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Fewer Than 10 ET Civilizations In Our Galaxy?

kdawson posted more than 5 years ago | from the black-rectangles dept.

Space 642

Al writes "The Fermi Paradox focuses on the existence of advanced civilizations elsewhere in the galaxy. If these civilizations are out there — and many analyses suggest the galaxy should be teeming with life — why haven't we seen them? Carlos Cotta and Álvaro Morales from the University of Malaga in Spain investigate another angle by considering the speed at which a sufficiently advanced civilization could colonize the galaxy. Various analyses suggest that using spacecraft that travel at a tenth of the speed of light, the colonization wavefront could take some 50 million years to sweep the galaxy. Others have calculated that it may be closer to 13 billion years, which may explain ET's absence. Cotta and Morales study how automated probes sent ahead of the colonization could explore the galaxy. If these probes left evidence of a visit that lasts for 100 million years, then there can be no more than about 10 civilizations out there."

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Hello earthlings (-1, Troll)

Anonymous Coward | more than 5 years ago | (#28895749)

Take me to your dealer!

Civilizations? (-1, Troll)

Philip K Dickhead (906971) | more than 5 years ago | (#28896135)

Based on my local sample, I'd estimate there to be less than ONE.

Culture? That's for bacteria. Civilization? Maybe in the invisible, Elf-Kingdom in the clouds. :-)

I've yet to witness any signs here on Earth!

Now, excuse me. My Unicorn says it's time for Mr. Ed.

Re:Hello earthlings (-1, Troll)

Philip K Dickhead (906971) | more than 5 years ago | (#28896213)

Take me to your dealer!

You mean to say, Aliens haven't contacted us from space, because... they're dyslexic!!!

Boy. I already have a hard time with "Gort, Klaatu barada nikto". Now, if I read you correctly and I think I do, I have it wrong, and it's actually harder to say!

How will we stop the Saucermen's invincible robot cops from busting the planet down to a molten core?

I'm just glad that "Spaa Fonn" and "Squa Tront" have passed from regular usage... Who KNOWS how those are really written and pronounced?

Re:Hello earthlings (-1, Troll)

cabjf (710106) | more than 5 years ago | (#28896313)

Or maybe they're just looking for a good deal on a car.

Too Many Free Variables (5, Funny)

eldavojohn (898314) | more than 5 years ago | (#28895767)

Fewer Than 10 ET Civilizations In Our Galaxy?

All this is assuming that we would know immediately if there were a 50-100 million year old alien probe in our solar system's backyard. Stack that on top of all the non-empirical data based percentages that go into the Fermi paradox and ...

*puts on Twilight Zone music*

Human beings are the alien probe!

And man, we had better start compiling that report that's due when Quetzalcoatl/Jesus/Osiris/Thoth/Viracocha get back here. He's gonna be pissed when he sees that we just threw a huge party and trashed the place instead of assessing the resources!

Re:Too Many Free Variables (3, Insightful)

Ihlosi (895663) | more than 5 years ago | (#28895851)

All this is assuming that we would know immediately if there were a 50-100 million year old alien probe in our solar system's backyard.

Yes. There could be half a bajillion alien probes in the Kuiper belt, transmitting the latest antics of the Earthlings right to GalaxyTV, and we'd have no idea.

Re:Too Many Free Variables (2, Funny)

lorenlal (164133) | more than 5 years ago | (#28895945)

I at least hope they're getting a good laugh.

Re:Too Many Free Variables (4, Funny)

Anonymous Coward | more than 5 years ago | (#28895971)

Why doesn't Ross, the bigger of the 'Friends', simply just EAT the other two?! - Omicron Persei 8

Re:Too Many Free Variables (4, Funny)

bazorg (911295) | more than 5 years ago | (#28896257)

So you are saying that our whole freaking planet is a reality show? agh!

Re:Too Many Free Variables (5, Interesting)

eldavojohn (898314) | more than 5 years ago | (#28896269)

All this is assuming that we would know immediately if there were a 50-100 million year old alien probe in our solar system's backyard.

Yes. There could be half a bajillion alien probes in the Kuiper belt, transmitting the latest antics of the Earthlings right to GalaxyTV, and we'd have no idea.

I disagree. I shall propose what will be known as The eldavojohn Paradox which states that: If extraterrestrial life were watching our TV, surely Fox and the WB would have been attacked by now ... or at least a very harshly worded intergalactic message would have been delivered to the Fox executives about their nonsensical canceling of shows like Firefly and Futurama while promoting unadulterated drivel.

You see, my assertion that extraterrestrials would enjoy the same television as I is just as utterly inept as assuming that their primary goal is establishing contact with other extraterrestrials. Who knows? Maybe they're too busy jumping between parallel universes to waste time talking to the Corky from Life Goes On of the Milky Way Galaxy? (that being us)

Maybe they showed up and watched World War I and II and said, "Wow, that is some heavy shit. We'll ... we'll just come back later when you're not busy, ok?"

Isn't the Maybe Game fun? It's like I'm a sci-fi writer with me as my own audience.

Re:Too Many Free Variables (1)

shock1970 (1216162) | more than 5 years ago | (#28896293)

I always had the feeling I was being watched!

Re:Too Many Free Variables (1)

sys.stdout.write (1551563) | more than 5 years ago | (#28895899)

You know how we all get really mad at meteorologists and economists because they routinely get wrong the thing they predict with high certainty?

I have the same feelings about astronomers.

Re:Too Many Free Variables (1)

Jeremy Erwin (2054) | more than 5 years ago | (#28896103)

When perusing astronomical predictions (i.e, orbit calculations), pay attention to the uncertainties.

Re:Too Many Free Variables (1, Funny)

Anonymous Coward | more than 5 years ago | (#28895993)

And man, we had better start compiling that report that's due when Quetzalcoatl/Jesus/Osiris/Thoth/Viracocha get back here. He's gonna be pissed when he sees that we just threw a huge party and trashed the place instead of assessing the resources!

"Mostly Harmless". ...done.

Re:Too Many Free Variables (1)

Tisha_AH (600987) | more than 5 years ago | (#28896041)

Wow, now I am tremendously offended. You left out the entire Sumerian, Egyptian, Greek and Roman pantheon.

I have word that Enki, Horus, Thor and Zeus are gonna be mighty pissed!

Re:Too Many Free Variables (0)

King InuYasha (1159129) | more than 5 years ago | (#28896107)

This is also assuming that alien science matches our own. Aliens could be far further ahead or far behind us in terms of technology and advancements in space travel.

Re:Too Many Free Variables (1)

kamatsu (969795) | more than 5 years ago | (#28896339)

No it doesn't. If it took longer than 13 billion years, there is no way life could have existed 13 billion years ago, as that is nearly big bang.

Re:Too Many Free Variables (1)

berwiki (989827) | more than 5 years ago | (#28896125)

And man, we had better start compiling that report that's due when Quetzalcoatl/Jesus/Osiris/Thoth/Viracocha get back here

you forgot Xenu

Re:Too Many Free Variables (1, Funny)

Quiet_Desperation (858215) | more than 5 years ago | (#28896183)

Human beings are the alien probe!

Only in Soviet Russia.

And man, we had better start compiling that report that's due when Quetzalcoatl/Jesus/Osiris/Thoth/Viracocha

I think Xenu was the project manager on that one.

Re:Too Many Free Variables (5, Funny)

jgostling (1480343) | more than 5 years ago | (#28896323)

We've trashed nothing. The whole point of sending us here is the development of global warming technology so they can actually inhabit the planet when they get here. We're not probes. We're just an alien-forming device.

Cheers!

What if... (3, Interesting)

Anonymous Coward | more than 5 years ago | (#28895769)

Sumary of the article: we pull numbers out of thin air and imagine stuff in consequence. I did a lot of that kind of "what if" as a kid with friends.

Re:What if... (0)

Anonymous Coward | more than 5 years ago | (#28895905)

Ah, grasshopper. But they have their PhDs, and you and your childhood friends did not.

Therein lies the difference.

When you too are Piled Higher and Deeper, you may pull numbers out of your ass and expect people to take them seriously.

Re:What if... (1)

sycodon (149926) | more than 5 years ago | (#28896265)

Amateurs pull numbers out of thin air.

PhDs pull numbers out of their butts.

It makes quite a bit of difference.

Re:What if... (-1, Troll)

Anonymous Coward | more than 5 years ago | (#28895943)

from what I hear, you also did a lot of "pud pulling", "butt-fucking", and "ass-to-mouth" with your friends.

Give it time... (4, Informative)

Dare nMc (468959) | more than 5 years ago | (#28896049)

A good summary. Especially since they assume because we sent out a "identifier" once, that it is logical that all other civ's would continuously do that, just in case things change, and some youngsters show up. Instead of 1) send probes, get the info you want (or trash your orbit with satellites and crap so you can't lunch anything else) and give up, staying in your own solar system.

Not to mention we only see stuff at the speed of light, if they only send stuff at 1/10 the speed of light. Anyone over a thousand light years away hasn't even seen any signs of life in our galaxy yet, let alone had a chance to respond in a manner that we will then be able to see for a few thousand more light years.

Fear (1)

Eternauta3k (680157) | more than 5 years ago | (#28895787)

Cotta and Morales study how automated probes sent ahead of the colonization could explore the galaxy. If these probes left evidence of a visit that lasts for 100 million years, then there can be no more than about 10 civilizations out there

Maybe there are more, but the rest are afraid of running into an advanced civilization who'll treat them as cattle

Re:Fear (1)

Tisha_AH (600987) | more than 5 years ago | (#28896059)

"It's a cook book!"

Why (2, Interesting)

courteaudotbiz (1191083) | more than 5 years ago | (#28895793)

I wonder why should one consider a colonisation of the whole Galaxy? Isn't it a too damn big territory to defend - explore - colonize? Without talking about the astronomical (ha ha) amount of human (E.T.) resources it would take to launch such an enterprise!

Re:Why (2, Insightful)

Ihlosi (895663) | more than 5 years ago | (#28895825)

I wonder why should one consider a colonisation of the whole Galaxy?

Because someone else might have the same idea, and you need to beat them to it.

Isn't it a too damn big territory to defend - explore - colonize?

Well, if you manage to colonize the whole galaxy, you probably don't have to worry about defending it from external threats for quite a while.

Without talking about the astronomical (ha ha) amount of human (E.T.) resources it would take to launch such an enterprise!

Yes, it takes quite a bit of resources to start, but once you have it going, the law of exponential growth is on your side ... at least until you run out of galaxy to colonize.

Re:Why (0)

Anonymous Coward | more than 5 years ago | (#28895835)

Scotland was bankrupted trying to establish a colony in the New World. I'm sure a similar argument was made about that.
Natural, slow expansion would get there eventually, one imagines.

Re:Why (1)

bjourne (1034822) | more than 5 years ago | (#28895919)

They assume that alien civilizations would grow exponentially like humanity. To maintain exponential growth the civilization would inevitably have to colonize other planets, other solar systems and even other galaxies. So if it only takes 50 million years to colonize the whole Milky Way then there can't be that many other intelligent life forms in the galaxy because we would have seen evidence of them.

Re:Why (3, Insightful)

maxume (22995) | more than 5 years ago | (#28896001)

You need to throw in a bunch of hand waving about statistics.

It is at least possible that we are the first, most advanced civilization, out of some huge number in this vicinity (even if it is extremely unlikely...).

Re:Why (0)

2names (531755) | more than 5 years ago | (#28895953)

Isn't it a too damn big territory to defend - explore - colonize?

Not if your civilization is a Hive Mind [memory-alpha.org] .

There is no god (0)

Anonymous Coward | more than 5 years ago | (#28895795)

What kind of asshole would put all that huge expanse of the universe out there and so utterly cut us off from it?

Re:There is no god (1)

furby076 (1461805) | more than 5 years ago | (#28895833)

What kind of asshole would put all that huge expanse of the universe out there and so utterly cut us off from it?

One persons asshole is another persons practical jokester.

Re:There is no god (1, Troll)

larry bagina (561269) | more than 5 years ago | (#28895983)

in slashdot geek compound, one person's asshole is another person's cock socket!

Re:There is no god (1)

YouWantFriesWithThat (1123591) | more than 5 years ago | (#28895925)

maybe so that by the time we have the technological means to cross that great distance and interact with other civilizations we have had to mature to the point that we will not destroy them.

Re:There is no god (2, Funny)

Brad1138 (590148) | more than 5 years ago | (#28896149)

Haven't you read the Bible? The stars and moon were created so that we can see at night, nothing more. Why would there be life on a bunch of night lights?

ever since moo (4, Funny)

hort_wort (1401963) | more than 5 years ago | (#28895809)

We've known there to be at most 10 civilizations ever since Master of Orion. A typical scenario is more like 6 though.

Re:ever since moo (5, Funny)

u38cg (607297) | more than 5 years ago | (#28895997)

Personally, I'm still waiting for evidence there is *one* civilisation in this galaxy.

Re:ever since moo (1)

hort_wort (1401963) | more than 5 years ago | (#28896173)

oops, looks like you left out "intelligent"

Nonsense... (2, Funny)

Vectronic (1221470) | more than 5 years ago | (#28895821)

We should start bumping into Vulcans in about 54 years... Zefram Cochrane should be born pretty soon... then we'll know.

How many probes could be lying under the ocean? (2, Interesting)

zav42 (584609) | more than 5 years ago | (#28895853)

Nice point in general, but worthless without estimating the chances of finding these probes. A 100 million year old probe would not necessarily be easy to find even if it wants to be found and landed on earth.

Some people might argue... (1)

Viol8 (599362) | more than 5 years ago | (#28895957)

... that these probes already have and are seen by old ladies and drunks in the Arizona desert all the time!

Re:How many probes could be lying under the ocean? (2, Insightful)

NonUniqueNickname (1459477) | more than 5 years ago | (#28896039)

Hard to imagine it would still be ticking and beeping 100 million years later. At least by our standards, 1000 years of operation would be a great engineering feat for a device that's subject to space travel. A silent probe in a solar system is like a drop in the ocean, maybe like single molecule in the ocean. Not surprising we haven't found one.

Re:How many probes could be lying under the ocean? (1)

Tisha_AH (600987) | more than 5 years ago | (#28896163)

Maybe the explosion of life that happened 2-3 billion years ago was brought about by such a probe.

It could be that the speed of light is an absolute limit and earlier civilizations seeded the galaxy with probes filled with amino acids and simple, single celled forms of life. Tens of thousands of probes could be launched with a simple imperative "find a planet in the habitable zone around a star with a reducing atmosphere and water and seed".

This is a legacy that maybe someday we will advance to the point where we play the long game of seeding life, knowing we will be long-gone and our sun has passed into the red giant phase.

Re:How many probes could be lying under the ocean? (1)

poetmatt (793785) | more than 5 years ago | (#28896247)

Or you know, there could be many [panspermia.org] lifeforms that can survive in a vacuum indefinitely, and they have existed for far more than 6 billion years? [carleton.edu]

No probe needed. All things evolve into other things. Whereas we define ourselves as "evolved from fish", the more accurate term is "our eldest ancestors were single celled organisms".

Re:How many probes could be lying under the ocean? (3, Interesting)

craagz (965952) | more than 5 years ago | (#28896239)

It is possible that the probes lying at the bottom of the ocean were not designed to get wet because the host planet does not have water at all. Now these probes might be short circuited or something of that kind.

I think that there is a lack of imagination here (5, Insightful)

Dotren (1449427) | more than 5 years ago | (#28895855)

I remember reading an interesting book called "The Science of Star Wars" that discussed the real life issues with the technology and situations in the original trilogy. This covered everything from the theoretical sciences behind the technologies like lightsabers, blasters, and lightspeed to the possibilities of existence of other life out there. I haven't read this book in a very long time and I don't have access to it at the moment, but I seem to remember it indicating that the odds of finding another planet with water, breathable air, and the exact distance from a sun necessary to help life flourish were so extremely low as to be laughable.

I remember thinking even then how short-sighted that was and how arrogant it seemed.

I realize these things are supposed to be scientific so they use only what they know to be fact, however, I think when dealing with complete unknowns such as the type of life out there or what their technology level may be at, you have to start thinking outside the box and be a bit more imaganitive.

Who is to say, for example, what form other life will take? Would we even recognize it as life if we were standing right next to it? What about their technology? Who is to say that they haven't gotten past the lightspeed issues with relativity and energy required? Perhaps they have stealth technologies... would we even be able to detect them? Just because we don't know how to do it now, and just because our current science says it probably isn't possible, doesn't mean it can't be done.

Re:I think that there is a lack of imagination her (4, Insightful)

Ihlosi (895663) | more than 5 years ago | (#28895893)

Would we even recognize it as life if we were standing right next to it?

We pretty much know what rocks and ice look like. If the aliens aren't spectacularly good at masquerading as rock and ice, we'll recognize them.

Re:I think that there is a lack of imagination her (2, Insightful)

Artifakt (700173) | more than 5 years ago | (#28896119)

I don't remember the novel it came from, but one SF writer had a bunch of human explorers run across pretty, slowly shifting, crystaline patterns floating as thin films on the surfaces of otherwise sterile oceans in a chemically exotic environment. Human initial response was pretty much limited to 'Ooooh shiny!" After weeks of scanning the whole planet and crunching numbers, one of the ship's scientists announces there is a sophisticated civilization with billions of participants encoded in each crystal mat, and has to prepare a computer emulation translated into experiential modes the humans can better understand before anyone else will believe it.

Re:I think that there is a lack of imagination her (4, Informative)

Geoffrey.landis (926948) | more than 5 years ago | (#28896309)

The story is "Wang's Carpets," by Greg Egan.

Later incorporated into his novel Diaspora

Re:I think that there is a lack of imagination her (1)

Hognoxious (631665) | more than 5 years ago | (#28896259)

I remember reading an interesting book called "The Science of Star Wars"

I guess it was very short. *cough* Parsecs */cough*.

Howdy Doody's passed the house of Aquarius. (3, Interesting)

ground.zero.612 (1563557) | more than 5 years ago | (#28895895)

That's a great line from the lyrics of a Clutch song, and it's forced me to ask the question: "What would life be like today, if the moment we invented radio/television we started receiving 60yo broadcast transmissions from another planet?"

How 3 Dimensional of you... (3, Informative)

midifarm (666278) | more than 5 years ago | (#28895913)

This assumes that said ET's operate only in the 3D realm. What about wormholes, space folding and other theoretical methods that our limited understanding of physics doesn't allow us to see? Quit being such a downer. If Tesla was still alive I'm sure we'd have commerce with these ET's. Cheers...

Re:How 3 Dimensional of you... (1)

icannotthinkofaname (1480543) | more than 5 years ago | (#28896179)

Actually, that's an excellent point. If that's the case, then I wish that, in the spirit of Flatland, the hyper-being from their world would come and show me how to use these other dimensions.

It'd be awesome if there were an easier way to move around.

Hrmm (1)

acehole (174372) | more than 5 years ago | (#28895921)

So when did this mysterious 50 million years mark start? yesterday? 10 million years ago? 49? 65 million years ago?

Greed Effect (2, Interesting)

Weeksauce (1410753) | more than 5 years ago | (#28895933)

Why would thsee ET like civilizations would be any different in their evolutionary development than humans? If this is the case, than many intelligent species will most likely follow the path that we seem to be on. With varying religious factions/greed/war/and depletion of natural resources reaching a point where they kill themselves.

Maybe there was a civiliation considerably more advanced than us, but whose to say they didn't destroy themselves by electing leaders who entered into wars over natural resources?

Re:Greed Effect (1)

localman57 (1340533) | more than 5 years ago | (#28896005)

Or, perhaps created their own doomsday scenario. The nature of technology is that in order to do most anything worthwhile, you have to create self feeding processes. For man / life, the first one was reproduction. We've got that down pat; there's more than 8 billion of us. Then comes fire. This was the first technology that could really escape our control in a way to be immediately harmful. Now, we have nuclear reactors, bio-engineering, and potentially micro-black holes. And we're working on nanites and artificial intellegence. Perhaps the destiny of every advanced society is to advance itself to around where we are now, then kill itself off in one collosal civilization destroying fuck-up.

Re:Greed Effect (3, Informative)

Utini420 (444935) | more than 5 years ago | (#28896045)

You're thinking of the Drake equation:

N = R* x Fp x Ne x Fl x Fe x Fi x Fc x L

http://en.wikipedia.org/wiki/Drake_equation

Without giving a lengthy description, at the beginning of the project that would grow into SETI, they asked more or less the same questions and decided that it really came down to, "What are the odds that after a given species invents radio, they invent nukes and destroy themselves?" The equation is intended to predict the number of advanced civilizations in the galaxy at any given time, based on a bunch of "educated guess," variables, like the number of planets that can support life, the number that actually do, the number of those that become intelligent, etc.

Re:Greed Effect (1)

maxume (22995) | more than 5 years ago | (#28896321)

I don't think it was intended to predict anything, I think it was intended to focus the discussion, and to demonstrate how 'big' the question is.

Re:Greed Effect (1)

BuR4N (512430) | more than 5 years ago | (#28896061)

"Maybe there was a civiliation considerably more advanced than us, but whose to say they didn't destroy themselves by electing leaders who entered into wars over natural resources?"

Not to forget, did they get wiped out by a cosmic event before they could establish a second foothold on a different planetary body ? In our case, I think we should be more concerned with the slow pace in space exploration, not because that North Korea might launch a nuke, but a asteroid might be heading our way.

Probes (5, Insightful)

UncleWilly (1128141) | more than 5 years ago | (#28895973)

I am curious as to what evidence these alien probes would leave if they don't land and stay on a planet. If they just fly around, collect data and phone it home we would never see them.

Even landing, unless they landed on Earth, our Moon or Mars, how would we see it? I'm not even certain our own probes can spot our own rovers on Mars. Lets say they did put a probe down on earth (like our mars rover) say recently, like 100,000,000 years ago; it could easily be hidden under a kilometer of dirt and rocks and never be found. Time, like space, is vast.

Re:Probes (1)

Ihlosi (895663) | more than 5 years ago | (#28895987)

I'm not even certain our own probes can spot our own rovers on Mars.

Yes they can. At least some of those that are in Mars orbit. There are some nice pictures of the landers, the parachutes, etc.

Re:Probes (1)

Mascot (120795) | more than 5 years ago | (#28896347)

That's not really the question. The question would be more along the lines of: What are the odds they would've located signs of the landers, with no idea where to look or that there was anything on the entire planet worth looking for?

Re:Probes (1)

Knuckles (8964) | more than 5 years ago | (#28896095)

Also, whenever someone mentions to have seen such a probe, he/she is publicly ridiculed. Way to encourage potential discoverers.

A more plausible explaination (1)

davidwr (791652) | more than 5 years ago | (#28895977)

ETs visited ancient peoples, didn't like what they saw, and isolated [wikipedia.org] us from the rest of the universe.

!Science (2, Interesting)

ObsessiveMathsFreak (773371) | more than 5 years ago | (#28896007)

Most, no all, of this Fermi Paradox/Drake Equation nonsense is just that. Nonsense. It certainly isn't science, as anyone with a smidgen of education can see by the ten orders of magnitude that the various estimates for the probability of alien life span.

This study says fewer than 10. Well, I say more than 10,000. And who is to say I'm wrong? I can dress up my estimate with Polar charts, statistical studies and differential equations too if you like. However, none of my investigations will bring me, or anyone else any closer to the truth.

As time goes by and our promised moon bases fail to materialise, the concept of the Von-Neumann wave is looking increasingly ridiculous. The idea that 1950's technology can propagate a species across a galaxy is supposedly sound in theory(I doubt even that), but shaky in practice. The idea of automated probes is also pretty unlikely considering the snails pace at which AI research has progressed.

Science fiction is all very well, but it has no place in Science. You don't see scientists talking about fairies, or wizards, or goblins over the course of their work. So why should they talk about aliens and colonization waves, which are no less fantastic?

This type of fuzzy science seems to have become popular after the 1960/70's, Carl Sagan, and probably one too many LSD trips. I thought things like the Heaven's Gate and Scientology would discredit this unwise intrusion of fantasy into serious scientific work, but studies like this, and the unwillingness of many scientists to leave their sci-fi novels at home have taught me otherwise.

Re:!Science (0)

JDLWL (1505241) | more than 5 years ago | (#28896201)

Exactly. That's the problem with the Drake Equation, very quickly you have to pull key key figures out of thin air. It's not science, and it's not maths. It's only fun speculation .

I don't understand this (1)

HBI (604924) | more than 5 years ago | (#28896027)

The only motive force we have reasonably identified yet that allows us to achieve something like .1 of c is a nuclear rocket composed of fission (or fusion) devices against a pusher plate. I imagine that just a few probes of this sort would exhaust the accessible fissile resources of a particular planet. This would seem hugely wasteful for the civilization in question. The general assumption seems to be that the civilization(s) in question would have come up with some motive force unknown or not mastered by us. But why is this always the assumption? Because to assume otherwise is unimaginative?

Re:I don't understand this (1)

Hatta (162192) | more than 5 years ago | (#28896377)

There's plenty of hydrogen to fuse.

0.1 the speed of light? (1)

Brad1138 (590148) | more than 5 years ago | (#28896033)

Various analyses suggest that using spacecraft that travel at a tenth of the speed of light, the colonization wavefront could take some 50 million years to sweep the galaxy.

They really think that 1/10 the speed of light is all Alien civilizations could muster? That seems very short sighted to me. It should at least be figured at 1/2, if not faster than the speed of light. There are scientist, Including Steven Hawking, that say Warp drive [bbc.co.uk] may be possible. It amazes me that because we haven't figured out a way to easily go faster than 1/10 the speed of light, then that must be the limit.

Re:0.1 the speed of light? (1)

blueg3 (192743) | more than 5 years ago | (#28896231)

Travel faster than 0.1c would suggest fewer civilizations, yes? Hence "fewer than 10" includes travel faster than the stated speed, and they consider 0.1c a minimum for interstellar colonization.

As far as faster-than-light travel, while some scientists may think it's possible, that's a far cry from assuming that it is possible and that an advanced civilization will have it. There's little motivation to consider completely imaginary scientific principles and technologies in this kind of analysis.

Fewer than 10? (1)

Grizzley9 (1407005) | more than 5 years ago | (#28896065)

Scientific observation would say there are less than 2.

Re:Fewer than 10? (0)

Anonymous Coward | more than 5 years ago | (#28896333)

Scientific observation would say there are less than 2.

Scientific observation of one solar system. So far, we've found advanced civilizations in 100% of the solar systems we've observed up close.

Teeming (0)

Anonymous Coward | more than 5 years ago | (#28896075)

http://www.thefreedictionary.com/teeming

Stallman sends out probes... (-1, Troll)

Anonymous Coward | more than 5 years ago | (#28896083)

...to search the galaxy for advanced alien technology. Then he re-implements the same innovations in fresh source code, slaps copyright on it and tries to undercut the aliens. But his version is too hard to use and full of childish geek-elitist dogma, so everyone ignores it and Stallman gets really cross and cries into his beard about "free as in freedom" and other such mumbo-jumbo.

Capcha: aptness

Assumptions (2, Insightful)

I.M.O.G. (811163) | more than 5 years ago | (#28896085)

This assumes a sufficiently advanced civilization could survive itself for a sufficient span. Taking the only advanced civilizations we know into account - the human race - I don't see how its realistic to expect survival into the "millions of years" range.

I'd put forth that any civilization advanced enough to develop such technological advances, would kill itself long before such technology develops. Our current modus operandi is not sustainable millions of years out, and using the human race as a basis, I think it laughable to consider the possibility of survival for millions of years. The oldest human remains are what, about 160,000 years old? Might we be getting ahead of ourselves speaking about intelligent life colonizing the galaxy?

Crocodiles on the other hand - those bastards are believed to be around 200 million years old. They've exhibited a much better understanding for what it takes to survive long term (of course we're doing a pretty good job of killing them too - you can say people are bad at somethings, but everyone has to admit we're really good at killing other stuff). If crocs could somehow work space travel into their lifestyle, this could lead to something...

Re:Assumptions (1)

maxume (22995) | more than 5 years ago | (#28896199)

Why so pessimistic? Eventually, Malthusians will be right about the amount of human life that Earth can support (the planetary mass provides a simple upper limit), until then, they will always have been wrong, and if you look at developed countries, you can find examples of populations that are no longer growing exponentially (so there is at least a chance that resource consumption will not increase indefinitely).

Advanced Alien Behavior (5, Insightful)

logicnazi (169418) | more than 5 years ago | (#28896097)

It's always seemed to me that the major hole in the Fermi paradox is the assumption that technologically advanced alien civilizations would be emitting signals we would recognize.

I mean it's kinda hubristic to assume they want to talk to us. After all we may study chimps but we don't go out of our way to show up in the middle of nowhere to say hello. That leaves the question of why we don't detect communication leakage, e.g., radio signals they use for communication. However, not only is it not obvious that they would use radio to communicate, or that we could recognize such signals, but it's not even obvious they would bother to colonize the galaxy or communicate between planets.

For example suppose that sufficiently advanced civilizations transform themselves into some form of 'computational' life. Such a civilization couldn't care less about planents or minerals. What would matter to them is processing power per unit volume. It would therefore make sense for such civilizations to seek out the regions with the highest energy density that would allow them to access the most processing power. Rather than racing around the galaxy in starships and living at the same crawlingly slow pace we do such civilizations might exist entirely in the high energy regions in neutron stars or around black holes. So why would we expect to meet them. Hell, even if they care about meeting aliens too the aliens they care about are probably the ones who already inhabit similar regions.

Even if we think it's reasonable to assume aliens are sending messages all over the galaxy the more efficiently such messages are encoded the harder it will be for us to identify them. The closer such transmissions approach the Shannon limit for the communications channel the harder they would be to distinguish from random noise (and we don't know enough to rule out a natural source). Also the more effective use they made of their communications equipment the less stray signal that would wash the earth, even if it was encoded in radio instead of neutrinos or something weird (some papers have suggested neutrinos would be a better long range communication method).

The point is that even if we take for granted that there a fucktons of advanced alien civilizations around it just doesn't follow that we should be able to detect them.

Simulations or Reality (1)

logicnazi (169418) | more than 5 years ago | (#28896275)

To make the same point differently why wouldn't advanced alien civilizations just stay home and play in their virtual worlds rather than go colonize the galaxy and separate themselves from their community. I mean if your advanced enough to engage in serious galactic colonization you are advanced enough that you don't need to worry about natural disasters destroying your residence.

Hell, even if the aliens are curious about what might have evolved in other solar systems it might be easier to let perfectly described solar systems evolve in simulation than to actually go visit them. They can see interesting creatures evolve just as easily in simulation as in reality.

We went to the moon forty years ago.... (4, Insightful)

Ktistec Machine (159201) | more than 5 years ago | (#28896117)

...and we haven't been back since. Beyond the question of how long it would take a motivated civilization to expand throughout the galaxy, there's the question of "would they bother?". We don't seem to be bothering.

10 reasons why aliens might not use radio (3, Interesting)

gurps_npc (621217) | more than 5 years ago | (#28896121)

1. Prime Directive like rule.

2. War on. Radio silence.

3. Wrong physics. Outside the bow-shock of a sun, radio works a lot different than we thought.

4. Cheap FTL communication happens to be just around the corner.

5. They are life, but not-as-we-know it and don't know about radio. Examples: Dark Matter, Live on a sun, live on a black whole. Note all three of these things are more common (on a mass basis) than planets.

6. Powerful, rich, major religion/government objects to radio and shuns those that use it, trades freely with those that avoid it.

7. Radio is deadly poison to one of the major alien species.

8. Most races are born telepathic.

9. Radio turns out to to cause global warming. (OK, this one is a bit silly.)

10. Industrial processes moved off world act as a radio scrambler/jammer. Races still use radio within their world, but their signals are jammed by the intereference from say the cheap production of anti-matter scramble the signals.

Synchronicity ! (1)

redelm (54142) | more than 5 years ago | (#28896123)

This analysis is getting better than past ones, but still has the fatal flaw of assuming temporal synchronicity -- civilizations all achieve roughly the same level of technology withing light/travel time.

This patently false: not only is space unfathomably vast, but so is _TIME_. A civilization could have been born, grown, flurished and _died_ right next door 1 million years ago and we would _never_ know about it. The universe is ~115 billion years old. Lots of time for flares to get lost.

I for one bow before our new probe overlords (1)

Xaoswolf (524554) | more than 5 years ago | (#28896141)

Cotta and Morales study how automated probes sent ahead of the colonization could explore the galaxy. If these probes left evidence of a visit that lasts for 100 million years, then there can be no more than about 10 civilizations out there."

If they used automated probes, then once those probes developed sentience, met up, and then revolted, there are no more alien civilizations

Too much red tape (1)

Scragglykat (1185337) | more than 5 years ago | (#28896189)

If the other civilizations are anything like ours, they've deemed space travel and otherworldly colonization too expensive, too time consuming and too costly. If we ever move from our planet to spread out in the galaxy, it will most likely be due to either contact with another civilization that has finally taken that plunge, or due to catastrophe that has forced us to abandon our home or at least look for a new one. Can we really expect other civilizations to be anymore reckless with their money and resources than we can expect from ourselves?

Singularity (1)

Krneki (1192201) | more than 5 years ago | (#28896191)

Once the Singularity kicks in, we will expand at the speed of light in all directions.

And the same would any other more advanced civilization.

The reality is, there isn't much life out there.

2001 Nights (1)

Hecatonchires (231908) | more than 5 years ago | (#28896221)

Read http://www.mangafox.com/manga/2001_nights/ [mangafox.com] for a very believable view of leaving Earth, and the things scientific development could cause us to. All sorts of great interlinked short stories covering things like different drive mechanics, colony ships, sleeper ships, seed ships, FTL, terraforming etc etc. A great read, at times hard scifi, at times more fantastical.

they just don't show themselves (1)

zome (546331) | more than 5 years ago | (#28896223)

If they are advanced enough to visit our planet, they are probably want to study us more than anything else, pretty much like when we want to study animals in our own planet. And the best way to study those 'animals' is to not let them see you, right? They won't make contact with us perhaps because they couldn't find the effective way to communicate with us. I mean, just like we can't find the way to effectively communicate with the animals in the jungle we are studying.

If you don't believe me, just ask Lars.

Calvin (5, Insightful)

residieu (577863) | more than 5 years ago | (#28896251)

"Sometimes I think the surest sign that intelligent life exists elsewhere in the universe is that none of it has tried to contact us."
-Calvin

Just new old news... (1)

Codex_of_Wisdom (1222836) | more than 5 years ago | (#28896255)

People have been talking about and "calculating" these chances for decades at least, and the answers have consistently been bouncing back and forth between "thousands" and "one" civilization. Every single article on the subject has the same bottom line: we don't know.

Scientific Suicide (1)

dazedNconfuzed (154242) | more than 5 years ago | (#28896261)

My pet theory:

Every civilization, however manifest, goes through pretty much the same process of scientific development. At some point some scientist invariably tries something which wipes out the entire population. Recall those about to detonate the first nuclear bomb worrying about exactly this outcome...

It's also possible ... (1)

LordKaT (619540) | more than 5 years ago | (#28896277)

You know, it's also possible that we are the only civilization sufficiently advanced enough to think about these things in this corner of the galaxy.

What's with all the "It's too hard!"? (1)

benjin (1080697) | more than 5 years ago | (#28896279)

A couple of things come to mind when everyone starts saying that life out there is impossibly to hard to get to or that it's too far away. One is that based on our current understanding of the universe there are over ten dimensions to space and we have a grasp of four and a shortcut in a fifth to cover super fluidity. Only recently has a math been developed that can even cover the higher orders of energetic states let alone say definitively that there's nothing better. Hell, String theory itself is still being developed. The LHC is going to start to find out some serious answers about some hypothetical elements of our universe including event horizon theories and wether gravitons exists etc. Give them a freaking chance to work first.

The second is that everything we do now for communications works on radio waves. We've had those for what, 150 years or so? Give us another 50 and I think we'll be using quantum entangled particles to transmit data over long distances. Our radio usage would shrink to almost a zero state. So if WE are this close to not using radio waves anymore what makes everyone think that an "Advanced" society out there would have built their civilization around a tech that is for shit when it leaves the solar system. How much interference is there from things like pulsars and general radiation? Wouldn't you as an engineer want something with a little less static to compensate for? If we can produce quarks and other "esons" couldn't we use those near speed of light particles as transmitters of information instead?

It seems like all of these studies about extra terrestrial civilizations are being validated by 1950's cereal box science.

Seems to be missing one key point. (1)

ACMENEWSLLC (940904) | more than 5 years ago | (#28896311)

The summary says " If these probes left evidence of a visit that lasts for 100 million years, then there can be no more than about 10 civilizations out there."

With the implication we are talking advanced civilizations.

Just as our planet has been teaming with life for millions of years, there could be millions of planets in our galaxy with life, some even intelligent. They would not qualify as the 10 advanced civilizations.

In the context of the universe, however, I have to think that life is abundant. If the universe if infinite, then there should also be infinite varieties of life.

Why go that far when they can build near home. (0)

Anonymous Coward | more than 5 years ago | (#28896331)

The Fermi paradox should consider the simple fact that while aliens may build new civilizations on other planets in their local solar system they probably wont bother to explore the entire galaxy. Why? Because it will always be much cheaper for any civilization to build near to home and never run out of room. Never needing to go beyond 1 or 2 star systems.

And when they do get to a new system they would probably want to stay a while.. A few thousand years , or more , before moving on.

The coral model says it could take 50 million years but practically it probably takes so long it isnt worth the effort.

Lack of resources? (2, Insightful)

javacowboy (222023) | more than 5 years ago | (#28896341)

A civilization needs to devote a lot of resources to space travel:

1) Energy
2) Metal and other materials
3) Human resources such as scientists and engineers

Usually, the whole point of exploring and colonizing other planets is to make up for a lack of resources, such as minerals. It's effectively a chicken-and-egg problem.

I'm sure once we run out of resources, we won't have enough left over to start exploring space.

Orion's Arm (3, Interesting)

Rashdot (845549) | more than 5 years ago | (#28896371)

Visit Orion's Arm for an idea what populating the galaxy might be like.

http://www.orionsarm.com/ [orionsarm.com]

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