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[Al Degutis]

A team of NASA exobiology researchers revealed today organic chemicals that play a crucial role in the chemistry of life are common in space.

"Our work shows a class of compounds that is critical to biochemistry is prevalent throughout the universe," said Douglas Hudgins, an astronomer at NASA's Ames Research Center, Moffett Field, Calif. He is principal author of a study detailing the team's findings that appears in the Oct. 10 issue of the Astrophysical Journal.
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Full Story: www.physorg.com/news7159.html

[Maddad]

Thanks for the article, Al Degutis.

[Centaur]

No surprise. Naturally life is composed of plentiful materials that are made from common elements that are readily available and easily form compounds. That's the simplest and expected route, as Occam's Razor might determine. Nevertheless, the possibility remains that the life producing process (particularly regarding intelligent species) faced so many difficult hurdles that it happened only once.

[Maddad]

I have talked extensively by email with a professor on the genesis of life. We kept returning to needing life to start life. We were dealing with numbers that had billions of zeros in them. Felt like we were making progress when we reduced the chance against life to only a few hundred thousand zeros.

[Chicago Astronomer - Astro Joe]

Life from life...but everything has a start...somewhere. Or is it a concept that our feeble minds cannot yet get a grasp on?

I wonder when Intelligent life will be discovered on planet Earth...

[Centaur]

admin said:

Life from life...but everything has a start...somewhere.

Yes, some are perplexed by the chicken/egg paradox, when of course chickens evolved from a line of ancestral forms going back at least as far as bacteria. And it was a string of chemical interactions that led to the first bacterium. We don't live in a steady state universe of infinite age with all processes running in circles.

A crystal will form and grow as an organized structure requiring only the seed of a single molecule. Is a crystal life? DNA and even RNA are far more complex than a crystal. The precursors of those self-replicating molecules might have been much simpler, but still may have required great luck to have formed and then produce a surviving line of descendents with the ability to evolve. Nevertheless, it happened at least once despite the odds. But once is all that was required for us to be able to hold this discussion. The probability against life getting started may indeed be so astronomical that it did not happen twice. And if it had happened another time before it did on Earth, that first development may have prevented or halted the second one. Some may consider that terrestrial life began on another planet. Though possible, it adds an unnecessary complexity, especially considering the amazingly benign conditions that developed on Earth.

Those who enjoy discussing similar topics with other bright individuals might consider visiting these two sites:
forums.randi.org/forumindex.php
www.skepticforum.com/

[Maddad]

Saying that it did happen once, though while accurate, allows you to avoid the crucial question. Why? Luck? It's equivalent to winning the megabucks lottery every week of your life. I could accept winning it once, and there have been cases of someone winning it twice, but uncounted trillions of times? In succession, without ever missing? Are you comfortable with a level of luck on this scale? And if you are, are you willing to say that the luck must be more zeros against that you are willing to type for even this astounding fortune?

We blithly pass off the organization of the first self-replicating molecule by saying that given enough time, it could happen. But there isn't enough time to raise the level of chance out of these fantastic odds. If we cannot come up with a better explanation of how these first self-replicating molecules came into being, then we are left with only one answer. An act of God.

[Centaur]

maddad said:

An act of God.

Although seemingly simply stated, that is a hypothesis with even greater underlying complexity, requiring an explanation of his/her/its creation, powers, and motivation.

[Maddad]

Got anything better?

[Centaur]

maddad said:

Got anything better?

This is a scientific forum. The stated hypothesis seems to be the fallback answer for which its adherents do not feel proof is necessary. Yet some of those same people will demand that all things that science could ever determine should have been revealed by now, or else certain imaginings must be accepted. If all of nature were understood, then all of today's working scientists would be teachers and not researchers. Apparently an unproven conjecture of immense complexity, when presented in one's youth by authority figures, is to be assumed as the catchall answer when one is otherwise mystified.

Are the professor’s odds those against life initiating anywhere at any time? Or do they refer to one specific place and time? Or was a desired conclusion already determined before knocking down a straw man with made up numbers? If we're going to play the odds guessing game, I could put the chance at less than one in a googolplex factorial that a magical entity suddenly sprang into being with all of its superpowers intact. If such an occurrence were actually more likely than that, please have the professor put a number on it with full explanation. I'd also ask the professor to describe more precisely how he determined the probabilities regarding a natural explanation of the beginning of life?

I could point out that there are theories of the existence of a countless number of universes - perhaps enough of them to overcome any astronomical odds against life. Then again, maybe the odds aren’t so great. Certain naturally occurring phenomena may have been undiscovered or overlooked. Let’s not allow reliance on seemingly simple yet actually complex supernatural explanations to deter us from efforts to unveil nature’s secrets.

[Maddad]

The difficulty is that the means cited by these people claiming science is that there isn't enough time. What is the minimum genome, about 300,000 base pair? That's a pretty honkin' solid guess Centaur, yet it means that before you can have self replication, you need 300,000 of these abundant molecules to come together in the proper sequence. This means that you need to try ten to the 180,000 (300,000 divided by the log of four) th power combinations before you get one that works.

If you assume that the universe has always been the volume that it is now, that the primordal soup of chemicals in our early oceans permeated the entire universe since the big bang, and that each cubic micrometer of this environment tries a new combination of base pair, without duplication, every microsecond since the beginning of time, then you will slightly overestimate the chances for the occurance of life. The universe is what, 10^85 cubic centimeters? Since there are 10^12 cubic micrometers in a cubic centimeters, that's a volume 10^97 cubic micrometers for the universe. Since a year has 30 million seconds, it has 3x10^13 microseconds. Since there are 10^10 years in the lifespan of the universe, there have been 10^23 microseconds in this time. That's all.

Coupled with a volume of only 10^97 micrometers, you only get 10^120 tries at randomly creating a self-replicating molecule. However, you need 10^180,000 attempts to come up with an even money shot at it. The universe would have to be 10^179,880 times as old as it currently is to give life a 50/50 shot with random selection.

(Actually though, it's slightly worse than that. 300,000 divided by the log of four is only about 180,000; it's actually more like 180,618. So you need the universe to be 10^180,498 times as old as it is now, but what's 618 zeros between friends when we're talking about numbers this big? Besides, remember that slight over-estimation of the chances of life? That's gotta be good for a couple more.)

Look, I do not support intelligent design. I am just saying that passing this problem off as "given enough time, life has to happen" just grossly misunderstands the time that would be needed. If we do not turn our minds towards getting a better mechanism, then "an act of God" becomes much more likely. Sure, I think God exists. It's the job of science, not religion, to figure out how he did this. "Given enough time, life has to happen" is gonna have Him laughing.

[Centaur]

maddad said:

It's the job of science, not religion, to figure out how he did this.

As I indicated already, life likely started far more simply than with DNA or even RNA. I would expect it was an evolving process beginning with something far less complex. Some even theorize it began with the crystals to which I earlier alluded.

Please note my earlier mention of the possibility of countless universes, perhaps expanding and collapsing ad infinitum. Eventually, in at least one place the right atoms could have gotten together.

I'm sorry, but if someone wishes others to accept a supernatural explanation, it is incumbent upon him to offer proof. He should not demand proof of his conjecture from others who are spending their good time seeking rational explanations.

I realize it is comforting for even an adult to want to believe that an all-powerful parental figure is still looking after his best interests. However, if such a supposition is to be accepted by those who were not indoctrinated in their youth, proof must be presented. Please feel free to include a full probability analysis in describing the foundation and likelihood of the emergence of a fully functioning supernatural agent.

[Maddad]

You still have a problem there. Saying that well, bubbles did it is a way of taking it out of science. Since this speculation is not possible to test, it is therefore not science. You're only trading one supernatural explanation for another.

As for something simpler than DNA or RNA being responsible for life, my guess is that you're right. Our challenge as scientists, not speculators, is to identity a simple molecule that is capable of self-replication. Then we can look at the probablity of it's coming into existence. Once we get reasonably small numbers, then we have a chance of saying that life could have started this way. But until we get there, we aren't there.

[Centaur]

Once you eliminate the impossible, whatever remains, no matter how improbable, must be the truth.

Sherlock Holmes (Arthur Conan Doyle)

[Centaur]

To surrender to ignorance and call it God has always been premature, and it remains premature today.
Isaac Asimov

Here’s a link to an article regarding molecular precursors to life within a thread at astronomy.com:
www.astronomy.com/ASY/CS/forums/291488/ShowPost.aspx