June 15, 2006

The Heavens Declare His Glory (part 2)

Location, Location, Location
(Part 2 in a 4 part series)

Let's get back to this idea, premised in part 1, that we are not so special in God's mind because we are only an average world flung off in a remote corner of the universe.

If we were really important, where would God place us? Perhaps right in the middle of the action, right at the center of some glamorous cosmic construction? (Of course, this all assumes that it is not God's intention to humble us, but I don't need to go down that road to make my points.) Let's walk through the universe and its possibilities.

Just what are the grandest structures in the universe in which God might place us? Well, galaxies are where the action is, but even these come in clusters. Maybe God should have placed us in one of those super clusters (like the nearby Perseus Cluster) containing thousands of galaxies. The bad thing about that is when you've got so many nearby massive neighbors, collisions and gravitational disturbances can result. And if one of those neighbors is a high-energy emitter, which is increasingly likely the more that you have, then it can be bad news for anything unshielded nearby.

Okay, let's start with a safer little cluster of galaxies, like our own Local Group by the way. But at least God could put us in a nice, big, impressive galaxy. The biggest ones by far are the elliptical galaxies — giant ellipsoid (egg-like) masses of stars. But the problem with these galaxies is that they are generally the product of galactic collisions, and are made up primarily of older red giant stars, which are not good hosts for planets (more on that later). They have little free gas, dust, and heavy elements for planet making. Their stars are densely packed, which would be devastating to the orbits of any existing planets (this problem will be a recurring theme). And, so far as we know, they always contain one or more giant black holes at their core, which spray out some rather nasty particles and radiation whenever matter comes within proximity. All in all, an ill-suited place to be.

Okay then, how about a nice big spiral galaxy? These are actually quite lovely and diverse places. While not as massive and star-packed as the giant ellipticals, they have a similarly dense nucleus and spiral arms. What about right in the center of one of these cosmic pinwheels? Well, unfortunately we've got similar gravitational and radiation problems as with the ellipticals in that large spiral galaxies tend to also contain super-massive black holes. Even the arms of the spirals are pretty dense, which increases the likelihood of gravitational interference with other stars and escalates the chances of crossing paths with a supernova or other nasty neighbors. And the problems are much the same for any of the massive star clusters that can be found throughout most galaxies.

Another bad thing about densely star-packed areas is that even if you could manage to survive in such a region you wouldn't have the pleasure of seeing outside of the forest for all the trees (so to speak). That is to say, you wouldn't have a night sky, and you'd never witness the cosmos in certain electromagnetic wavelengths due to all the interference. In the spiral arms you'd have even more problems of this nature, since this is where you find most of the free-floating dust and gasses. While it might make for some interesting local effects, given the right illumination, in this region it's possible that you might not even be able to observe many of your stellar neighbors due to the obstruction.

So, just where is a good place to be? Well, as it turns out, spiral galaxies are not all bad. There are certain regions within them that are fairly cozy, and we don't have to go to the lonely fringe of the galaxy to find them. In fact, if God preferred the formation of our sun and planets from materials at hand, they would most readily be found nearer the central area. This is because you need a certain abundance of gases and stars to begin with, which are more sparse in the periphery, in order to facilitate the various rounds of star birth and death that manufacture the heavier elements. You see, the original material of the universe was primarily hydrogen, and (short of divine intervention) the heavier elements are only produced in the fusion engines we call stars and during their explosive death throws (i.e., novas and supernovas). Heavy elements — carbon, oxygen, silicon, iron, etc. — are important for planet forming and for imparting certain desirable characteristics to stars (and, or course, for life). It can take time to build up and release a significant amount of such materials, and this tends to happen in the galaxy from the inside out. All this boils down to a galactic habitable zone that falls somewhere between the inner core and the outer edge, yet not directly within the densely packed arms.

The bottom line is that the less populous space between the arms of the spirals is a perfect location for life, and, as an added bonus, would let the inhabitants have a clear view of both the nearby arm(s) of their own galaxy and an unobstructed view outside of the galaxy. And if that world were in a nice circular orbit near the corotation radius of the galaxy, then it would seldom risk crossing through the spiral arms. You'd also want an orbit that stayed well within the plane of the galaxy so as not to peek above or below the shielding dust of the inner rings and be exposed to the volatile output of the galactic core. Our own solar system happens to be situated in just such a place.

At this point it is worth mentioning that most of the stars in the universe happen to be locked up in hostile environments like elliptical galaxies, star clusters, galactic cores, and spiral arms. By comparison, the number of stars that are in the right kinds of positions within the right kinds of galaxies is miniscule. And even when we begin to look at stars that might be in prime real estate we find that very few of these make a friendly host.

But before I begin down the path of illustrating the kind of local variables required for life (e.g., stars and planets), let me just emphasize the fact that our world is in a very good place, being both safe and advantageous for viewing the action in the universe at large. Can the charge that we are no place special be sustained? Only if one could say that a babe cradled in his mother's arms looking safely through the window at his world is no place special. And even if there might be other mothers and other arms, it does not make his any less good.

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20 Comments:

At 6/16/2006 3:39 PM, Blogger Sam Harper said...

Those are some cool pictures.

Personally, I think the whole issue of whether we're in a remote corner of the universe or not is silly. Every corner of the universe is remote! The same thing could be said no matter where we were.

 
At 6/16/2006 4:00 PM, Blogger Paul said...

Yeah, I love astronomy pics. I whiled away a lot of time looking at pictures and articles instead of working on these posts. This is one of my favorite areas of science, and I should probably do some stuff on the Cosmological Argument and Anthropic Principle because of that. These are topics that really hooked me on apologetics in the first place (on Christianity even).

You're right that this is a not really a weighty argument to be responding to, and I've worried that I'm really blathering on to no effect. That's why I'm trying to redeem it by pointing out the "just right" aspect of the whole thing. The stellar and planetary requirements compound that problem greatly, which I hope to address next. I'm kind of anxious to move on though; I've got another topic that's eating a hole in my pocket, so to speak.

 
At 6/16/2006 10:48 PM, Blogger Sam Harper said...

That's funny. It sounds like you're saying you're anxious to do some stuff on the cosmological argument just so you can post really cool pictures.

It guess it all depends on what exactly the objection is. I think you've put it in the best light possible before responding to it.

 
At 6/18/2006 1:51 PM, Blogger JELyon said...

Just, you know, 'cause:

http://www.pbs.org/lifebeyondearth/listening/drake.htm

Are there civilizations out there listening? We don't yet know the answer, but Dr. Frank Drake, president of the SETI Institute, came up with an equation that allows us to make an estimate by muliplying seven quantities related to the prevalence of life. Since its introduction in 1961, this tool has come to be known as the Drake Equation.

Use the Drake Equation to make your own estimate of the number of communicative civilizations in the Milky Way

 
At 6/18/2006 4:43 PM, Blogger Sam Harper said...

If you think about it, even if there is more life in the Milky Way, we've still got a very small chance of knowing about it. The Milky Way is 100,000 light years across. We've only had radio technology for about a hundred years. Even if there were teams of living beings as intelligent and advanced as us, we could only know it if they live within 100 light years of us, which isn't very much space in the Milky Way. The only way we could detect intelligent life any farther out than that is if it were more advanced than us. And the only way we could cover the whole Milky Way is if other forms of life were thousands of years head of us in technology.

 
At 6/20/2006 1:07 PM, Blogger Paul said...

I find the Drake Equation to be a failure for several reasons.

1) It leaves out many important factors for fine-tuning the criteria. For example, in the very first step it completely misses the problems associated with the location of stars in the galaxy even if they would otherwise be "suitable" to support life. This first variable also does not take into consideration the fact that there is a window of time in which the galaxy is habitable, e.g., early on the galaxy is a rather volatile place, and you also need several rounds of star birth and death in order to build up the materials you would want for habitable planet formation.

2) It requires one to make massive, blind assumptions for most of the variables. For instance, we are only beginning to learn about planets orbiting other stars. How are we at this stage to determine values for Fp and Ne (i.e., stars with planets that are suitable for life)?

3) Because the formula is not precise and relies on assumptions, it only ends up affirming one's original presupposition. If you are optimistic about life on other planets to begin with, you will be optimistic in the numbers you assign to each variable.

4) It assumes something that I do not grant, and which has not yet been proved out: that life can form by mere chance, and even if it could do so, that it could evolve into an intelligent form. So, if I do not accept these premises, I will put a zero in either Fl or Fi and the resulting calculations will give "zero civilizations." This formula is meaningful only to committed materialists.

5) Even presupposing materialism, and supplying reasonably optimistic values, I get a number far less than zero. I think SETI is wasting its time by any reckoning.

 
At 6/23/2006 6:37 PM, Blogger Psiomniac said...

If you got a number less than zero I think you need to redo the math.
I think the problem is as you say the parameters for the variables are too wide. However I think you are too pessimistic, which ties in with your earlier point about the Drake equation confirming optimism or pessimism. The trouble is we simply don't know whether things have to be as finely tuned as you say, this is speculation as well. Even if it were so spectacularly unlikey (as you know I regard abiogenesis as credible) as to only have happened once in the entire universe (unlikely I think) then we are it, and you wouldn't then want to commit the lottery fallacy would you?

 
At 6/24/2006 2:54 PM, Blogger Paul said...

You're right, I didn't mean less than zero, I meant fractional.

How can you say I'm being too pessimistic if "we simply don't know" about the fine-tuning? I think I'm being quite reasonable given where the evidence has been leading. And I'm not just talking about "evidence" as offered to me by biases Christian interpretation; I'm talking about mainstream, secular, peer-reviewed findings. The problem is that the constraints required for life, and the apparent fine-tuning, is not decreasing with our increase of knowledge; the observation of fine-tuning is on the rise. This is one of the primary reasons for the introduction of the multi-verse theory, which posits that life is not so remarkable if we just happen to be the lucky lottery winners in an infinity of universes. But that's another topic.

And I do not think that the lottery fallacy applies here. In the lottery, the chances are very good that someone will win, since millions of people are in the game. What I am suggesting here, in a roundabout way (which I'll add to in the next post), is that there just aren't that many possible players in this lottery. I'm sure that you would concede that if just one (or 10, or 1000) people play the lottery, then it is certainly a remarkable thing if there is a winner. Beyond that, I think the odds of abiogenesis (a lottery win) are so fantastically great, that even if every solar system were like our own, it would be incredible for any to produce life by sheer chance.

I know that you are very optimistic about abiogenesis, but if you dig deeply into any of those "promising" areas of investigation you will see the dead-ends. I know that imagination drives good scientific hypothesis, but imagination cannot eternally serve as a surrogate support for a materialistic commitment. That kind of faith is invincible.

 
At 6/24/2006 6:59 PM, Blogger Psiomniac said...

The reason I can say you are being too pessimistic is that because we don't know about the fine tuning and the possible robust nature of life. You can still get wildy divergent predictions based on the secular evidence that you mention.
I think the lottery fallacy does apply for two reasons. The first is that you have not done the requisite number crunching on mid range figures for the number of likely habitable planets. I did this the other day using a Drake calculation website using conservative estimates and got a figure of 1000 for this galaxy. The second is that your calculations and evaluation of the abiogenesis question proceed from false premises. I have not seen the dead ends that you have because I do not assume that the forerunner of today's complex co-evolved molecular machinery is of the same form as that of today. For more on this see here

 
At 6/25/2006 12:24 PM, Blogger Sam Harper said...

I think it's kind of depressing that even if there is life somewhere else in the universe, we will probably never know it. The universe is just too big.

Even if there is life in other parts of our own galaxy, what are the chances that it's intelligent life? I mean the kind of intelligence capable of written language, the ability to invent radios and things like that. Of the millions (billions?) of species on our own planet, there's only one capable of written language and the ability to invent radios. You have to admit that we're rare kind of species even on our own planet. Before Seti could ever discover life, there would have to be other intelligent life like us. If life of any kind is rare, think how much more rare intelligent life is!

 
At 6/25/2006 6:16 PM, Blogger Paul said...

That's the thesis of the book, Rare Earth. It's not only that intelligence is unique to life, but that the requirements for supporting us complex and sensitive organisms are so much greater than for microbial life.

 
At 6/27/2006 1:06 PM, Blogger Paul said...

They might say that intelligence is inevitable, but that presumes that as the penultimate product of evolution. I think algae, cockroaches, and alligators are counter-examples of fitness for survival. An organism doesn't have to be smart to breed and stay alive, which is all that evolution demands. What's a mystery to me is why evolution would drive organisms upward toward more complex, sensitive systems with more failure points, rather than just settling into the simplest functional groove. And I'd think they'd be forced into it by need of surviving the millions of detrimental mutations for any single beneficial one.

 
At 6/27/2006 4:38 PM, Blogger Psiomniac said...

Jeff,
I do not think that Paul is committing the lottery fallacy, nor did I say he was. I raised it as a kind of rhetorical 'given'. It is more that Paul's figures proceed from a sample size of 1, namely us and so just as he says I am not entitled to be optimistic by the same token I am saying he is not entitled to be what I regard as pessimistic.

Paul,
I do not think that intelligent life is inevitable given abiogenesis and evolution but looking at the situation before us on Earth, it is clear to those who accept evolution that our kind of intelligence fills a niche that evolution exploited in our case. It may be the case that the mean timespan for evolution to do this is 5 billion years. Or it might be 8 billion and we are 'early' or 3 billion and we are 'late'. We simply do not know at this stage.
Your final point about why evolution drives some organisms toward complexity is answered (in a simplified way) by the fact that small relatively 'cheap' increases in complexity allow you to outcompete your simpler cousin species. From then on, it is like an arms race.

 
At 6/28/2006 11:49 AM, Blogger Sam Harper said...

I'm ready for part III. How long are you going to keep us in suspense, Paul?

 
At 6/28/2006 12:44 PM, Blogger Paul said...

Sorry Sam, I'm having a hard time with time. I also keep redoing my text because I can't figure out a good way to take the next step that says enough in a meaningful and technically accurate way yet doesn't go on and on. There's so much to say about the requirements for life. Seems like every week we learn more details about the requirements for life and the unique characteristics of our home. I have a compulsion to be exhaustive but not the time, but the point here is only driven home if you see the many factors involved and how they play out statistically.

 
At 6/28/2006 1:07 PM, Blogger Paul said...

Psio,

I know how the just-so stories go: filling niches and out-competing. My challenge regards why complexity has to be that mechanism of improvement. To out-compete, you don't necessarily need to be more complex. And being more complex comes with its own liabilities. As I said, more things to potentially go wrong. More places where nasty mutations can get a foothold, especially since there becomes more DNA to maintain and copy.

Another odd thing for evolutionary theory: As you say, the upward progression is for the sake of competition and survival. But for many of the species that exist today, evolutionists seem to be willing to point to other living species that are the simpler, earlier predecessors of those species. This means that their earlier forms continued to be successful and unchanged over time. This negates the idea that evolution (in at least these cases) was merely a need-based thing, i.e., change or die.

 
At 6/28/2006 6:13 PM, Blogger Psiomniac said...

Paul,

You said:
"I know how the just-so stories go"
But the real question is do you know how the branches of science that deal with evolution go. I suspect not much if you are comparing them with just so stories.
"My challenge regards why complexity has to be that mechanism of improvement. To out-compete, you don't necessarily need to be more complex."
This view has the wrong emphasis I think. All that is required is that complexity is an avenue that works.
"And being more complex comes with its own liabilities. As I said, more things to potentially go wrong. More places where nasty mutations can get a foothold, especially since there becomes more DNA to maintain and copy."
But with more DNA comes more error correction mechanisms. Again all that is required is that statistically there is a net benefit in terms of procreation. I don't see profound difficulties here.
"Another odd thing for evolutionary theory: As you say, the upward progression is for the sake of competition and survival. But for many of the species that exist today, evolutionists seem to be willing to point to other living species that are the simpler, earlier predecessors of those species. This means that their earlier forms continued to be successful and unchanged over time. This negates the idea that evolution (in at least these cases) was merely a need-based thing, i.e., change or die. "
I do not think this is true. We may find species that are like the ancestors of a given species in some ways, or occupy a niche that was once the domain of a now more complex species. This is not unexpected or problematic. If species are in an arms race against each other and some die out, at some time in the process they will no longer be in direct competition with species that occupy the level they used to be at because they have vacated it. So it is not a contradiction that the role gets filled by new species.

 
At 6/30/2006 12:46 PM, Blogger Psiomniac said...

Jeff,
There are a lot of things I could say in response to your last post but for now just a few quick points:

I have read many books about evolution written by respected scientists in the field. In none of them did I find any reference to any directive force whatsoever.

The increase in complexity of organisms definitely does not contravene the second law of thermodynamics. This is because we have a large fusion reactor nearby called the sun pumping energy into the system.

Finally I think your point about adding information to the genome is just factually incorrect. Many of the known ways that mutations occur are capable of adding information. For example random insertion and repetition of nucleotides can happen. The vast majority of the time the information is garbage and is harmful to the organism. But not always, and that is all that is required for this aspect of evolutionary theory to work.

 
At 7/03/2006 8:50 AM, Blogger Psiomniac said...

"I think SETI is wasting its time by any reckoning."

"The surest sign that intelligent life exists elsewhere in the universe is that it has never tried to contact us"--Bill Watterson, Calvin and Hobbes.

Lol. Couldn't resist that one.

 
At 7/04/2006 6:12 PM, Blogger Psiomniac said...

Jeff,

For a more detailed look at the other side of the argument about mutations adding information go here

 

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