Posted on 10/25/2001 9:13:53 AM PDT by RightWhale
Is there obvious proof that we could be alone in the Galaxy? Enrico Fermi thought so -- and he was a pretty smart guy. Might he have been right?
It's been a hundred years since Fermi, an icon of physics, was born (and nearly a half-century since he died). He's best remembered for building a working atomic reactor in a squash court. But in 1950, Fermi made a seemingly innocuous lunchtime remark that has caught and held the attention of every SETI researcher since. (How many luncheon quips have you made with similar consequence?)
The remark came while Fermi was discussing with his mealtime mates the possibility that many sophisticated societies populate the Galaxy. They thought it reasonable to assume that we have a lot of cosmic company. But somewhere between one sentence and the next, Fermi's supple brain realized that if this was true, it implied something profound. If there are really a lot of alien societies, then some of them might have spread out.
Fermi realized that any civilization with a modest amount of rocket technology and an immodest amount of imperial incentive could rapidly colonize the entire Galaxy. Within ten million years, every star system could be brought under the wing of empire. Ten million years may sound long, but in fact it's quite short compared with the age of the Galaxy, which is roughly ten thousand million years. Colonization of the Milky Way should be a quick exercise.
So what Fermi immediately realized was that the aliens have had more than enough time to pepper the Galaxy with their presence. But looking around, he didn't see any clear indication that they're out and about. This prompted Fermi to ask what was (to him) an obvious question: "where is everybody?"
This sounds a bit silly at first. The fact that aliens don't seem to be walking our planet apparently implies that there are no extraterrestrials anywhere among the vast tracts of the Galaxy. Many researchers consider this to be a radical conclusion to draw from such a simple observation. Surely there is a straightforward explanation for what has become known as the Fermi Paradox. There must be some way to account for our apparent loneliness in a galaxy that we assume is filled with other clever beings.
A lot of folks have given this thought. The first thing they note is that the Fermi Paradox is a remarkably strong argument. You can quibble about the speed of alien spacecraft, and whether they can move at 1 percent of the speed of light or 10 percent of the speed of light. It doesn't matter. You can argue about how long it would take for a new star colony to spawn colonies of its own. It still doesn't matter. Any halfway reasonable assumption about how fast colonization could take place still ends up with time scales that are profoundly shorter than the age of the Galaxy. It's like having a heated discussion about whether Spanish ships of the 16th century could heave along at two knots or twenty. Either way they could speedily colonize the Americas.
Consequently, scientists in and out of the SETI community have conjured up other arguments to deal with the conflict between the idea that aliens should be everywhere and our failure (so far) to find them. In the 1980s, dozens of papers were published to address the Fermi Paradox. They considered technical and sociological arguments for why the aliens weren't hanging out nearby. Some even insisted that there was no paradox at all: the reason we don't see evidence of extraterrestrials is because there aren't any.
In our next column, we'll delve into some of the more ingenious musings of those who have tried to understand whether, apart from science fiction, galactic empires could really exist, and what implications this may have for SETI.
Write it in stone, it lasts longer than steel, paper or CDs/DVDs. LOL!
After all, 115 years ago, you could have built a radio or TV transmitter powerful enough to be received halfway around the world, but 100% of your output on those airwaves would have zoomed right through every human on the planet, and they all would have remained utterly clueless that the signals were ever there. Not only didn't they have radios and TVs, only the brightest scientific minds of the day even considered the theoretical possiblities of radio. We today could be right in the middle of just such cluelessness. Maybe 10-15 years down the line someone will invent some wild new communications system based on nothing even vaguely like the electromagnetic spectrum, and the moment he builts the receiver and turns it on, "HELLO EARTHLING" will pop out of it!
Or, maybe not.
And that's just one of an infinite number of possibilities. Personally, my belief is that human civilization simply is not yet anywhere near the point where we can even start to comprehend a meaningful number of the other possible ways to detect intelligent life on other worlds. We're getting there, but we ain't there yet. And until we are, I think it's presumptuous of us to even ask "Maybe they aren't there?" They could be right under our noses, and we're just too backwards to see them at this point.
Put far more succintly: We're not looking out there for evidence of "intelligent life"; we're only looking for evidence of life NO MORE INTELLIGENT than we currently are circa 2001 AD. And since all other potential civilizations out there that can't be much better off that we are, are most likely dealing with the same internal crap that we are - wars, politics, just trying to work our way towards a truly technological wonderland - they're probably not putting out much in the way of receivable data. Even we only have a little under 100 years' worth of transmissions out there; that material has only made it to a couple of other solar systems at this point, and those systems are almost unquestionably devoid of life.
I really believe this- I am not joking!
I think we just have not figured out the technology to bend space so as to travel far away instantaneously...
I don't see any reason to be so pessimistic about travel speeds. We can already, now, imagine ways to travel some significant fraction of the speed of light, v>.1c. If we felt like spending the money, we could use these technologies today, or very soon. There are the nuclear propulsion systems of the Daedalus project, solar sails, etc.
It's not extravagant to speculate that in several centuries we would be capable of traveling even faster and at a practical level of expense.
I heard the same type of arguments when I was in school for other solar systems. I had a prof who once told me we would never discover a solar system outside of our own. We see life in the most unusual places. Places we would die in seconds. This universe may be teeming with life that does not resemble us in the least. If they become tool builders the laws of physics dictates that RF is RF no matter who or what generates it.
Not really. Such a conclusion requires scores, if not hundreds, of assumptions.
I'd be pretty embarrassed if my international reputation were based on such a sloppy, off-handed comment.
There has been an estimate of over 14,000 stars within 100 light years from earth. So how do we know they are devoid of life?
Well, in the ST universe, it's been shown a number of times that you continue to exist, think, and feel while inside the transporter beam, so it's not a matter of ripping your atoms apart to calculate what a "you" is (killing you in the process) and then using that data to build a replacement "you" on the other end.
You're right, though, that as of 2001 the only way anyone has been able to consider building such a device is to do just that: Kill and dissect your scrawny ass and then put a fresh copy together again on the other side. Luckily, the only known way to pull this off today would require a "human hard drive" that could hold more bits of data than there are atoms in the entire universe ... just to beam ONE GUY. So I don't think we have to worry about it happening anytime soon. <grin>
Is it that many? Damn it, I just read somewhere the other day that there were only a few that close. I gotta stop getting my scientific data from the Taliban Instutute of Technology.
Though, in a way, you could probably conjecture that there aren't any 2001-esque levels of huminoid intelligent life there, because we would have picked up their stuff too, eh?
The "scientists" that promote SETI do so out of RELIGIOUS desire, NOT because of "science."
If we don't know how life began on earth, how can we possibly make statements about the probabilities that it has arisen elsewhere. The Saganites are good entertainment, though.
Ummm...YOU need to get real. You obviously don't have the slightest clue about chemistry or reaction dynamics. You aren't even grasping the fundamentally obvious. You'll find damn near any chemical you want in a large, dirty, energetic soup in some quantity, even if very minute. Complex organics don't spontaneously assemble, they bootstrap, and it won't take very long for that to happen in a chemically rich and energetic environment. There are many sources of extremely rich and complex organics on this planet that are not biological in origin. As long as you think large-scale spontaneous assembly is the basis of organic chemistry or bio-chemistry, you'll be embarrassingly wrong. The amount of incremental assembly required to create self-replicating organic molecules is actually quite small. There are many different kinds of self-replicating molecular systems known to science; DNA/RNA is just one of the multitudes possible.
My point about commercial production is that a reaction pathway either exists or it doesn't. We don't do any magic in commercial reactors that doesn't happen in nature already, the primary difference is that our product is purer.
Of that I have no idea :)
My search continues!
Me, too. Luckily, it's not. ;^)
Sure, this is possible. They might be so big or so small or so different somehow that they would be of no concern to us or us to them. Communication might not be possible, and even if it were their value system could be so different that nothing could be discussed. We would be looking for something that might be either a competitor or trading partner, something that could interact with us or be the subject of a master's degree project. I expect we will find bacteria everywhere out there; nothing more.
If a race of ant-like creatures with a hive-mind(like Borg, or Communists lol) were somehow able to achieve civilization and SOME level of innovation(dedicated "research drones" ??) than maybe the only conflict they would find would be with other species.
Maybe there's an intelligent but sublight speed bound race of gas or energy. That'd make it kind of difficult to know how and where to look. Then again, maybe things are like Star Trek and an advanced race sprinkled some DNA in the primordial stew millions of years ago, and we all came out somewhat humanoid in form. I have no idea...
Frankly, I don't know if we want to find out. There's no guarantee that the alien race we meet will be any different than the Spanish were in the Americas(or worse, King Leopold's rule in the Congo)
This sure is news to me! I am actively involved in a SETI search with a group of dish antennas, and I certainly do not worship them or my search.
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