?
Why shouldn't Christians be able to bring up their children without Big Brother trying to rebut their religious upbringing by teaching evolution in the schools? Why is evolution so crucial to their education that teaching it in public schools is more important than religious freedom?
We teach science in the schools. We aren't going to edit what we teach because a sectarian group's peculiar beliefs contradict a large body of scientific evidence.
Would that ignorance include accepting as fact that which has never been proven, or observed, or measured? How is this any less closeminded than believing the Genesis account? Don't just resort to insult and mockery (as your type seem wont to do), I would like to see a sensible answer.
Dakmar...
I took a few minutes to decipher that post, and I must say I agree with a lot of what you said.
fC...
These were the Classical liberals...founding fathers-PRINCIPLES---stable/SANE scientific reality/society---industrial progress...moral/social character-values(private/personal) GROWTH(limited NON-intrusive PC Govt/religion---schools)!
Dakmar...
Where you and I diverge is on the Evolution/Communism thing. You seem to view Darwin and evolution as the beginning of the end for enlighted, moral civilization, while I think Marx, class struggle, and the "dictatorship of the proletariat" are the true dangers.
God bless you, I think we both have a common enemy in the BRAVE-NWO.
452 posted on 9/7/02 8:54 PM Pacific by Dakmar
A lie. See post 199.
And the strangest thing, to me, is the fact that paleontology serves as the date measuring rod for geological forms, even though the ages of the fossils are at the very best, a guess, based on the unprovable assumption of evolution.
Another lie. Large numbers of fossils have been dated radiometrically.
Carbon dating only proves useful back to ten-thousand years.
More like 50,000 years; but we have U/Th dating, K/Ar dating, Ar/Ar dating, Rb/Sr dating....
Do you admit that there is great cause for doubt regarding evolutionary theory? I
On the contrary, it's as solid as the second law of thermodynamics and the periodic table.
It's as though they start with the a priori assumption that "the Bible can't be true because it's a fairy tale", and then go on to attempt to explain reality otherwise, effectively writing a tale of their own.
I do science. I'm not interested in the 3000 year old cosmological theories of a small tribe in the middle-east, any more than I'm interested in the hundreds of other alternative creation myths.
Most of what you will get in biology classes is based on the unprovable assumption of evolution. You have not answered this but only begged the question - pointing to something which assumes evolution without offering real, scietific support for the theory itself. Let me answer for you: You will find NONE in the schools, as there is none to be found.
Evolution is being taught in our schools not because it's an important part of the ciricullum, but rather because the leftists want to mix it up with the fundamentalists and they know that is their hot button.
I disagree. I'm teaching a freshman course in the Chemical Basis of Evolution this fall, and I can tell you the students knew essentially nothing about it coming in (and precious little biology of any kind).
Physics would be a much more important thing to learn.
Biotechnology and genomics are growing by leaps and bounds. Studnets need to know fundamental genetics, for example.
Boy, talk about straw men... I never said that. I made reference to percentages of the respective populations. St. Louis is home to many Christian denominations, including Lutherans, Church of Christ, Catholics, and Pentecostals - not all of whose theologies I agree with but all of whom are nonetheless theists. And strangers, as a general rule, are friendler in this part of Missouri than the average stranger on the streets of Berkely... or San Jose. Incidently, Missouri is also a far more conservative state than California. I think there's a link, and I have a wider frame of reference than just these two locales to support this.
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