Kuro5hin.org: technology and culture, from the trenches
create account | help/FAQ | contact | links | search | IRC | site news
[ Everything | Diaries | Technology | Science | Culture | Politics | Media | News | Internet | Op-Ed | Fiction | Meta | MLP ]
We need your support: buy an ad | premium membership

The Fermi Paradox and the Weak Anthropic Principle

By arvindn in Science
Wed Jan 22, 2003 at 10:13:28 AM EST
Tags: Science (all tags)

The Fermi paradox is well known: Why haven't we met any aliens? The conditions essential for the existence of life and the evolution of intelligence are not rare, especially considering the number of stars in the galaxy. So we appear to be observing an event of very low probability.

However, other events of very low probability are observed in cosmology. The expansion rate of the universe appears to be exactly equal to what is required for preventing it from collapsing on itself as well as expanding beyond control. The Anthropic Principle is an intriguing theory which is a possible explanation of the latter phenomenon. Could it be the answer to the Fermi paradox as well?

The Weak Anthropic Principle states:
The observed values of all physical and cosmological quantities are not equally probable but they take on values restricted by the requirement that there exist sites where carbon-based life can evolve and by the requirement that the Universe be old enough for it to have already done so.
So, had the expansion rate of the universe been different, intelligent life could not have evolved, but since it has, the expansion rate must have precisely the value that it does. As if that weren't bad enough, the strong form of the principle assumes the existence of infinitely many universes running in parallel with all possible parameters.

Without transgressing into philosophy, lets return to the Fermi paradox. One obvious answer, of course, is that any intelligent civilization will self destruct before it can reach out to the stars. But that's evading the issue; we must work with the assumption that there is a non-negligible probability that a civilization will escape destruction before trying to colonize or at least communicate with other civilizations.

Suppose we say that every intelligent civilization goes on to expand (instead of merely sitting around and trying to communicate), and colonizes all planets in its path (and consequently destroys the native civilizations). What evidence is there for this possibility? It certainly corroborates well with the fact that we haven't met any aliens: If any aliens had come this way, it is exceedingly likely that they would have reached before there were any earthlings capable of asking the question "Where are the aliens?". (the anthropic principle). And we would have been destroyed without knowing what hit us.

Does that mean that we are the first civilization to evolve to ask the question? No! There are many civilizations; each goes through 4 stages in its evolution:

  • Life does not yet exist.
  • Life exists, but can't yet ask the question.
  • Civilization has evolved enough to ask the question.
  • The civilization has advanced enough technologically to start on its own process of expansion.
Obviously, stage 3 will be extremely short (compared to the others) for any civilization, and the chance that it will meet alien life for the first time during this stage is very small. So you see, the hypothesis has explained the observation.

The conclusion can be summarized as follows:

Since they haven't come here and killed us already, we'll go out and meet them halfway.

But what happens when two expanding civilizations meet? Wouldn't there be wars which we should have observed? Perhaps. But perhaps not. May be there haven't been any close enough for us to observe. Or may be they are not fought on a gigantic scale but with nanotechnology.

Thus, although it is questionable that a colonizing civilization would always destroy the natives, the hypothesis provides an answer to the Fermi paradox based on the anthropic principle. I think the idea requires careful thought.


Voxel dot net
o Managed Hosting
o VoxCAST Content Delivery
o Raw Infrastructure


Related Links
o Also by arvindn

Display: Sort:
The Fermi Paradox and the Weak Anthropic Principle | 138 comments (117 topical, 21 editorial, 0 hidden)
As for (3.66 / 6) (#1)
by medham on Tue Jan 21, 2003 at 06:22:32 AM EST

"Where are they?" I suggest a viewing of John Carpenter's They Live!. In short, they're all around, and they think that poor people don't pay enough taxes.

The real 'medham' has userid 6831.

That's why I wear my sunglasses at night (n/t) (4.00 / 1) (#5)
by LaundroMat on Tue Jan 21, 2003 at 07:10:52 AM EST


"These innocent fun-games of the hallucination generation"
[ Parent ]

Forgetting the scale of time (4.57 / 14) (#2)
by BadDoggie on Tue Jan 21, 2003 at 06:35:54 AM EST

Humans have been around a million years, depending on whether you count Homo erectus and/or Homo habilis.

We've been "civilised" for about five to ten thousand years.

We've been actively and realistically pursuing contact outside our planet for about fifty years.

Maybe they don't want to talk to us. The Chinese were quite content to be left alone in their "Central Empire" for 5,000+ years.

There may be an almost infinite number of stars out there, but there are only 133 to 1,038 of them near enough to have even heard us saying "hello". Not even 3,000 could have yet received the earliest radio transmissions.

We're also trying to listen for someone else talking. The SETI project, using more computing power than ever thought possible, is making educated guesses and trying to sift through a lot of noise to hear someone else.

For comparison, you and I will go outside, each shoot a high-powered rifle and try to hit each other's bullets. I'm not going to tell you when I'm shooting, nor in which direction.

What's the problem? I can't possibly be more than about 13,000 miles away from you!

Be patient.


"The line between genius and stupidity is very fine indeed, but you're so far away from the line that it doesn't matter." --

The point is that everybody's shooting! (3.25 / 4) (#7)
by arvindn on Tue Jan 21, 2003 at 07:45:40 AM EST

For comparison, you and I will go outside, each shoot a high-powered rifle and try to hit each other's bullets. I'm not going to tell you when I'm shooting, nor in which direction.
That's not an accurate analogy. What if everyone went out and started shooting? That's what the Fermi paradox says. There are so many planets on which life could have evolved, that we should have heard from at least one of them. It is quantified by the Drake equation. Drake estimated 10000 communicative civilizations in our galaxy! That's what I meant when I said The conditions essential for the existence of life and the evolution of intelligence are not rare, especially considering the number of stars in the galaxy. Maybe I should have made it clearer.

One more thing: if aliens wanted to communicate, they wouldn't go broadcasting at random. They would probably identify stars where there is a possibility of a life-supporting planet and broadcast in the direction of the star (They can afford to do this for millions of stars.) That is why SETI's failure is all the more surprising. And nobody's saying that they should have heard our broadcasts before trying to contact us.

There's a paradox alright. And there's no obvious solution. That's why it became famous. We are not likely to find a definitive answer in the near future (assuming we continue not to hear aliens). The article proposes one possible explanation. Just possible, not likely or even probable.

So you think your vocabulary's good?
[ Parent ]

My analogy is correct (3.66 / 3) (#8)
by BadDoggie on Tue Jan 21, 2003 at 08:09:54 AM EST

With less than one star in ten cubic parsecs, they're spread out pretty thin. Of those stars around us, only some might have planets which could support life. Of them, which might be able to receive or broadcast a transmission?

Also, I presented the idea that we are both going to shoot. I didn't say we have to shoot randomly. We're both going to try and guess where the other might aim to make contact, so we'll need a common point of reference, like the Moon or Sun. In astronomy, those guessed points are either star clusters, stars which look like they might have planets, and a pretty black area in space with less than average stray radio signals.

I'm not saying they have to hear us before they'll talk to us. It's just that somebody has to go first. Maybe we're that somebody. Maybe not. So we broadcast and search for signals.

Douglas Addams was right: the population of the entire universe is 0, since there's an (effectively) infinite number of stars and a finite number with planets supporting life as we know it.

P.S., I planned to shoot my rifle toward the centre of the Moon at perigee during perihelion.


"The line between genius and stupidity is very fine indeed, but you're so far away from the line that it doesn't matter." -- Parent ]

Analogy (4.33 / 3) (#67)
by Znork on Wed Jan 22, 2003 at 05:09:36 AM EST

Your analogy is correct, in a local neighbourhood sort of way (ie, it's only us and the alpha centaurians in the entire galaxy), but not really applicable for the Fermi paradox.

According to the Fermi paradox, if life and civilization was in any way common (as in likely to happen rather than complete freak accident unlikely to ever be repeated anywhere else), the chance is high that at least one of those civilizations would engage in an exponential expansion scheme (after all, someone else might be developing WMDs so lets make sure...).

Even at sublight speeds, with technology available to us within several decades, considering the age of the galaxy, such an exponential expansion wave would consume each and every habitable planet in the galaxy within a cosmic blink of the eye. With such a scheme in place, imagine each and every planet in the galaxy aiming their rifle at you, constantly shooting, for the last several million of years with the intent to colonize/transform/assimilate/turn into gray goo.

You're gonna notice.

Read the link that arvindn provided to the Fermi paradox. Can you think of a way to counter it?

[ Parent ]

What about colonization? (5.00 / 1) (#80)
by wurp on Wed Jan 22, 2003 at 01:45:59 PM EST

Assuming that other civilized creatures, at least some other civilized creatures, spread the way basically all life on earth does, the whole universe should be populated at very nearly the maximum possible speed spreading out from the place & time that the civilization can begin spreading.

Living things reproduce exponentially, limited by the maximum rate that their environment can support.  Once you have filled up your environment, there is a  strong pressure to spread to new environments.  I would expect a civilization that can produce fast transportation to spread in a sphere with a radius expanding at nearly the speed of light.  One "ship" travels to the nearest star, while another is sent to the next nearest, etc, and there are enough planets on the outer surface of the sphere to have them basically continually populating the planets surrounding the sphere.

I don't have any answers, but I think the questions are still outstanding.
Buy my stuff
[ Parent ]

Observability. (4.57 / 7) (#4)
by traphicone on Tue Jan 21, 2003 at 06:49:49 AM EST

One note often overlooked within this topic (as it is often discussed by philosophers and not physicists) is observability. As each of light, radio waves, and even gravity travels no faster than the speed of light, no other civilization would be observable for potentially many years after having come into being.

Human projects like the Search for Extra-Terrestrial Intelligence have been monitoring the heavens for alien broadcasts for less than twenty years. Humanity has only been technologically capable of sending radio communications for a little more than one hundred years. It has been capable of sending strong broadcasts for even fewer. The proportion of stars within one hundred light years to total stars in the universe is quite literally astronomically small.

Even were we to assume that another civilization managed to develop radio long before man, the vast majority of stars (and therefore star systems) is more than 2.2 million light years away. This means that we can never see these worlds other than as they existed more than two million years ago. This long ago on Earth, homo habilis was eating his first breakfast as a newly distinct species.

Even if there is life out there, the chances of ever witnessing it or communicating with it are even smaller than the chances of it existing at all.

"Generally it's a bad idea to try to correct someone's worldview if you want to remain on good terms with them, no matter how skewed it may be." --Delirium

Time scale (4.33 / 3) (#81)
by wurp on Wed Jan 22, 2003 at 01:55:46 PM EST

Universe: 12 - 20 billion years old
Evolving life from scratch: ~4 billion years
Creation of star from which life can evolve: perhaps 6 billion years

Even on the shortest scale, that leaves 2 billion years (12 - (6 + 4)) for a civilization to evolve.  If any civilization evolves in that time which spreads like earth life does (occupying all environmental niches that it's possible to occupy) we should expect a radius of almost 2 billion light years (assuming the speed of light really is a limit) that is used by that civilization.

This implies that any civilization was much more than 100,000 years ahead of us in our galaxy should control the galaxy.  That's 100,000 years out of an available 2 billion years (0.00005).

I don't know the answer, but the question is harder than some people seem to think.
Buy my stuff
[ Parent ]

A more detailed explanation (4.83 / 6) (#6)
by motasem on Tue Jan 21, 2003 at 07:16:55 AM EST

For an interesting explanation of both Anthropic principles read the public lecture "Life in The Universe" by prof. Stephen Hawking.

Actually, (4.00 / 4) (#9)
by tkatchev on Tue Jan 21, 2003 at 08:22:47 AM EST

Something you missed -- most likely, "space travel" is physically impossible, and therefore thinking about aliens is a useless waste of time.

   -- Signed, Lev Andropoff, cosmonaut.

Untrue (3.00 / 2) (#27)
by TheOnlyCoolTim on Tue Jan 21, 2003 at 03:10:46 PM EST

Space travel has been proved possible - maybe this post will bounce through a satellite on its path to Kuro5hin (though that would be some highly inefficient routing.)

Of course, here we are discussing interstellar distances. That hasn't been empirically proven but it is extremely theoretically possible:

Build a big spaceship that's almost all engines and fuel. In the tip put a man in some sort of hibernation. Point it at Alpha Centauri. Full thrust for half the distance, then turn the ship around and full thrust for the rest of the distance to decelerate. Welcome to Alpha Centauri, our flight time was x decades/centuries.

The only hypothetical technology there is the hibernation - and you can get around that by building even more fuel and engines and putting supplies for the man and possibly his spouse and children to live on.

Unless there's some unobserved clear bubble or force field around the solar system interstellar travel is fine.

"We are trapped in the belly of this horrible machine, and the machine is bleeding to death."
[ Parent ]

Sir, you missed the most important calculation: (1.00 / 1) (#34)
by tkatchev on Tue Jan 21, 2003 at 05:25:33 PM EST

The first thing you need to do is to show a plausible and coherent estimate for energy consumption.

It could well turn out that interstellar travel needs amounts of energy that are phsycally impossible to harness. ("A third of the sun's yearly output" or something like that, for example...)

   -- Signed, Lev Andropoff, cosmonaut.
[ Parent ]

Patience (4.00 / 2) (#37)
by TheOnlyCoolTim on Tue Jan 21, 2003 at 06:15:26 PM EST

Voyager 1, if it had been pointed the right way, would reach Alpha Centauri in about 74,000 years, disregarding Alpha Centauri's motion relative to Sol (I can't find any really reliable sources on this motion. The best is here and it says that Alpha Centauri is getting closer to us.)

The Voyage probes will soon be partaking in interstellar travel, although they're not aimed at any particular system.

Did you read localroger's "Passages In The Void"? All you need is a longer viewpoint. Let's say we find no sufficiently magic technologies, but do eventually go and mine the asteroid fields and the gas giants and still the best our ship can manage with all those resources is to go ten times as fast as as Voyager 1. That's a ridiculously small percentage of c, but our ship would still reach Alpha Centauri in about 7,400 years.

"We are trapped in the belly of this horrible machine, and the machine is bleeding to death."
[ Parent ]

And now a James P. Hogan Moment (none / 0) (#48)
by localroger on Tue Jan 21, 2003 at 09:16:22 PM EST

In Voyage to Yesteryear written in the mid-80's Hogan had an Earthlike planet of Alpha being colonized by a robotic probe bearing genetic material and robots kind of like the situation in Passages, except that there was no terraforming or automatic probe-replication. There is a strong thread running through that novel of the Chironians looking up at the sky and thinking both "home" and "Aw fuck, they're coming." That probably had a lot to do with the last section of Passages reading the way it does.

I can haz blog!
[ Parent ]

Not really. (1.00 / 1) (#69)
by tkatchev on Wed Jan 22, 2003 at 06:31:19 AM EST

"Interstellar" distances are quite a bit (a huge bit, actually) larger than distances from here to Alpha Centauri.

Alpha Centauri is the best possible case; the average case might be a million or a billion times longer.

   -- Signed, Lev Andropoff, cosmonaut.
[ Parent ]

Waaaa? (3.00 / 1) (#71)
by speek on Wed Jan 22, 2003 at 09:04:26 AM EST

Alpha Centauri ~ 4 light years away Furthest possible distance between 2 stars in the milky way ~ 100,000 light years.

And the "average" distance of the closest star from any given star is probably in the order of 10-100 light years.

al queda is kicking themsleves for not knowing about the levees
[ Parent ]

You're getting closer. (2.00 / 2) (#78)
by tkatchev on Wed Jan 22, 2003 at 01:14:32 PM EST

Good point, but it only holds when we don't care which star we are travelling to.

Presumably, if humans ever decide to colonize other stars, they will only want a certain specific star. (One that has a planetary system, one that isn't too hot or too cold, etc, etc...)

How many such stars there are and how they are distributed nobody knows for sure.

   -- Signed, Lev Andropoff, cosmonaut.
[ Parent ]

Uh. (none / 0) (#134)
by Lagged2Death on Mon Feb 03, 2003 at 12:07:13 PM EST

I think the point was that when you said:

Alpha Centauri is the best possible case; the average case might be a million or a billion times longer.

You were mistaken by a very large factor. The farthest-apart stars in the galaxy are 25,000 times as far apart as Sol and Alpha Centauri. Your guess of "a billion times longer" is off by a factor of at least 40,000. Probably much more, in fact, since we won't be trying to make that longest-possible trip first, if at ever.

Starfish automatically creates colorful abstract art for your PC desktop!
[ Parent ]

Age and size (3.00 / 1) (#72)
by Znork on Wed Jan 22, 2003 at 09:35:26 AM EST

The milky way is less than 100K lightyears across. We are about 28000 lightyears from the center.

Alpha Centauri is the best possible case for us, but as far as locations go we're rather in the boondocks.

Considering that the galaxy contains many many stars that are considerably older than our sun, travelling over it at sublight speed and colonizing all of it within a very short period of time (as far as galactic timescales go) is fairly easy, assuming a species hell-bent on a geometric expansion program.

[ Parent ]

Impossible? (3.00 / 1) (#133)
by Lagged2Death on Mon Feb 03, 2003 at 11:57:56 AM EST

It could well turn out that interstellar travel needs amounts of energy that are phsycally impossible to harness. ("A third of the sun's yearly output" or something like that, for example...)

In what way is energy equivalent to 1/3 of the sun's yearly output "physically impossible" to harness?

Starfish automatically creates colorful abstract art for your PC desktop!
[ Parent ]

Species (4.36 / 11) (#11)
by DarkZero on Tue Jan 21, 2003 at 08:27:33 AM EST

One of the annoying things that I've noticed in this debate is that nearly everyone assumes that aliens will be be nothing more than Star Trek aliens: Same capabilities, same basic body structure, same instincts, same mindset... but with these really weird bumps on their foreheads indicating that they're not human. This article assumes that civilizations evolve in a certain way and contemplates why we haven't seen any wars in space. That's a mindset that's coming straight out of Star Trek, where aliens are nothing more than caricatures of human cultures.

Why does intelligent life necessarily have the ability to make tools, such as spaceships and the materials required to build them? Dolphins are supposed to be pretty intelligent and in a few thousand or million years they might even be as smart as us, but I haven't seen any indication that their fins have been evolving into hands as their brains grow more intelligent. And why would aliens necessarily have the mindest of an explorer? There are many, many animal species that prefer to just stay in their little holes as much as possible and not go far from home. Why would this instinct necessarily be dropped by an alien species if they weren't in dire need of more resources? Isn't it possible that we are the duckbill platypus of the universe, sharing important characteristics with only a handful of other species? Planets that can sustain life may not be rare, but if an explorer's mindset turns out to be rare among alien species, what are the chances that one of those few species will be relatively close to us?

And secondly, I'd just like to throw in the same question that I've always added to this debate: What if we're first? Statistically improbable as it may be, one species had to be the first in the universe that was capable of space travel and communication. That species would be pretty lonely, wondering why there doesn't seem to be intelligent life anywhere around them... sort of like us.

Why we are NOT the first (2.00 / 1) (#15)
by arvindn on Tue Jan 21, 2003 at 08:55:09 AM EST

It's simple. The sun came into existence ~ 5 billion years after the big bang. It takes less time than that for life to evolve on a planet. All that while there have been stars, and planets on them. So, its not only likely that we're not the first, it is likely that there was intelligent life elsewhere even before the sun came into being!

When thinking in a scale different from our everyday lives, it is difficult to understand how likely or unlikely things are. This is why numbers help. The Drake equation tells us that there's an extremely high probability of intelligent, communicative life outside the earth. If you want an analogy, what is the probability that tomorrow morning, everyone in your city gets a headache and decides to stay at home?

Also, the article addresses the question of seeking to explain a low-probability occurence. So an argument like "this may be statistically improbable, but..." is meaningless. The whole idea is that if our model assigns a very low probability to an observed event, then we need to look hard find a hole in the model.

So you think your vocabulary's good?
[ Parent ]

Assumptions, assumptions (4.75 / 4) (#17)
by JetJaguar on Tue Jan 21, 2003 at 12:25:01 PM EST

You're making a whole lot of assumptions based on a single observation. That's generally considered to be very bad science. How do you know it takes less than 5 billion years for life to evolve on a planet? Merely because that's the case on earth doesn't mean that it's true in general. We simply don't have the observations to make that sort extrapolation.

Second, the Drake equation is a joke, IMHO. It makes for an interesting starting point, but the further down the list of probabilities you get, the more hand-waving it takes to come up with the numbers. As such, the Drake equation is largely just an intellectual exercise and shouldn't be looked at as some sort of statement about the way the universe really is. I can't think of any of my colleagues in astronomy that loses sleep over potential consistancy problems with the Drake equation. It's just an intellectual excersize and nothing more.

[ Parent ]

Bzzt. (5.00 / 3) (#24)
by porkchop_d_clown on Tue Jan 21, 2003 at 02:10:43 PM EST

When the first stars lit up, there were no elements heavier than hydrogen, so no rocky planets, no carbon chains, no DNA.

It wasn't until the third (I think) generation of stars formed out of the supernovae of older stars that the concentrations of metals and so on rose to the point where life was possible.

"Your article (and I use that term losely) is just a ad-hominem filled rant from a right-wing extremist loony." - Psycho Les

[ Parent ]
carbon and dna (3.00 / 4) (#36)
by tichy on Tue Jan 21, 2003 at 05:35:38 PM EST

This assumes intelligent life based on carbon chains and who use DNA to store genetic information. We have no reason to believe they are necessary to all life. The idea however that a life form not based on carbon or DNA will want to colonize the stars in a Star Trek fashion is a little ridiculous. We have trouble understanding other human cultures, I don't think we can predict what the values of such a creature would be.

[ Parent ]
It's not a bad assumption (4.50 / 2) (#74)
by ph317 on Wed Jan 22, 2003 at 11:22:33 AM EST

Consider the complex underlying chemical interactions neccesary to support life as we know it, even in simple forms like Amoebas.  It is very unlikely that a system with the complexity level of even the lowest life can evolve in an environment containing only hydrogen and helium.  How many chemical compounds does that make, and how many ways can they interact?  You can think of the number of elements in the universe kinda like the number of distinct instructions in a microprocessor.  If you're only got two instructions, chance are it will be very hard to write any turing-complete code.

[ Parent ]
why assume matter at all? (3.00 / 3) (#85)
by ethereal on Wed Jan 22, 2003 at 04:37:44 PM EST

For an eternity in the live of the universe, all there was was energy. If anything, that would have been a good starting point for life, rather than the comparatively more boring and less energetic existence the universe lives today. For all we know, we're eking out an existence on the cinders of a once much greater being than we've ever imagined. We know that there was some asymmetry introduced at some point; life could easily have exploited those rough spots.

Or, if you consider that life often proliferates the most in the interfaces between two different environments, perhaps the very moment of decay from energy into matter would have been a fantastic occasion for the lives and deaths of some very fast life forms.


Stand up for your right to not believe: Americans United for Separation of Church and State
[ Parent ]

Lem got it right. (5.00 / 1) (#126)
by tekue on Mon Jan 27, 2003 at 04:34:52 AM EST

If anyone still thinks that aliens will look like in Star Trek -- or, in other words, will be in any way similar to us -- please read Stanislaw Lem's "Solaris", and a less visual but deeper "His Master's Voice". There's very little probability that we're going to be able to communicate with "aliens" on a level that we'd be able to comprehend.
Humanity has advanced, when it has advanced, not because it has been sober, responsible, and cautious, but because it has been playful, rebellious, and immature. --Tom Robbins
[ Parent ]
Dolphins intelligent? (none / 0) (#28)
by the on Tue Jan 21, 2003 at 03:49:11 PM EST

Dolphins are supposed to be pretty intelligent...
When people (who know what they are talking about) say dolphins are intelligent they are using a slightly different scale to the one used to measure human intelligence. If I say a particular human is intelligent then that might mean all sorts of things: they can write good literature, or good software, or manipulate large groups of people into doing stuff and so on. When we say a dolphin is intelligent we mean intelligent compared to other animals but not compared to humans.

The Definite Article
[ Parent ]
Sigh. (4.50 / 2) (#66)
by DarkZero on Wed Jan 22, 2003 at 04:52:13 AM EST

When we say a dolphin is intelligent we mean intelligent compared to other animals but not compared to humans.

You took what I said out of context, apparently because you did not understand what I meant by that context. When I said that dolphins were pretty intelligent, I was trying to make the point that as dolphins became more intelligent than most of their peers, they did not start to mimic human beings in any substantial ways. They did not give up their current instincts, they did not start to develop the beginnings of tool creation and manipulation (such as crude, most useless hands or poseable limbs developing), and generally, they stayed a lot like the way they were before they attained their current level of intelligence.

I mentioned this in order to make the point that the basic elements of humanity, such as tool use, do not necessarily go hand in hand with intelligence, and that an intelligent species may not have the ability or the drive to create spaceships capable of reaching Earth. It's true that dolphins could become carbon copies of human beings in the next few million years if they continue to grow more intelligent, but given the way that they have developed so far, I doubt that.

[ Parent ]

Intelligence (4.50 / 2) (#73)
by Znork on Wed Jan 22, 2003 at 09:49:42 AM EST

The basic elements of humanity, such as tool use, may not go hand in hand with intelligence but it rather does go hand in hand with opposable thumbs.

Dolphins do have the tendency to interact with inanimate objects useful fashion as far as they are capable of without extremities suitable for tool use. I agree it's dubious that dolphins would evolve in the direction of tool use tho; the survival value of tools in underwater environment seems to be less than on land. It's far more difficult to find useful materials from which to construct such tools, and fewer reasons to develop appendages for holding onto things under water (no reason to climb trees, for example).

Several land living creatures do show a tendency towards tool use and deliberate modification of their environment tho, both among our closest relatives and vastly different species (like bird nests, digging holes for eggs among reptilians, etc).

The ability to modify the environment does have a survival value, intelligence is a factor in how well you are able to perform that modification and pass on the knowledge (as far as it goes above instinct). This makes it likely that evolution will favor those species and thus intelligence and tool use should be linked quite often.

[ Parent ]

Only need one success (none / 0) (#70)
by zakalwe on Wed Jan 22, 2003 at 06:37:17 AM EST

This article assumes that civilizations evolve in a certain way and contemplates why we haven't seen any wars in space.
Actually, it would seem a bigger assumption to assume that all aliens would not be recognisable. It isn't necessary to postulate that all aliens be recognisable or even comprehensible to us, just that some form of life has arisen in the galaxy in the last few billion years that's similar enough that we could recognise their works.
Planets that can sustain life may not be rare, but if an explorer's mindset turns out to be rare among alien species, what are the chances that one of those few species will be relatively close to us?
Very high indeed, assuming they managed to be stable. Remember we're talking galactic timespans here. If any stable, expanding culture arose a few billion years ago they could have spread through the galaxy long ago.
What if we're first?
Its not impossible. In fact, without a grasp of the probabilities of any life arising we can't even know how likely it is. For all we know, the chance of any life arising is unlikely over the course of the universe, and we're just a fluke. Still, there isn't anything to suggest that life is especially unlikely, and its certainly more interesting to consider other theorys.
That species would be pretty lonely, wondering why there doesn't seem to be intelligent life anywhere around them... sort of like us.
Yeah, but who wants to meet meat?

[ Parent ]
Pluggetty-plug-plug (4.33 / 6) (#12)
by TheophileEscargot on Tue Jan 21, 2003 at 08:28:29 AM EST

I wrote an article on Radio Free Tomorrow about the Fermi paradox a while ago. Couple of extra points.

We humans have already doubled the radio output of the solar system. We should certainly be able to detect similar civilizations to are own. It also seems likely that more advanced civilizations would be even more noticeable.

The Galaxy is billions of years old, but only a hundred thousand light-years across. A stable civilization that spreads across the stars ought to have taken over the galaxy long ago, if one existed.

There are lots of different explanations for the Fermi paradox. One set of explanations is that technological civilizations have only a short lifespan before they die out or "transcend". Another set is that the galaxy is periodically "sterilized" by gamma-ray bursters (or replicators or something else) that wipes out all the existing civilizations, so everyone else has to start from scratch. Another set is that all the other civilizations are deliberately hiding, or deliberately isolating us. Or finally, we could just be alone.
Support the nascent Mad Open Science movement... when we talk about "hundreds of eyeballs," we really mean it. Lagged2Death

What we know (3.33 / 3) (#14)
by medham on Tue Jan 21, 2003 at 08:45:24 AM EST

Is not all there is. Hark: infinity implies by definition that there are an infinite number of subtly (and not-so subtly) variant Earths within that which IS.

The real 'medham' has userid 6831.
[ Parent ]

There's no infinity. (3.00 / 1) (#56)
by TheOnlyCoolTim on Tue Jan 21, 2003 at 10:07:38 PM EST

There seems to be a limited amount of space in the universe and even if there is infinite space there is a limited amount of mass.

There could be multiple universes, but they'd be much harder to get to.

"We are trapped in the belly of this horrible machine, and the machine is bleeding to death."
[ Parent ]

The End of the Universe (2.00 / 1) (#63)
by metalfan on Wed Jan 22, 2003 at 01:02:03 AM EST

This has always boggled me. Supposedly infinity can't exist. But what would happen if I were to find the end of the universe? Would I just bounce off it and say to myself, "Well that looks like the end, better turn around and go home now."

If there was a wall of some sort at the end, what would be on the other side of it?? Does anybody know of any books/publications that discuss this?

[ Parent ]
As far as I know (4.33 / 3) (#64)
by John Milton on Wed Jan 22, 2003 at 01:44:36 AM EST

In a closed universe, if you continued in a straight line, you would eventually come back to your starting point. If this doesn't make sense, imagine and ant traveling in a straight line around and apple.

"When we consider that woman are treated as property, it is degrading to women that we should Treat our children as property to be disposed of as we see fit." -Elizabeth Cady Stanton

[ Parent ]
Whoaaa (none / 0) (#82)
by Mister Proper on Wed Jan 22, 2003 at 02:03:27 PM EST

That sounds pretty crazy. Very interesting.

Does this imply that there's light that has traveled through the universe multiple times? Or is to that happen in the future as the result of the universe expanding less and less fast?

[ Parent ]

On the Universe (none / 0) (#86)
by mberteig on Wed Jan 22, 2003 at 08:27:57 PM EST

There is a very interesting thread related to this. It discusses the expansion of the universe and what exactly that means.

Agile Advice - How and Why to Work Agile
[ Parent ]
No... (4.00 / 2) (#105)
by fluffy grue on Thu Jan 23, 2003 at 10:03:04 PM EST

The act of travelling beyond the "boundary" of the universe would cause the boundary itself to move. The "size" of the universe is just given as the distance which the oldest photons have travelled; anything beyond that 12e12 light-year distance we simply can't know about, because there's no way for any observable phenomena to have come from further away.

Like, by the time you could have gotten to the "edge" of the universe, the universe would have continued to expand by that same amount. You spend 12e12 years getting to the edge of the universe, during which time it's expanded to 24e12 lightyears, so you spend another 12e12 years at which point it's expanded to 36e12 lightyears, and so on.

Of course, that doesn't answer your question. :)

I think that the question itself is based on incorrect assumptions. Common-sense reasoning only applies to the human scale; once you get smaller than a drop of water or larger than a star system, things get wacky.
"Is not a sentence" is not a sentence.
"Is not a quine" is not a quine.

[ Hug Your Trikuare ]
[ Parent ]

That point is non-obvious (4.75 / 4) (#22)
by porkchop_d_clown on Tue Jan 21, 2003 at 01:54:38 PM EST

and deserves expansion. You said

The Galaxy is billions of years old, but only a hundred thousand light-years across. A stable civilization that spreads across the stars ought to have taken over the galaxy long ago, if one existed.

Most people not be aware of the argument supporting this: that even a very slow rate of expansion (one existing planet colonizes a new planet every n years) it's still a geometric progression - as new planets are colonized the rate increases until planets are being colonized continuously and, slightly later, the galaxy becomes "full".

"Your article (and I use that term losely) is just a ad-hominem filled rant from a right-wing extremist loony." - Psycho Les

[ Parent ]
Some Archived Content (none / 0) (#92)
by thadk on Thu Jan 23, 2003 at 09:43:29 AM EST

There's an old MLP in the new archive on the Fermi Paradox and how gamma ray bursts and subsequent extinction events might be a solution. Just made it into the archive by a week too.

[ Parent ]
Why haven't we met any aliens? (3.25 / 4) (#16)
by lb008d on Tue Jan 21, 2003 at 10:15:47 AM EST

How about this: a sufficiently advanced civilization has a high likelihood of developing nuclear weapons and wiping itself out before being able to travel in space.

"Kuro5hin: politics and pretension, from the $3,000 leather recliners on the hill overlooking the trenches."DarkZero

Why nuclear (3.62 / 8) (#25)
by kerinsky on Tue Jan 21, 2003 at 02:16:44 PM EST

Why is nucear annihilation still the bogeyman in today's enlightened day and age. I'm only 21, but I've never been worried much about nukes wiping out humanity. Someone somewhere has to make a specific choice to wipe out the human race before it can happen. Genetic engineering and nanotic bring out the plausibility of "whoops I killed humanity" senarios. Black or grey nanotech goo seems the most serious to me as it seems most likely to be able to planet jump once we set up offworld colonies. Genegeneered superplagues or possible, but I'm almost more worried that we'll modify our own genetic structures so at to leave a deadly backdoor for some natural pathogen.

Nukes are so 1960's and comets or asteroids were passe by 2001. If I'm going to be paranoid I demand entertainment as well, give me a novel by Gibson, Clark or Crichton. Monofiliment blades an internet that can kill you, homicidal AI's and black monoliths full of stars . Resurrected velociraptors too, once they figure out how to use doors its only a matter of time before they figure out how to operate F-22's and M1-A2 Abram's right?

[ Parent ]

Why not? (4.66 / 6) (#53)
by dennis on Tue Jan 21, 2003 at 09:40:32 PM EST

Ah, kids these days, who don't know what it felt like to have 30,000 nukes on a hair trigger pointing at your head. We almost went to war over Cuban missiles, and on four publicly-known occasions were at risk of going to war over false alarms.

Black monoliths full of stars? That's so 1968 :)

[ Parent ]

Possible explainations (3.66 / 3) (#18)
by pyro9 on Tue Jan 21, 2003 at 12:32:23 PM EST

We need to examine a few of the basic assumptions for explainations.

One, extrasolar travel may be so difficult that most civilizations stay in system or visit only near neighbors.

We assUme that everyone would develop radio the same way we would and that they would continue to use it the way we do now. What if the typical course of development for a civilization is to get to ultrawideband within a few decades of pervasive radio use (much as we might). That would be a lot harder to detect. The window of detectability (using our technology) could be quite small.

It could be that the equivilant of alien radio and television shows have passed the Earth several times already, but the ancient Romans (etc) couldn't hear them.

It is even posible that we have been visited or our television signals decoded, but then declared a 'nature reserve' to give us time to develop into a decent civilization.

The future isn't what it used to be
Intellegence as we know it means jack without... (3.00 / 2) (#19)
by biggs on Tue Jan 21, 2003 at 12:47:38 PM EST

a cozy environment. Humans are actually pretty stupid... the only reason we have evolved as well as we have scientifically is because a cozy environment lets us sit around and think about silly things. No single human can all by itself expand very far in terms of math and science. We depend on others to create an environment where this is possible. Perhaps intelligence can evovle in less social life forms? If so, there may be aliens 1000 times more intelligent than us and it never goes to any good use because they are too busy just getting by and fending for themselves. So at any rate my point is the Fermi Paradox seems to not just speak of intelligent life, but social intelligent life on a planet with abundant resources.

"Rockin my 'hell I made it' wetsuit stitch so I can swim in elevators crazy wet through piss" -Cannibal Ox
Chicken and the egg (none / 0) (#104)
by fluffy grue on Thu Jan 23, 2003 at 09:57:06 PM EST

We have leisure time and a cozy environment because of our intelligence (or, more specifically, because of the intelligence of hundreds of generations of H. Sapiens). We have our intelligence because of the leisure time and a cozy environment.

But it's not a paradox; it's resolved in the same way as the chicken and the egg (at least, if you believe in evolution).
"Is not a sentence" is not a sentence.
"Is not a quine" is not a quine.

[ Hug Your Trikuare ]
[ Parent ]

Other conditions... (none / 0) (#124)
by csmiller on Sun Jan 26, 2003 at 04:34:39 PM EST

It also helps if the intelligent animals develop on land, and that they have dexterous limbs.

For example, consider the other intelligent animals on our planet;

  • Elephants
  • Octopuses, (and kindred species)
  • Dolphins, (and kindred species)

I'm deliberately ignoring other great apes here, as there is no reason why they couldn't develop as H. Sapians did.

Elephants aren't really capable of interacting suptlety with their environment. Their trunks just aren't capable of fine manipulation of small objects, which aids discoveries.

Octopuses' tentacles are capable of fine manipulation, but they live underwater, which makes discovering electricity very difficult, probably impossible.

Dolphins have both disadvantages

[ Parent ]

conditions for life (3.00 / 1) (#20)
by jjayson on Tue Jan 21, 2003 at 01:38:49 PM EST

he conditions essential for the existence of life and the evolution of intelligence are not rare, especially considering the number of stars in the galaxy.
I thought that we hadn't observed a single earth-like planet capable of supporting life as we know it. Earth seems to have a monopoly on liquid water, as far as I know. How do you get the idea that the coniditions for life are "not rare" from this?
Smile =)
* bt krav magas kitten THE FUCK UP
<bt> Eat Kung Jew, bitch.

Earth like planets (3.00 / 2) (#21)
by porkchop_d_clown on Tue Jan 21, 2003 at 01:48:17 PM EST

Are much, much, harder to detect than jupiter sized gas giants.

Remember - planets are too small to observe directly, their existence is inferred by their effects on the motion of their parent star.

The effects of small planets on their stars is miniscule compared to the effects of large planets that might be orbitting the same star.

"Your article (and I use that term losely) is just a ad-hominem filled rant from a right-wing extremist loony." - Psycho Les

[ Parent ]
exactly... (4.00 / 2) (#23)
by jjayson on Tue Jan 21, 2003 at 02:04:16 PM EST

which brings us right back to the question of where that statement came from. We have yet to observe anything that can support life as we know it, yet the author is claiming that they are almost common.

Smile =)
* bt krav magas kitten THE FUCK UP
<bt> Eat Kung Jew, bitch.

[ Parent ]
Astronomical Statistics (4.33 / 3) (#26)
by JetJaguar on Tue Jan 21, 2003 at 02:18:34 PM EST

Basically it comes down to size distribution statistics, gas/dust electrostatic-gravitational forces and instabilities, etc, etc. Astronomers have been doing these studies for a long while with reasonably good predictions (within about an order of magnitude).

The upshot of all these studies is that a relatively large number of small rocky bodies form during the collapse of a proto-stellar nebula, all of which have a propensity to stick to one another forming planets. The distribution statistics indicate that smaller bodies are favored over larger ones, meaning that statistically speaking, there should be far more earth-sized planets than gas giants. The problem is that the small planets are all well below the detection limits of our best telescopes (even Hubble). So, ultimately the question is unanswered, but we have unconfirmed indications based on a number of pretty well established models (that work very well when dealing with the gas giants that we do see), that there are a sizeable number of earth-sized planets.

Basically what this means is that astronomers are pretty sure this is how things work out, and it's only a matter of time before we are able to build a telescope of some sort with the ability to detect the smaller planets, but until that time comes, the result will remain unconfirmed.

[ Parent ]

Are we sure these models are right? (none / 0) (#30)
by jjayson on Tue Jan 21, 2003 at 04:03:13 PM EST

I think I remember that in the last few years they discovered drastically more planets than they originally thought. I could be wrong since I am not an astronomy or physics person.
Smile =)
* bt krav magas kitten THE FUCK UP
<bt> Eat Kung Jew, bitch.

[ Parent ]
Scaleing factors (4.66 / 3) (#31)
by JetJaguar on Tue Jan 21, 2003 at 04:46:36 PM EST

Well, as I alluded in my previous post, the low-mass planet end of the models haven't been confirmed, so there is some wiggle room there, but I think the high mass end is doing pretty well. It is possible that there could be an unknown factor that might affect the low mass part of the distribution, but if there is, we would see that in the high mass portion as well because the high mass planets have to move through the low mass portion of the distribution while they are growing.

What the debate has been about over the last few years has more to do with the unexpected discoveries and oddities, like gas giants that appear to be orbiting very close to their "parent" star (which, according to the models isn't something that is very likely to happen, though not impossible). That's kind of a different question and gets into another one astronomy's stranger quandries: selection effects.

Selection effects are biases that make their way into observations as a result of peculiar object selections. For example, if you wanted to study stars, the simple minded approach is to start with the brightest (and hence easiest to observe stars), the problem though is that this really skews your statistics, because nearly all the brightest stars in our sky our actually rather atypical stars and as such they are not an accurate cross section of all the stars in the galaxy, the majority of which are too small and too faint to observe properly.

Similarly for the case of the gas giant planets, it is likely that we are seeing a selection effect there. We are detecting these peculiar planets simply because these are the ones that are so oddball and extreme that they are easy to see. The more mundane ones are much more difficult and will require a string of highly accurate observations spanning decades before they can be confirmed. Whereas most of the planets discovered to date have only involved a few months up to a couple of years worth of observations. That sort of observing program would be naturally biased towards detecting odd-ball gas giants in strange orbits (in fact, that's about all you could detect with that sort of observing program).

[ Parent ]

Oh yeah (4.50 / 2) (#32)
by JetJaguar on Tue Jan 21, 2003 at 04:58:18 PM EST

I was going to say something about scale factors too, but got off on the selection effect tangent.

What I was going to say is that the actual number of planets observed aren't really important as far as the models are concerned. What comes out of a size distribution simulation is a "normalized" size distribution that you apply a scale factor to based on, for example, the actual number of planets of mass x that you have observed and then scale the rest of the distribution based on that number. So the actual number of observed planets really isn't what people have been debating over the last few years, most of the debate essentially boils down to figuring out how the selection effects are biasing the observations.

[ Parent ]

great explanation, but... (4.00 / 1) (#33)
by jjayson on Tue Jan 21, 2003 at 05:07:58 PM EST

I was more concerned that planet formation models might be skewed. My logic was that if in the last few years they have discovered far more large planets than they originally expected, this might not be evidence of more planets in general (a uniform scaling), it might me be evidence that the models are skewed and expected more smaller planets than they should. Since there is only finite matter and we have much better estimates as to that quantity, all these unexpected large planets would abate Earth-size planet formation.
Smile =)
* bt krav magas kitten THE FUCK UP
<bt> Eat Kung Jew, bitch.

[ Parent ]
Right (5.00 / 2) (#35)
by JetJaguar on Tue Jan 21, 2003 at 05:29:17 PM EST

You are correct, the problem though, is that the low mass portion of the models are unconfirmed. At this point, the scale factor is all we can observe, until observation of the low mass planets can be made. As I said, it is possible (though I would say quite unlikely) that there could be some unknown factor that could affect the low mass numbers, but until we can actually observe them, we just don't know. However, based on what I know about the models, and the physics of it in general, I don't think the models are going to be so far off that it's going to significantly affect our ideas about life on other planets... No matter how the final distribution works out, I am quite certian that there will be plenty enough small rocky planets. It's just not very likely that the models are going to be *that* far off. The main reason I say this, is that all the big gas giants start out the same size as the small rocky planets do: small particles of dust and ice that start to coalesce into larger bodies. No matter what you do, you are going to be making earth sized planets before you get to the really big guys. So the smaller planets are definitely out there even if we can't see them yet.

[ Parent ]
Sure we have (3.00 / 3) (#62)
by michaelp on Tue Jan 21, 2003 at 11:00:45 PM EST

We have yet to observe anything that can support life as we know it

batting one in 9 right now, which would suggest that earth like planets are fairly common.

Of course the data set is still rather small, but as our ability to see small objects increases, we've been seeing lots of the larger gassy planets around other stars & there is no reason to assume we won't start finding many smaller rocky ones once we discover how to see them.

"Every gun that is made, every warship launched, every rocket fired, signifies in the final sense a theft from those who hunger and are not fed, those who are cold and are not clothed."

[ Parent ]
Surprised nobody has mentioned... (4.71 / 7) (#38)
by localroger on Tue Jan 21, 2003 at 06:43:34 PM EST

The Singularity. Even without FTL travel, a civilization that builds one self-replicating robot spacecraft can colonize the galaxy for something like the cost of the Apollo program, in less than a hundred million years. And with all those smarter-than-human machines running around, the expectation is that they will come up with such fantastic modalities that they will be rewriting the Universe's operating system in the time it takes for radio waves to get here from Alpha Centauri.

The possibility has been brought up here in a couple of places.

I can haz blog!

Huh? (1.00 / 1) (#45)
by autopr0n on Tue Jan 21, 2003 at 08:36:10 PM EST

Why would self-replicating robot be more efficent then self-replicating people? And where are these robots going to be able to get enough matter to reproduce in the middle of space?

[autopr0n] got pr0n?
autopr0n.com is a categorically searchable database of porn links, updated every day (or so). no popups!
[ Parent ]
Robots vs. People (4.33 / 3) (#46)
by localroger on Tue Jan 21, 2003 at 08:57:37 PM EST

Robots can live a lot longer and be optimized for common environmental hazards such as vacuum and hard radiation. If FTL travel is not possible then robots will almost certainly get to the stars first, just as they have gotten to all the other planets (even the Moon, Surveyor anyone?) first. When the technology is advanced enough for those robots to self-replicate, they will be able to advance much faster than we can, dragging our shielding and life-support systems behind us.

I can haz blog!
[ Parent ]

Reproduction (4.00 / 1) (#50)
by ZorbaTHut on Tue Jan 21, 2003 at 09:22:58 PM EST

One thing I thought of in response to this: robots can spend the entire day reproducing. Humans can only dream of doing that. (okay, cheap shot :P)

Plus, robots don't have an unfortunate twenty-year training period before they're a functioning member of society - just spend five minutes copying the hard drive or equivalent, and you've got a new worker.

Matter is a different problem ;) But there are asteroid belts, planets, etc. Obviously in the middle of *deep* space they're not going to be able to do much except travel, but any solar system provides a ton of usable matter. Of course, this assumes they know enough to construct smelting facilities and so forth - it's definitely not *simple* to design a robot that can do all that, but I certainly don't see any reason why it wouldn't be possible. Once an entire solar system is consumed, launch your factories towards the nearest few dozen systems and start over again . . . it would accelerate amazingly fast, I'd bet.

Well, ignoring the multiple-decade (at best) travel times.

[ Parent ]

smelting? (none / 0) (#76)
by zephc on Wed Jan 22, 2003 at 12:28:26 PM EST

pff, it's ALL about the nanotech =]

[ Parent ]
nanotech (none / 0) (#95)
by ZorbaTHut on Thu Jan 23, 2003 at 05:50:46 PM EST

I've got to admit, I've always been a bit skeptical on how well nanotech performs . . . are we honestly talking about robots that can break down single atomic bonds efficiently? Because it seems rather clear to me that a robot with enough intelligence to work on its own (or enough circuitry to communicate with a controller) is going to have to be at least a few hundred molecules, and at that point I start wondering how finely it's really going to be able to work.

Without the ability to break down atomic bonds, of course, we're right back to the impurities problem, which is where the whole "smelting" thing comes in :P

[ Parent ]

May be a very bad idea (4.00 / 1) (#125)
by Hector Plasmic on Sun Jan 26, 2003 at 08:49:07 PM EST

Any self-replicating entity can be subject to evolutionary processes.  We may sow Voyager and reap Berserkers.

[ Parent ]
More guesses (4.00 / 1) (#39)
by Big Sexxy Joe on Tue Jan 21, 2003 at 06:58:04 PM EST

I think some of the ideas other people have are pretty good. Here's what no one has said yet.

Maybe it's that we not only did we needed intellegence, but we also needed a number of resources to develop our technology. We needed fossil fuels. We needed plants and animals which we could easily domesticate and farm. Aliens could face a number of simple missing resources which would stop their progress dead in its tracks. For example, maybe they can't write because they have nothing like paper and ink.

Also alien psychology could be so different from ours that we can't guess what they would do. In other words, maybe they don't see the point in trying to contact other species so they don't.

I'm like Jesus, only better.
Democracy Now! - your daily, uncensored, corporate-free grassroots news hour

Why we haven't heard from aliens (and might never) (4.54 / 11) (#44)
by godix on Tue Jan 21, 2003 at 08:25:16 PM EST

  1. It probably won't happen by random chance. Given that interstellar travel is measured in 10's of thousands of years (at best) what are the odds that any race will visit even a slight % of stars in the universe, much less the one we happen to be at?
  2. Since it probably wouldn't be an accidental visit that means we'd only have visitors if they detected our radiowaves. That means that only races within 100 lightyears of earth would know we existed. Only those within 50 lightyears would have a chance to detect us, reply to us, AND have us recieve their reply. This reduces the chances of meeting aliens from 'any star in the universe' to 'the handful around us'.
  3. Lets say we're sitting here in the Milky Way and the nearest alien species is over in Andromeda. Do you think we'd notice one star in Andromeda producing double the radio waves it should? What are the odds we've even be recieving those radio waves yet?
  4. If we limit ourselves to the milky way, we're still pretty much out in the boondocks. An alien coming way out to our spiral arm to look for life would be like someone driving around the North Pole looking for some exciting Canadian night clubs. There is a lot better chance of success elsewhere, why look in the boonies?
  5. It's probably fairly safe to say that aliens would limit their search to 'life supporting' stars. It's a logical decision, and any race advanced enough to have space travel must have some form of logic, even if you resist the urge to anthromorphise them. Suppose our aliens evolved around a red dwarf. Whoops, by searching for 'life supporting' stars they've just eliminated us. The same arguement holds true for SETI and the like limiting themselves to yellow stars.
  6. Radiowaves are inefficient. We've only had them 100 years or so and we're already discovered that. I've heard fairly plausable arguements that mankinds technology will shift from radio waves to broadband optical communications and targetted energy beams, both of which are very difficult to accidently pick up. Especially if you're several light years away. That changes the task from trying to detect an advanced alien race to trying to detect an advanced alien race in the couple hundred years before they become all that advanced. Considering the time periods involved in the universe, catching something in that couple hundred years it goes on is highly unlikely.

Getting an education was a bit like a communicable sexual disease. It made you unsuitable for a lot of jobs and then you had the urge to pass it on.

We ARE in the boonies (none / 0) (#120)
by spacebrain on Sat Jan 25, 2003 at 12:26:18 PM EST

# If we limit ourselves to the milky way, we're still pretty much out in the boondocks. An alien coming way out to our spiral arm to look for life would be like someone driving around the North Pole looking for some exciting Canadian night clubs. There is a lot better chance of success elsewhere, why look in the boonies?

The opposite is the case: Life as we know it is resticted to an area about some 2/3 of the radius of a spiral galaxy - that's where we happen to live in. Closer to the center there are too many stars so that no stable planetary systems can exist, because of gravitational disturbances of their orbits. Farther away the concentration of heavy elements required for life is too small.

[ Parent ]

Qualification (none / 0) (#122)
by godix on Sun Jan 26, 2003 at 04:13:46 AM EST

"Life as we know it...."

Of course, life as we know it is restricted to the planet earth. I thought the entire point of looking for aliens is to find life that we don't already know about. Life as we don't know it might not live by the same rules of requiring planets or needed as many heavy elements as we do.

Getting an education was a bit like a communicable sexual disease. It made you unsuitable for a lot of jobs and then you had the urge to pass it on.

[ Parent ]

Ever try to commune with an ant colony? (4.14 / 7) (#49)
by StephenThompson on Tue Jan 21, 2003 at 09:17:13 PM EST

To any alien civilization, humans are just another part of the natural environment. If they were really perceptive they might think of us the same we we think of ants. When was the last time you went out and layed a chemical trail for ants read? Ant communication is quite bizarre by our standards, even though they are terrestrial social beings based on DNA. Yet we don't go out of our way to talk to them. Anything humans have done with them is, to the ants, indistinguishable from anal probes and cattle mutilations. The fact is humans are not worth talking to; we don't bring anything to the table.

I talk to ants (none / 0) (#83)
by ryochiji on Wed Jan 22, 2003 at 03:28:04 PM EST

...but they don't talk back.  And unfortunately, they run SECA@home (SECA: Search for Extra-Colonial Ants) which doesn't detect humans.

IlohaMail: Webmail that works.
[ Parent ]
But that is not the actual implied question (none / 0) (#84)
by gmol on Wed Jan 22, 2003 at 03:34:59 PM EST

I think when we ask about "life" exisiting on other planets and why it hasn't visited us, we have to read deeper into the question in order to understand what, IMHO, most people are actually asking.

A fair and sensible notion of life that covers just about anything that we may expect to find would be a relatively complex system, that can be understood (at least to first order) by chemistry.  The openeness as to what kinds of chemistry and at what scales, gives the definition of enough slack to cover just about anything that we could rationally search for.
Note that I don't feel that self-replication is a nessecary aspect of a chemical system that we could concievably call "alive".

But what we are really interested in when we ask about life is that, in addition to chemistry, is there is anything truly "universal" about human conciousness, thought and civilization.  Do similar chemistries happening in different places ultimately give rise to things like governments, cheese-burgers and space shuttles?  If there were, they would certainly eventally try to find each other...

Your comparison with ants implies only the search for complex chemistries; what we are really searching for are universal outcomes of those chemistries which we can directly relate to.

[ Parent ]

Simple logic. (3.50 / 2) (#54)
by mindstrm on Tue Jan 21, 2003 at 09:41:04 PM EST

We don't KNOW what the conditions are that cause life to happen.. because we have no other examples in the universe, yet, other than our own planet. Given that, any assumptions we make about how "common" life is are wild guesses at best.

Yes, obviously life such as we know could only happen on a planet similar in conditions to ours... but even that is based on a complete assumption.. that life could arise in the first place given those conditions.

It's not paradox. Until we find other life, we can't make any judgements.

The evidence from Mars (none / 0) (#57)
by arvindn on Tue Jan 21, 2003 at 10:07:39 PM EST

It is generally considered that a couple of billion years ago there were primitive organisms on Mars (perhaps as primitive as earth viruses, but still living). There is some direct evidence, like traces of life in meteorites of Martian origin, and some circumstantial, such as the abundance of ice. Considering that some form of life existed in two out of nine planets that can be observed, chances are that it arose in an enormous number of planets outside earth. Intelligent life is another question, of course.

So you think your vocabulary's good?
[ Parent ]
that assumes (none / 0) (#68)
by tichy on Wed Jan 22, 2003 at 05:23:12 AM EST

that the origin of mars' and earth's life is not the same. Why, someone as respected as Crick believes life did not originate here on earth... but instead came from space.

[ Parent ]
Life has certain requirements (none / 0) (#98)
by Eater on Thu Jan 23, 2003 at 07:29:02 PM EST

For chemically-based life (that is, life that "lives" through chemical reactions) to evolve, there have to be chemicals that are capable of doing lots of fancy reactions in a reasonable amount of time. Carbon is very good for such purposes, and many other, more common elements are not. That doesn't no life can ever evolve without carbon, but the presence of carbon makes life much more likely to appear (in theory anyway). Eater.

[ Parent ]
You have meet aliens... (1.00 / 4) (#65)
by johwsun on Wed Jan 22, 2003 at 03:10:59 AM EST

..nice to meet you!

Dual Supernovae (3.33 / 3) (#75)
by Eight Star on Wed Jan 22, 2003 at 12:08:51 PM EST

Perhaps this is what happens when civilizations meet.

Time. (3.50 / 2) (#77)
by pla on Wed Jan 22, 2003 at 01:08:28 PM EST

Based on the age of the universe, and the natural evolution of stars, we exist as one of the first *POSSIBLE* carbon-based lifeforms in the universe.

The limiting factor here involves the very presence of carbon.

A star produces carbon by nucleosynthesis when it runs out of hydrogen and starts "burning" helium. Too small of a star (and too long lived anyway, these still haven't even passed one generation) won't have the pressure needed to start helium fusion. Too large of a star (which live and die rapidly enough to have passed quite a few generations) will fuse all that nice new carbon into neon (and possibly eventually reaching iron, the ultimate stellar ash, in stars above 25 times the size of our own sun). A star that will produce carbon lives for around 6-8 billion years (slightly shorter than our own star, which will probably not go past helium burning).

So, basically, we need at least one complete life cycle of a star slightly heavier than our own. Although we may not know the exact age of the universe, the oldest stars we can find have lived for 12.5 billion years. This sets an upper limit (at least for our neighborhood, in which we clearly did come into existance) for the number of generations of stars that could have lived, died, formed a nebula, and reformed into other stars who's accretion disks contain carbon. Namely, exactly one and a half.

So why do we not see anyone else in the universe?

Because we got here first. Others may exist *with* us, but they most likely don't have any great head start on us. And, we may well have gotten here first, doomed to die in isolation millions or even billions of years before any other life arises in this galaxy. How depressing.

Of course, we may take some comfort from the fact that, as soon as the universe had satisfied the physical conditions required for us to exist, we popped up. That does tend to lend support to the idea that life may well exist just about everywhere it can, not just on Earth from some magical combination of circumstances.

Incomplete logic (none / 0) (#79)
by wurp on Wed Jan 22, 2003 at 01:39:54 PM EST

So you're saying that enough carbon has been around for over 6 billion years, but no civilization is the few thousand years ahead of us that might be required for it to have already colonized the galaxy?

That seems a pretty far stretch, unless you throw in the logic the article author is using (the only groups around to ask the question are the ones that are in a situation so that they haven't already encountered aliens).  And if you use that logic, you don't need your logic except to explain part of the reason we might be such a group.  Even then, given the timescales, it seems a pretty weak argument to me.
Buy my stuff
[ Parent ]

Radio Assumptions (4.33 / 3) (#88)
by thesik on Wed Jan 22, 2003 at 09:02:55 PM EST

Many comments here talk about radio communications being a telltale sign of another civilisation and yet the period when a civilisation emits detectable amounts of radio waves is probably very short, perhaps just a couple of hundred years.

We've already progressed to using Satellite and Cable systems for much of our communication and we're using increasingly low-powered radio for personal communications such as Wi-Fi, Bluetooth, etc.

It seems likely that in 50 years we will have ceased to broadcast radio and TV signals as that spectrum will be simply too valuable and will be needed for low-powered Wi-Fi type communications. All audiovisual entertainment will be received by either Satellite or Cable.

It may even be that almost all our communications become optical or that we discover some new method of communicating over long distances, the physics of which we can only guess at today.

It seems reasonable to assume therefore that the period where any civilisation emits detectable quantities of radio waves may only be of the order of 200 years or so. Blink and you've missed it.

There may be thousands of civilisations out there but they have either not started communicating by radio yet or they have moved on to more efficient methods of communication. We have to hope that we get lucky and catch that brief spurt of radio traffic from one of them.

Current radio technology is quite restricted. (none / 0) (#136)
by jjhlk on Sat Mar 15, 2003 at 12:16:05 AM EST

(In retrospect this is messily written, just bear with it)

This is from something I read on my PDA the other day. I believe the article was at Salon.com (AvantGo version however). It was a long interview with a [computer] (I presume) scientist who was quite annoyed at how our radio systems work.

Currently, the FCC restricts usage of frequencies and makes sure that stations don't use each others frequencies, etc... But this is all from the fact that we are still using old analog radios that can only hone into signals if there are spread apart enough, otherwise multiple signals will interfere. That is only because we are taking a sound, changing it into an electromagnetic wave that bears some similarity to the sound (because it isn't digital), and then the radio undoes the process.

The scientist in the article looked at the radio network as being potentially another internet style network. In fact, it could just be linked to the old internet, but as one huge wireless network. Because what is the difference between the wires connected the current internet and the radio waves? They are both electromagnetic waves, just on a different medium.

The fact is, there is no need to spread out signals for old radio receivers. Quantum mechanics (apparantly) states that two waves could exist on the same frequency. The way to differentiate between them would be by seeing how they are encoded. Software driven radios ought to be in the future at some point.

So rather than a civilisation going: Radio->Better-unsimilar-technologies, it might instead be: Analog-Radio->Digital-Radio.

Maybe we've picked up alien digital signals and passed it off as star-noise already...

[ Parent ]
simple answer (1.62 / 8) (#89)
by brandon21m on Wed Jan 22, 2003 at 09:28:21 PM EST

God created 1 Earth. We are the only "intelligent" life, albeit immoral as all get out. There are no "aliens". Only 1 species has souls and thats humans. Get over it.

Being as most of us aren't close minded christians (4.50 / 2) (#90)
by synik on Thu Jan 23, 2003 at 08:05:28 AM EST

we'll ignore that comment.

Try detaching yourself from religion for a why and consider the scientific view point.

Besides, who's to say aliens don't exist? I don't remember the bible saying so.

The human race has suffered for centuries and is still suffering from the mental disorder known as religion, and atheism is the only physician that will be able to effect a permanent cure. -- Joseph Lewis
[ Parent ]

Yeah (none / 0) (#99)
by TheOnlyCoolTim on Thu Jan 23, 2003 at 07:29:34 PM EST

I actually have the word of a Catholic priest that belief in aliens doesn't go against God. Of course the parent poster probably believes the Papists are just as bad as the money-loving Jews and the terrorist Muslims.

"We are trapped in the belly of this horrible machine, and the machine is bleeding to death."
[ Parent ]

Who said that they do? (2.66 / 3) (#108)
by tkatchev on Fri Jan 24, 2003 at 07:17:17 AM EST

Empirical science and 10000 years of human experience say that they don't exist.

So, dude, you lose. Go back to your cave where you worship your flying saucers.

   -- Signed, Lev Andropoff, cosmonaut.
[ Parent ]

heh (none / 0) (#112)
by adequate nathan on Fri Jan 24, 2003 at 02:06:20 PM EST

Try detaching yourself from religion for a why and consider the scientific view point.

You know, materialistic naturalism is not accepted by any philosopher of any significance, and The Golden Bough was written eighty years ago. For a progressive, you sure do live in the past a lot...

"For me -- ugghhh, arrgghh."
-Canadian Prime Minister Jean Chrétien, in Frank magazine, Jan. 20th 2003

Join the petition: Rusty! Make dumped stories & discussion public!
[ Parent ]

Yeah. (none / 0) (#121)
by tkatchev on Sat Jan 25, 2003 at 04:56:07 PM EST

Personally, I believe that Frazer should be lumped together in the same pile with Lovecraft.

(Not meant to be denigrating -- personally, I love Lovecraft, but only as a cute example of "trash aesthetic".)

   -- Signed, Lev Andropoff, cosmonaut.
[ Parent ]

Troll/Genuine christian(aka fucking idiot) ! (none / 0) (#97)
by ThreadSafe on Thu Jan 23, 2003 at 06:41:52 PM EST

nuff said

Make a clone of me. And fucking listen to it! - Faik
[ Parent ]

Get over christianity (none / 0) (#102)
by Rainy on Thu Jan 23, 2003 at 09:33:19 PM EST

Rainy "Collect all zero" Day
[ Parent ]
Re: Get over stupidity. (none / 0) (#107)
by tkatchev on Fri Jan 24, 2003 at 07:15:03 AM EST

Use that oft-touted "open" mind of yours, retard.

   -- Signed, Lev Andropoff, cosmonaut.
[ Parent ]

Fermi Paradox is Flawed (2.00 / 2) (#91)
by NuWinter on Thu Jan 23, 2003 at 08:45:40 AM EST

It seems to me that the entire subject of other Civilizations in Space and Human Exploration of the Universe within that context suffers from a tragically miniscule capacity to see what is apparent to anyone who takes the time to see it, which is primarily that the Fermi Paradox is fundamentally flawed in that there is no use asking where EI is, as there are multiple civilizations in our solar system already.

So ET is already here. No, not in City sized ID4 ships but in smaller "reconnaissance" vessels or "tourist" craft. Then from this fact It doesn't take a great leap of thought to go from, the strange lights that move around with great swiftness at 90 degree angles and shoot off into space and in some cases simply vanishing visually and from radar when approached by Military Aircraft, to the acknowledgement of other Civilizations actually visiting us for their own purposes (whatever those might be).

Don't accept this? Well would you take the word of Government Employees and military pilots who have recorded "craft" (on radar regularly) doing just as I have stated? No? Then would you accept the statements of astronauts who have stated that they as well have seen metallic craft around the earth and the moon (during the Apollo missions)?

Now some of you may have seen on Slashdot what was recently posted about The SOHO satellite recording "UFO like" craft with its camera, now over the guffaws from most, what was probably missed was the fact that there just weren't a few little multicolored blobs photographed, there were "hundreds" of "UFO like" Craft recorded, and these "UFO like" craft ranged from the typical flying saucer shaped craft that we all see to (I'm not joking) Enterprise and Klingon looking vessels. This information can all be see at this link where if you can sit through the introductory stuff you'll see the highly interesting craft that have been photographed and can't or won't be explained by NASA (and make no mistake about they will not explain them and it has nothing to do with anger or fatigue with the questions).

Also not only were craft photographed by SOHO but there are movies of the craft seen doing exactly what they do on Earth, flying around at incredibly fast speeds and even in some cases going towards the Sun's corona to perhaps recharge their batters (Rendezvous with RAMA readers will recognize this).

As you wipe the tears from your eyes from laughing remember than that not only have military officials recorded these Craft, but also civilian airport officials, pilots, and astronauts, not to mention thousands of very sane, non delusional, and reasonable people. They don't make such things up. They can't even imagine sacrificing everything in their career just to get front page treatment on the National Enquirer. It doesn't make any sense. They've been harassed, fired, abused, and in some cases even killed for their trouble to report the truth. Don't believe it? Try reading The Disclosure Project sometime.

Therefore, Assuming the statements above are true there are a few things that must be accepted. 1. Interstellar travel is attainable within a reasonable period of time (a human lifetime or possibly much much sooner). 2. There are an awful lot of ET Craft out there, implying that either its one civilization's craft (doubtful) or its an entire galaxies worth of travelers ala Star Wars. The latter is much more probable. 3. Whoever is out there doesn't wish to make themselves known (not officially to all earthlings anyway) yet. 4. FTL travel is more than likely attainable since we haven't seen any ET bases near our planet and must conclude that most of these craft seen come from other solar systems.

But none of this makes any sense right? How or Why would other civilizations simply ignore us and go about their business in our solar system? Well seeing as how they are highly advanced technologically it's a fair guess that they have seen and recorded most if not all of our radio and TV transmissions, which is to say they've seen ET, ID4, Close Encounters, etc..And if they've been around here for thousands to maybe hundreds of thousands of years then they know all about human society and what it does when it meets strangers. So the questions then becomes not Why would they ignore us but why would they even let us see them. Then as to the How they evade us well, they let us see them visually and I'm more than positive we've recorded their EM transmissions we just see them as noise (think UWB on steroids for Interstellar Civilizations), so that's not really an issue.

Finally then I think it more comes down to why haven't they formally introduced themselves to us yet. Well, try and see it from their perspective if you were a technical civilization that had advanced technology for thousands to maybe hundreds of thousands of years would you show yourselves formally to a group of beings barely out of the stone age (relative to their time)? What will more than likely happen is as we go out into space ourselves it will force them to acknowledge us (think a recently industrialized Japan during the Late 19th Century) and introduce us to the Galactic Confederation (or something like it) and tell us the rules and regulations of a developing civilization (think Preschool mixed with the UN).

I don't think they will welcome us with open arms, a more likely possibility is a stern introduction to the rules of civilized conduct and being told what weapons we can and cannot possess and where we can and cannot go (think Iraqi no fly zones only hopefully without the frequent bombing). But it won't be all bad, I'm sure they'll give us some technology to help us go around the galaxy, just not enough to hurt ourselves or others.

relevant website (none / 0) (#100)
by dollyknot on Thu Jan 23, 2003 at 07:32:46 PM EST

I have written a thesis based on the anthropic principles and chaos theory, you can read it here.

They call it an elephant's trunk, whereas it is in fact an elephant's nose - a nose by any other name would smell as sweetly.

Good god man! (none / 0) (#103)
by StephenThompson on Thu Jan 23, 2003 at 09:51:06 PM EST

Are you color-blind?

[ Parent ]
If you mean me, no - why? (none / 0) (#111)
by dollyknot on Fri Jan 24, 2003 at 10:50:05 AM EST

They call it an elephant's trunk, whereas it is in fact an elephant's nose - a nose by any other name would smell as sweetly.
[ Parent ]
I was about to give it a shot... (none / 0) (#109)
by floydian on Fri Jan 24, 2003 at 08:33:09 AM EST

but you misspelled "principle" as "PRINCIPAL", right there in your Thesis the First! Sorry man, but that threw me off right from the start.

[ Parent ]
Heh (none / 0) (#110)
by dollyknot on Fri Jan 24, 2003 at 09:10:06 AM EST

Thanks a million. Pete.
They call it an elephant's trunk, whereas it is in fact an elephant's nose - a nose by any other name would smell as sweetly.
[ Parent ]
Pete? (n/t) (none / 0) (#113)
by floydian on Fri Jan 24, 2003 at 03:54:44 PM EST

[ Parent ]
Yes (none / 0) (#114)
by dollyknot on Fri Jan 24, 2003 at 05:56:06 PM EST

They call it an elephant's trunk, whereas it is in fact an elephant's nose - a nose by any other name would smell as sweetly.
[ Parent ]
no (none / 0) (#116)
by dollyknot on Sat Jan 25, 2003 at 12:00:13 AM EST

They call it an elephant's trunk, whereas it is in fact an elephant's nose - a nose by any other name would smell as sweetly.
[ Parent ]
Anthropic principle inapplicable (5.00 / 10) (#101)
by riptalon on Thu Jan 23, 2003 at 07:51:23 PM EST

If the Fermi paradox is valid, I am not convinced that you can use an anthropic principle to wriggle out of it. When you are talking about cosmological parameters it is simply a matter of "if they were not close to their observed values then we would not be here to observe them". However in the case of alien intelligence you have to put in the assumption that it exists, a priori, before you can then use an anthropic principle to explain why we haven't seen it yet. But in reality there is the alternate possibility that alien intelligence does not exist, which invalidates the anthropic principle. An anthropic principle is based on the fact that if something we observe wasn't as we observe it, then we couldn't be here to observe it. Therefore it has to be the way we observe it. But in the case of alien intelligence there is an option, that alien intelligence does not exist, that explains the observations perfectly. Therefore an anthropic principle cannot apply.

This being said I am far from convinced that the Fermi paradox is valid. The Fermi paradox makes a huge number of assumptions about how "aliens" will behave that will not necessarily be true. Basically it is assumes that they will be motivated in similar ways to humans. Unless the range of "alien" behaviors is fairly small and humans are very average, within that range, it seems unlikely that the Fermi paradox is a valid argument. The paradox also implicitly assumes things about future human development that may be just wishful thinking. It is far from clear to me that if we don't destroy ourselves, humans will go on to do what the Fermi paradox assumes alien civilizations will do. In terms of behavior the Fermi paradox assumes that any alien civilization will be driven either to expand and colonize every planet they can get their hands on, or else to endlessly search the universe contacting every other alien civilization they find. In either case we would then expect to have had some contact by now.

What are our reasons for believing that an alien civilization would be driven to expand and colonize other planets without limit? Obviously this idea comes from observing the history of humans on Earth, which has been marked waves of expansion into new areas throughout history. However we have to ask what the reasons for this expansion were before we can decide whether it might be generally applicable to alien civilizations. The answer to this question is competition, which today is embodied in modern capitalism. The capitalist economic system has a built in need for expansion and in fact cannot exist without it. While alien civilizations might have many reasons for expansion that we could not possibly guess at, the major reason for which we have any direct experience to draw on, is if they functioned under an economic system similar to capitalism. The question then becomes how likely is it that a significant fraction of alien civilizations have capitalist like economic systems that demand expansion. This is a surprisingly easy question to answer if you consider the fundamental nature of capitalist economics.

The driving force behind economic expansion today is encapsulated in the equation for compound interest:


where P is the initial deposit, r is the interest rate, t the time, n is the number of times per time unit the interest in calculated and S is the final amount accrued. By playing with this equation it is possible to show that if you deposited one pence/cent in a bank two thousand years ago, at an interest rate of 5 percent, you would by now have accrued an amount much greater than the cost of a solar mass of gold. This clearly demonstrates that the exponential growth demanded by capitalism is unsustainable over the long run. This can be even more clearly seen on the galactic scale. If we consider an alien civilization which has the wealth of one solar system at its disposal, then in two thousand years it will need to colonize 10^21 times all the solar systems in the observable universe, in order to sustain the economic growth needed to pay a 5 percent interest rate to investors.

Even if you drop the interest rate to 1 percent (not the sort of return any capitalist will accept), that only buys you ten thousand years (rather than two thousand) to colonies 10^21 times the observable universe (I am using the fiducial number of 100 billion galaxies with 100 billion stars each for the observable universe). A comparison of ten thousand years with the light travel time to the edge of the observable universe (approx. 14 billion years) clearly shows that, even if some way is found to bypass the limit of the speed of light, capitalism is not going to fly as an economic system of an alien civilization in the long run. At some point in the development of any civilization they will find that the exponential growth rate demanded by capitalism cannot possibly be sustained by their available resources. This might happen at a planetary level, a point humanity is approaching now, or that might be avoided by expanding to fill the whole solar system, but once you get that far you are faced with a huge gulf to cross to reach the nearest stars. While expansion is still possible, it is never going to be fast enough to sustain a capitalist economy.

Clearly at present since capitalism sort of "works", an exponential economic expansion is taking place. However this has only been happening for the last few hundred years and is not a global phenomenon. This rate of expansion cannot continue indefinitely as we have seen it would necessitate access to more resources than available in the entire universe within a thousand years or so. This temporary exponential expansion has been allowed by a number of factors. Firstly advances in technology have allowed access to more resources and more efficient use of existing resources. However future technological advances will produce diminishing returns as efficiencies approach theoretical limits and the fraction of inaccessible resources decreases. Secondly the expansion has taken place only among a subset of humanity through war and imperialism, one group is expanding at the expense of other. Obviously this cannot continue indefinitely since soon there will be no one left to steal from. Thirdly non-renewable resources such as oil are begin use which will soon run out. All these factors are transitory and will eventually disappear and with them the exponential economic expansion.

It therefore seems likely that either at the planetary or solar system stage any alien civilization that is going to survive long term will have to adopt an economic system that does not demand exponential growth. Removing the economic drive for expansion and colonization does not mean that it will not happen. A civilization based around a small group of adjacent stars will be much more robust than one on a single planet or indeed a single solar system. But without a strong economic drive to expand, given the amount of time needed for interstellar travel there would be little motivation to try and colonize a whole galaxy. A related point is the questionable desirability of going anywhere near planets, from an economic perspective. Planets sit at the bottom of large gravitational wells and it takes a large amount of energy to raise material off the surface of a planet. Once you move off your home planet the most attractive source of raw materials is not other planets, but asteroids and comets where the retrieval of the material requires much less energy. Also heavy elements (metals) are much more plentiful on asteroids than on planets, since planets have been melted and most of the heavy elements have sunk into the core, where they are inaccessible.

An advanced civilization is therefore unlikely to be particularly interested in planets from an economic perspective, since anything they want can be obtained from smaller bodies with less expenditure of energy. A space fairing civilization is ultimately likely to become space based, living in spacecraft and other large space structures (like the Culture), since that is where all the easily obtainable resources are. This provides many other advantages such as insulation from the vagaries of a natural biosphere and mobility in case of local problems (comet/asteroid impacts etc.). Such a civilization might slowly drift between the stars with time, but would not expand far from its point of origin and even if one was nearby and had visited our solar system in the past, it would probably have only trawled through the Kuiper belt, scattered disk and Oort cloud looking for raw materials and is unlikely to have payed much attention to the inner solar system. From an economic perspective there seems little that would drive an other civilization into contact with us.

The other major pressure that might drive another civilization into contact with us is curiosity, the quest for knowledge. However this is actually quite a weak argument for loads of advanced civilizations turning up on our doorstep. After all by definition they are the ones with all the knowledge, and we are extremely poor by comparison. This is not to say that a civilization might not be extremely curious about alien lifeforms when it first left its home planet, but the returns in terms of extra knowledge gained, with each new life baring planet explored fall off pretty quickly. When you have only one biosphere to study, finding another is a big deal, but after you have explored a thousand biospheres, and may be contacted a few intelligent species, your can pretty well infer what the rest of the universe is like from statistics. Also as your civilization evolves the level of intelligence necessary to be interesting is likely to evolve upward as well. Any civilization that continues to explore planets as cataloging exercise after they are fully conversant in astrobiology and alien sociology, are only going to linger over really interesting finds. Their take on Earth is probably going to be along the lines of "more primitive bipeds with nuclear weapons, next".

The lack of "credible" observations of aliens does not necessarily mean that the solar system has not been visited by aliens many times in its history. But scientific visits are unlikely to leave any trace evidence at all and any evidence of resource gathering (mining) is likely to be confined to the far outer solar system, most likely beyond Neptune, where at present it is inaccessible to us. In fact it is likely that we would be oblivious to either scientific observation or resource gathering if it was going on today. Given that we have only found a fraction of the asteroids greater that a kilometer in size, it would be possible for some sizable spacecraft to wander through the solar system without us noticing. The assumption implicit in the Fermi paradox that just because some aliens past through the solar system they would bother to try and communicate with us, is vane to say the least. We see ourselves as special but to a certain extent the more common life is in the universe the less interesting any advanced civilization will find us, since they will have seen loads of creatures very similar to us before.

There is also the point that it is far from clear that humans are set to rush out and explore the galaxy looking for aliens, so why should we expect aliens to do the same. Humans landed on the moon over thirty years ago but they did nothing once they got there and since then space exploration has been going backward rather than forward. While there may be a small minority that is extremely interested in space travel, under the present system it is unlikely that significant progress will be allowed until there is immediate economic benefit to be gained from it. Space travel poises some difficult control problems for our present hierarchical society and unlike similar problems on Earth that have been solved with advances in technology, these seem fundamentally intractable with our present understanding of physics. While space exploration seems stalled at present, and it is in the interests of the elite to keep it that way, computers, robotics, nanotechnology, biotechnology etc. seems set to fundamentally alter human society in the coming century. It is far from clear where this will lead but it is also far from clear that humans will ever be allowed to leave Earth in any numbers.

Your point is correct, but... (none / 0) (#123)
by cbraga on Sun Jan 26, 2003 at 11:30:22 AM EST

...the fact that exponential growth isn't sustainable indefinitely doesn't mean a civilization won't try to sustain it until it cracks.

ESC[78;89;13p ESC[110;121;13p
[ Parent ]
True, but ... (none / 0) (#129)
by riptalon on Tue Jan 28, 2003 at 08:08:09 PM EST

This may very well be true in many cases but whether a civilization destroys itself trying to make capitalism work or is forced to change to a sustainable economic system, the end effect is the same. They will not end up expanding through the universe and so will not be forced into contact with us by economics. The crisis point for capitalism will occur very early on at a planetary scale, or possibly at a solar system scale, but by the time significant interstellar travel is possible a civilization that has survived will have already been forced into an economic system that demands little or no growth.

Of course this all presupposes that an alien civilization would have developed capitalism in the first place. Since we have only one example to study the probability of this is very uncertain. It is somewhat analogous to the problem of predicting of alien physiology. However since there are a huge number of species on Earth, you can make a stab at the physiology problem, where as with only one intelligent species alien economics is a lot harder. For instance you can look at particular evolutionary adaptions that have happened many separate times on Earth, such as wings (birds, bats, insects, flying fish etc.), and say they are likely to occur on another planet if the conditions are similar.

[ Parent ]
Very interesting... (none / 0) (#127)
by max3000 on Mon Jan 27, 2003 at 03:51:33 PM EST

... do you have a site or paper that formally discuss this?

BTW, you might want to send this to capitalism.org. They apparently have a very strong opinion about anyone opposed to capitalism. All intellectuals in particular... ;)

I fell upon the following FAQ doing some browsing.

(From http://www.capitalism.org/faq/intellectuals.htm)

"Why is capitalism so despised, maligned, and misrepresented by the intellectuals in our universities?

The intellectuals despise Capitalism because it is completely in opposition to their basic, philosophical principles.

Capitalism is the system of individual rights; the intellectuals on all sides are for some form of collectivism. Capitalism is the system of individualism, self-interest and happiness; the intellectuals are for altruism, self-sacrifice, and misery. Capitalism is pro-reason; the intellectuals are steeped in mysticism and subjectivism. Capitalism is is a social system for living in reality; a reality which the intellectuals despise, or whose existence they deny.

No wonder the bulk of the intellectuals who infect today's universities are against Capitalism -- it represents the antithesis of everything they stand for. How could they not be?

Suggested Reading: See Leonard Peikoff's Objectivism: The Philosophy of Ayn Rand on the relation between philosophy and economics in the chapter on Capitalism."


[ Parent ]

Criticisms of capitalism (none / 0) (#128)
by riptalon on Tue Jan 28, 2003 at 07:42:15 PM EST

Unfortunately, but perhaps unsurprisingly, there seems to be very little literature on this subject. The fact that capitalism demands exponential growth is mentioned in passing by some environmentalists, to whom it is obviously an important effect. But since environmentalist tend to have a fairly narrow outlook they do not take the argument to its logical conclusion, that capitalism would need to colonize the whole universe (at much greater than the speed of light) just to sustain itself for the next thousand years or so. This is obviously far more damning than saying that capitalism is going to destroy the planet in order to maintain its needed growth, since there is no possible way to get around it. Where as for an environmental catastrophe on Earth you can always can always invoke colonization of the solar system to avoid it.

As well as the this unsustainability argument, which I personally think is extremely compelling by itself, capitalism can also be attacked from a purely scientific perspective on the grounds of instability. It is fairly easy to demonstrate that the business cycle, an alternating series of booms and depressions, is an inherent feature of the capitalist system rather than being the result of our system not being capitalist enough, as most economists claim. I think it is pretty difficult to argue that this instability can considered to be a positive feature of capitalism, although I expect that your could find some economists that would try. So before you get down to the also very strong arguments about exploitation and oppression, capitalism is already on a very weak scientific foundation.

As far as I can see modern economics has much more in common with voodoo and astrology than it does with even the most wishy-washy social science. In some ways the development of economics can be compared to that of statistics. The first real statistical theory, "Bayesian Statistics", was close to perfect in its description of reality. However the reality, that in order to correctly calculate the probability of some theory being true you needed to include all the existing relevant information not just the results of your latest experiment, was judged rather inconvenient by most people at the time. Therefore "Frequentist Statistics" was born, which through various convoluted means, like not allowing probabilities to be attached to hypothesis's only to data, removes the need to think about prior probabilities. Of course what you really want to know is not how probable your data is, given a certain theory, but how probable a theory is given the available data. But in wriggling out of the need to consider all the data you also lose some of the power of Bayesian statistics.

In a similar way the first scientific economic theories were not particularly bad descriptions of reality, but in this case the reality was not just inconvenient but at total odds with the "reality" capitalists wanted to portray. The modifications necessary to bring the theory in line with this "reality" were therefore much more extreme and the resulting theory is not just less powerful, as with Frequentist statistics, but just plain rubbish. Not only does it not make very many useful predictions, but its assumptions are generally contradicted by all the available evidence. However this is not a problem since the raison d'tre of modern economics is to provide a convenient justification for the continuation of capitalism, rather than to provide any predictions on how the economy will behave or how it can best be managed.

Capitalism is more like a religion than a science, although it tries hard to dress itself in scientific clothes. For this reason arguing with its fanatical adherents is generally a waste of time. They believe and are therefore not going to be swayed by any amount of evidence or logic. Obviously there is something to be said for indulging it arguments purely to exercise your own logical skills and force yourself to work through a problem in detail. However I think the quality of counter argument you would get in a forum such as this would be higher than in one where most people are religious in there views, plus you have the added bonus that there is some possibility you might actually change someone's mind.

It is a sure sign of a religious mentality when people attack the proponents of an argument rather than the logic of the argument itself, as with this "all intellectuals are anti-capitalist" diatribe. Not to mention that it just isn't true. Most intellectuals have been indoctrinated with capitalism as children, just like everyone else, and never examine those beliefs closely enough to see what a weak foundation they are based on. It is just that the few "intellectuals" that do look closely and challenge those beliefs have a by definition a platform to express their views, where as the "non-intellectuals" that do the same are not going to get much exposure and can therefore be ignored.

A very good, though long, criticism of capitalism is presented here, although it does not contain the unsustainability argument.

[ Parent ]
Sounds like Malthus (none / 0) (#130)
by BCoates on Thu Jan 30, 2003 at 02:59:22 PM EST

If I understand what you're saying, it sounds vaey similar to the argument of Thomas Malthus, that consumption tends to grow exponentially and resources do not; his particular point was that population grows exponentially and food supply grows linearly.  Of course Malthus didn't condsider the option of colinizing other planets, but you are quite correct that it doesn't really change things.

There are, indeed people who claim that the business cycle is a feature and not a bug; the argument is that cyclical systems are often more robust than a stable balance.  Robustness of capitalism being a good thing or a bad thing depending on your outlook, I suppose.

It's worth noting that at least so far, Malthus was only half-right, and despite human population growing as expected, no great global famine occured, instead there is more food per person now than probably ever.

Benjamin Coates

[ Parent ]

PS to my post below (none / 0) (#131)
by BCoates on Thu Jan 30, 2003 at 03:05:03 PM EST

An Essay on the Principle of Population

[ Parent ]
Correction regarding 'capitalism'. (4.00 / 1) (#137)
by alexboko on Sun Mar 16, 2003 at 06:31:51 PM EST

You raise some interesting points regarding the economics of a starfaring society, particularly with regards to inner-system regions not being much of an attractive prize. However, there are a few issues about capitalism that I feel compelled to clear up.
  1. You assume that there is some kind of minimum interest rate below which capitalism will collapse. That is not the case-- in a free market economy, investments that give the highest payoff will be favored (until, in theory, the risk-benefit ratio for any investment is the same). If the best rate of return you can get is 0.05% or 5 x 10^-5%, that will be the investment you'll make. The 5% figure you mention would be considered absurdly optimistic by any investor before the late 1990's. I see no reason why an attractive rate of return won't decay asymptotically toward 0 forever. In other words, as long as there is the possibility of some sort of growth, however gradual, many of our current economic models will still hold.
  2. You are only taking physical matter into account when you talk about limits to growth. Increasingly, wealth = information, and behaves according to a different set of rules, which we are just starting to understand. One thing that is clear is that an information economy will have more positive sum characteristics than a physical economy.
  3. Fine, information economy blah blah blah, but people still need to eat, right? So that means availability of matter, space, and energy are still limiting factors on growth, right? Even if human do redesign themselves to use matter/space/energy more efficiently, there is still some sort of theoretical maximum on how much data you can cram into a volume of space, and therefore a continuing demand for more. I don't think this demand will go away just by restructuring the economy, because it ultimately stems from each individual's desire to survive as long as possible and reproduce (creating more individuals who will also all want to survive and reproduce). Individuals can of course override this drive, but the very act of doing so will minimize their influence on the overall behavior of the species. Therefore, while growth outward (capturing new resources) and inward (making more efficient use of existing resources) may not always continue to increase exponentially, it will continue at some rate as long as it is at all possible.
  4. The term 'Capitalism' can be misleading. You seem set it up as a hypothetical economic system that depends on exponential growth in order to be sustainable. American Heritage Dictionary defines it as "An economic system in which the means of production and distribution are privately or corporately owned and development is proportionate to the accumulation and reinvestment of profits gained in a free market." Whether or not either of these systems will continue to be viable in the very far future, I would like to point out that this doesn't imply that these hypothetical, highly advanced alien civilizations are run by central planning! Even now, governments are struggling to keep up with economies comprised of hundreds of millions to billions of individuals. They are repeatedly either voluntarily devolving some of the decision-making burden to free market mechanisms (China) or collapsing under their own weight (USSR). True, improvements in computing power and communications might have helped it linger a few decades more, but can you imagine any meaninful central planning being done on an economy comprised of trillions of individuals, possibly separated by relativistic distances? Whether we would consider economies of the future "Capitalist" or not, it's clear that they will evolve from decentralized, free-market, systems... simply for reasons of information theory.

Godwin's Law of video games: if a company is out of ideas for a long enough period, they will eventually publish another World War II shooter.
[ Parent ]
Meta correction (none / 0) (#138)
by riptalon on Wed Mar 19, 2003 at 06:56:04 PM EST

On the contary, there most definately is a minimum interest rate below which capitalism will collapse. If you look at an exponential curve you will notice that it starts off quite flat for an long time. Even a 5% per year increase doesn't do very much initially. The curve progressively steepens at an increasing rate however. An initial stake of 100 pounds/dollars will only get you 5 pounds/dollars a year initially, but if left to accrue for 50 years you will then be getting 60 pounds/dollars a year. Now 50 years would seem to be a close to maximum investment time. People invest in order that they can benefit in the future. Therefore investments lasting longer than the average human lifespan are pointless. A 5% interest rate turns 100 pounds/dollars into about 1200 pounds/dollars in 50 years, an increase of 12 times. The interest rate of 0.05% you suggest would turn 100 pounds/dollars into 102.5 pounds/dollars in 50 years (yet at the same time it demands you colonise the visible universe in about 100,000 years rather than a few thousand, still an impossiblity).

Now who is going to invest 100 pounds/dollars today in order to see 102.5 pounds/dollars in 50 years, when you might well be dead. While some increase in the human lifespan might be possible this doesn't really help since it also increases the amount of time into the future that the humans care about. If humans lived five thousand years they could see a 12 times increase in there investment over their lifetime for an interest rate of 0.05%. But in that case the 100,000 years they need to colonise the visible universe is no longer the far future for them. The shape of the exponential curve is what matters and scaling factors like the human lifespan are just details. For the steeply increasing portion of the curve to be far enough in the future that it can be ignored, the curve at the present time has to be so flat that no investment is worth it in a human lifetime.

Also you are forgetting that there in no mechanism to intellegently set the growth rate in capitalism anyway. The growth rate at any given time is forced towards its largest possible value at that particular time by competition. Therefore high growth will continue right up until a brick wall is hit and no resource expansion is possible. The economy will then collapse and contract, with the attendent human suffering, until it has enough breathing space to take off and start growing again. Of course after a year or two it will hit the resource limit again and the cycle will repeat. You will get a period of the economy throwing itself against the wall, picking itself up and doing it again. In the meantime a large amount of warfare could be expected as various people try to "buck the market" by gaining privilaged access to resources for themselves using force.

In the end however, if humanity didn't destroy itself in the process, a system that didn't demand significant growth to work would have to be adopted. Given that the decision on what system to adopt would be made by the ruling elite one would assume that a return to some sort of feudalism would be the most likely outcome. This would be a sort of corporate feudalism, where the corporation owned their workers/customers and "payed" them in food, housing etc. rather than money. Each corporation, if there was more than one, would be relatively self-contained and would not compete directly, since the "workers/customers" are bound to the corporation they are born into. Jobs would basically be hereditary with little interchange between workers and management.

This can be thought of as a sort of hybrid state/corportaion which was what existed before the advent of capitalism, when the economic and political spheres were separated. This separation had great benefits for the ruling elite in that it obscured the force inherent in the system making it appear like the workers had some choice about working for their capitalist masters. A return to feudalism would of course negate this advantage but if capitalism is crumbling around them, it would be in the best interests of the elite to make the change while they still held power rather than waiting until till the entire system desintegrated.

Once the ruling elite had installed itself in the top spots of this new corporate feudal order there is much they could do to ensure they remained there. Medieval feudalism was maintained by the fact that medieval weaponry was expensive and required a large amount of training. However the resulting armoured knights could then expect to best any number of ordinary peasants. The invention of firearms altered the balance since these weapons required virtually no training in comparison and were relatively cheap. However the present trend in weapons technology, and particularly the effect that robotics will have, suggests that balance desicively shift back to a small well armed elite during the 21st century.

You are right that a short term get out for capitalism might be supplied by an information economy. However you have a close to static physical economy and all your growth is coming from an information economy it isn't going to be too long before the information economy will become the dominant force. First of all that is only going to work if humans spend all their time consuming information (basically you live in a pod being drip fed and your brain is wired directly into the net). Secondly there is the problem that exists already that information, since it can be endlessly duplicated, does not lend itself well to capitalist scarcity economics. This would become a much worse problem if information was the dominant product. Repressive "intellectual property" enforcement is possible but as information comes to dominate the economy this may negate the advantages of capitalism and make feudalism more attractive.

In any case it is only a short term solution anyway. Information takes matter and energy to store and process it and so an exponential growth of information would in the end be unsustainable as well. All you get is a delay a few hundred years or so while your information grows until all your resources are used in constructing devices to hold it. After that you are back to exactly the same situation. Any growth in information needs a proportionate growth in physical resources and so it just becomes a problem of needing to turn all the matter in the universe into computers in a couple of thousand years.

I disagree with your arguement that "desire to survive as long as possible and reproduce" has anything to do with need for economic growth. The slightly negative population growth in many of the richest northern european countries clearly shows that given the choice people do not want unsustainable numbers of children. As for a desire to survive as long as possible this would seem to be best served by making sustainable use of resources as well. The actual cause of any desire amoung ordinary people for economic growth, is inequality. The only way, within capitalism, that ordinary people can get nearer the standard of living that they see the elite has, is if the economy grows and a little trickles down to them. Of course the elite makes sure they get a larger share of the growth, so the target the poor are chasing is accelerating away into the distance. Hence it is the system that is the problem not the people.

Regarding definitions and alternatives to capitalism you yourself seem to be defining captialism as "not a state planned economy". This is an extremely narrow viewpoint based on considering the two most widely used economic system of the past century and ignoring all other alternatives. In reality there are many different alternatives to capitalism from the ancient greek gift economy to anarchy (libertarian socialism). The one thing that we can be certain about the economy of a long lived spacefaring civilisation is that it will not be based on capitalism, since a capitalist economy must grow exponentially. As mentioned above, without a radical change in the heirarchical nature of society, it seems likely that when humans abandon capitalism in the near future, some sort of corporate feudalism will replace it.

[ Parent ]
Two explanations (4.00 / 1) (#106)
by Rainy on Fri Jan 24, 2003 at 12:02:22 AM EST

I'd like to argue with one of the common points that come up when people start talking about Fermi 'paradox'. This point goes like this: "Let's say there are civ's that are like ours and also are interested in contact. How would they contact us? They don't know we are here. Radio waves travel very slowly and dissipate quickly on large distances, and why would they use radio at all, maybe they're accustomed to different ways of communication?"

I think this is very wrong. The main reason is that it takes a very short time on universe timescale to settle whole galaxy and there are a 100 billion starts in it, so if even one of them evolved a similar civ only 10 million years ago, at least their probes would surely be here.

This means one of two things: chance of a civ emerging is much smaller than we thought or our ideas of further evolution of a civ are completely wrong.

The second possibility could mean that a young civ destroyes itself by some chance scientific experiment or by warfare, or by genetic error, or loses its will for power and expansion in warm and kind environment it builds for itself - sort of like a well-known theme of a hard working dad who creates a fortune for himself and passes it on to his son who happily spends it all on careless amusements and luxury. It could also be that a mature civilization ceases expansion and instead sits on its home planet and develops philosophy, does yoga, or tries to reach nirvana, not individually like some of us do now but as a whole civilization.

I don't see any particular reason to prefer one of these choices over the other one.
Rainy "Collect all zero" Day

There's another (none / 0) (#117)
by epepke on Sat Jan 25, 2003 at 01:23:50 AM EST

We're the first. At least, the first that hadn't yet relegated itself to one-world extinction, though that seems to be the plan. Somebody has to be the first. And if we weren't the first, we wouldn't be concocting Fermi paradoxes, because it would be obvious we weren't the first. Which, in a way, is an application of the weak anthropic principle that I hoped the original article would be about.

I agree that the argument about radio waves is silly. The last time I heard it was before cell phones were popular. Even if we got rid of broadcasting, there would still be enough signal from cell phone towers to be detectable, given enough time, with recievers we can build today, just about anywhere.

The truth may be out there, but lies are inside your head.--Terry Pratchett

[ Parent ]
True but.. (4.00 / 1) (#118)
by Rainy on Sat Jan 25, 2003 at 04:16:25 AM EST

The other two explanations are far likelier. There are 100 billion stars in our galaxy alone. Other galaxies aren't that far off (on universe time scales). We think that life could appear at perhaps one in 100 or 1000 stars - that's the estimate I've heard. Being first in face of such competition would be an amazing feat of luck! Winning a mere lottery a few times in a row got nothing on this..
Rainy "Collect all zero" Day
[ Parent ]
Likelihood (none / 0) (#119)
by epepke on Sat Jan 25, 2003 at 04:58:17 AM EST

They may seem likelier, but that's an emotional consideration. As with the anthropic principle, we only have one data point. We know that we exist, and we know that the large and obvious influence from other species we would expect to see we don't see. That's it. You can't do much in the way of good statistics with just one data point.

The truth may be out there, but lies are inside your head.--Terry Pratchett

[ Parent ]
Random clicks (1.00 / 2) (#115)
by dollyknot on Fri Jan 24, 2003 at 06:36:24 PM EST

I arrived here through a process of semi random clicks, live with it.

They call it an elephant's trunk, whereas it is in fact an elephant's nose - a nose by any other name would smell as sweetly.

They don't want to contact us... (4.00 / 1) (#135)
by ivancruz on Tue Feb 04, 2003 at 10:38:15 AM EST

because, we are made of meat.

Eu vou, eu vou vender a minha v, Eu vou vender a minha v, A minha v filosofia.(Zeca Baleiro)
The Fermi Paradox and the Weak Anthropic Principle | 138 comments (117 topical, 21 editorial, 0 hidden)
Display: Sort:


All trademarks and copyrights on this page are owned by their respective companies. The Rest 2000 - Present Kuro5hin.org Inc.
See our legalese page for copyright policies. Please also read our Privacy Policy.
Kuro5hin.org is powered by Free Software, including Apache, Perl, and Linux, The Scoop Engine that runs this site is freely available, under the terms of the GPL.
Need some help? Email help@kuro5hin.org.
My heart's the long stairs.

Powered by Scoop create account | help/FAQ | mission | links | search | IRC | YOU choose the stories!