The Road Less Traveled

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May 4, 2009 Tags: Design

Today's entry was written by Karl Giberson. You can read more about what we believe here.

The Road Less Traveled

What is the most fascinating question in all of science?

My vote goes to the meaning of the so-called "anthropic principle," and, judging from the traffic to www.biologos.org, the apparent design of the universe intrigues a lot of people. The "anthropic principle" derives from a profound recognition on the part of science in the past few decades that our universe does not appear to have been an accident but rather fine-tuned for life. But what exactly does "fine-tuned" mean?

As science developed in the past few centuries, a most astonishing insight emerged: Everything going on in the universe -- from the swirl of thoughts in your head to the chirping of the bird outside your window to the exploding of a distant star in some far-off galaxy -- is empowered by just four different interactions: the familiar forces of gravity and electricity, including magnetism, and two nuclear forces, one responsible for the fusion reactions in stars like our sun and one that causes radioactivity.

Physicists have studied these four interactions extensively, and they are now well understood. The particular strength of each interaction is perhaps their most interesting feature. You have probably played with magnets and noticed that the magnetic force is much stronger than gravity, which certainly cannot pull apart magnets that are stuck together. In the formulas for these interactions, a number called a "constant of nature" specifies their strength. If you increase the value of this constant, the interaction -- or force --grows larger, and vice versa.

For many years these forces were just numbers, part of the physicists' boring formulas. But in the past few decades all this has changed. Computer modeling makes it possible to see how the values of these numbers affect the structure of the universe, from the formation of galaxies to the structure of DNA.

Consider the strength of gravity. When the Big Bang occurred billions of years ago, the matter in the universe was distributed randomly. There were no stars, planets or galaxies; there were just atoms floating around in the dark void of space. As the universe expanded outward from the Big Bang, gravity pulled ever so gently on the atoms, gathering them into clumps that eventually became stars and galaxies. But gravity had to have just the right force. If the force had been a bit stronger, it would have pulled all the atoms together into one big ball, and the Big Bang -- and our prospects for life -- would have ended quickly in a Big Crunch. If gravity was a bit weaker, the expanding universe would have distributed the atoms so widely they would never have been gathered into stars and galaxies. The strength of gravity has to be exactly right to get stars to form. But what do we mean by "exactly"?

It turns out that if we change gravity by even a tiny fraction of a percent -- enough that would make you 1 billionth of a gram heavier or lighter -- the universe changes so much that stars, galaxies and planets do not exist. And, of course, without planets there would be no life.

The other constants of nature possess this same feature. Change any of them and the universe -- like Robert Frost's traveler -- moves along a very different path. Remarkably, every one of these different paths leads to a universe without life in it. Our universe is friendly to life but only because the last 15 billion years have unfolded in a particular way that led to a habitable planet with liquid water and rich chemistry.

People who have reflected on this have many different reactions. Some speculate there must be an infinity of different universes with every imaginable combination of properties; we just lucked out to be in a universe capable of having people in it. My favorite response to the fine-tuning of the universe, though, is that of Freeman Dyson, former physics professor at the Institute for Advanced Study at Princeton University and one of the most brilliant and interesting astrophysicists living today. "The more I examine the universe and the details of its architecture, the more evidence I find that the universe in some sense must have known we were coming,"writes Dyson in his 1979 autobiography, Disturbing the Universe.

I asked Dyson if 30 years later, he still feels the same way about his oft-quoted phrase.

"Yes," he said, "though I hate the word `anthropic' because that refers exclusively to humans." The Greek anthropos means a man or a human. "What it says is that the universe has to be built in such a way that intelligent creatures can ask questions about it. It doesn't mean the universe was designed for humans. That's not what I intended to say. What it means is that the universe seems to be constructed in a way that it is hospitable to life and intelligence. I still think that's true."

(The full text of this interview is available at www.biologos.org)

The fine-tuning of the universe is a perfect example of the BioLogos perspective: God is working continually within, through and behind the unfolding patterns of nature to bring about God's intentions and purposes. Such a claim goes beyond science. Even Dyson, with characteristic modesty, is reluctant to claim too much. But reality is more than just science, and as Christians, we can celebrate in worship the marvelous character of the world that science has unfolded for us.


Karl Giberson directs the new science & religion writing program at Gordon College in Boston. He has published more than 100 articles, reviews and essays for Web sites and journals including Salon.com, Books & Culture, and the Huffington Post. He has written seven books, including Saving Darwin, The Language of Science & Faith, and The Anointed: Evangelical Truth in a Secular Age.


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Sean - #10798

April 22nd 2010

How would one answer the claim that the universe does NOT evidently appear to be hospitible to life?  I have heard the claim that large portions of the Earth itself, much less else where in our own solar system (and even far less in our galaxy and so on), is not hospitable to life.  With this evidence of the universe on a whole (as opposed to evidence of life on earth) taken into account, by what standards does one judge that the universe as a whole is hospitable to life?

If one concludes that the universe as a whole is NOT hospitable to life, then what is left of the anthropic principle argument?


Nicolaus - #14021

May 18th 2010

Sean,
What is meant by hospitable is that life is able to exist at all in the universe. The changing of the physical constants would result in a universe unable to support life anywhere. The fact that life can and does exist somewhere is what is meant by the universe being hospitable. And so hospitable to life simply means that life is possible with the physical constants the way they are whereas any change, even the slightest change, would result in a universe incapable of supporting stars and complex atoms let alone the eventual evolution of life.


Sean - #14968

May 25th 2010

Nicolaus,

Thanks for providing this explanation as to what is meant when the statement “the universe is hospitable to life” is made.

I understand your explanation, however I may have misworded the focus of my question.  I am not so much concerned with what the definition of what is meant by “hospitable to life” as the focus on life when considering the anthropic principal, let me explain by way of analysis:  To my understanding, dark matter is the most abundant form of matter in the universe.  Given that (to my understanding) dark matter has yet to be fully understood, I will fall back on the second most abundant form of matter in the universe, plasma, the coagulation of proportionally ionized gas particles typically found in formations like stars.

With a quick Google search, one can learn that 99.9% of all observable matter is in the form of plasma, that an estimated 4% of the universe’s energy is in the form of observable matter, and that the estimated mass of the observable universe (stress on “observable”) is 1.59*10^55 kg.  The mass of the earth, in comparison, is a mere 5.98*10^24 kg.


Sean - #14969

May 25th 2010

Since we know that 99.9% of observable matter is in the form of plasma, what is the percent of matter in the form of life?  For the sake of argument, I’ll give you that THE WHOLE EARTH is alive (therefore the earth’s full mass will be used in my calculation, even though in a comparitively small amount of matter on earth is in the form of life).  We then calculate the percentage of matter in the form of life in the observable universe as:

(5.98*10^24)/(.99*(.04 * (1.59*10^55)))*100 = 9.5 * 10^-28 %

Again, I stress, why is the focus of the anthropic principal on life (apart from the obviouus use of the word “anthropic”)?  Here we calculate that nearly 99.9% of the observable matter in the universe is comprised of plasma, while just a little more than one tenth of one billionth of one billionth of one billionth of the observiable matter in the universe is comprised of life!!!


Sean - #14970

May 25th 2010

It seems obvious to me that if we are to be focusing our energy in attributing some “purpose” to the universe, it should most certainly be focused on how a universe tweeked just so one way or the other would provide for the possibility of plasma in the universe, as certainly life is a quite miniscule aspect of the universe when taken on the whole.

Nicolaus, does this clarify my original question better?


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