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Winning the E.T. Lottery
Consul writes "Space.com has a cute story about the statistical probabilities that we have been visited by an alien civilzation. He seems to make a convincing argument."
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The probabilities for either event are infinitesimal, at least in my opinion, yet here we are. Even if you discount the above two occurences and bring up intelligent design or pure creation you're faced with yet one more improbability:
If you look at any of the probabilities they seem to point to a vanishingly small probability that even the simplest forms of life exist, let alone any intelligent life. Yet we're here.
Chris Kuivenhoven is a thief, beware
...is that, either:
1) Faster-than-light (FTL, warp, whatever) travel is possible, and nobody's invaded us because there's some overarching federation of planets that's keeping us protected from outside influence until we're ready, and that's way cool.
or
2) FTL travel is not possible, and so nobody's coming here 'cause it's just not worth the trip. And that's depressing as hell.
Am I missing anything?
The problem with this is that analysis like this are simply interesting reading and speculation. Nothing more. Barely science and really not past the hypothesis stage (there is no evidence he is correct).
I can find good arguments for both why or why not other worlds may have life or intelligent life.
-Sean
All it takes is for someone, somewhere to build an intelligent(ish) self-replicating machine programmed to spread throughout the galaxy - one per interesting star system.
Such a system could cover the entire galaxy in a couple of million years easily (and cheaply after initial design/construction cost). They can do whatever you like; sit and watch, make contact, try to destroy any competitors (The Forge of God style; soon to become a set of movies, yay), and call home (since you end up with a network of them; sure, it'll take a while to get back home, but it's one hell of a cheap way to learn an awful lot about the galaxy).
Given that it only takes one civilization to have done this, and given that our solar system is probably quite interesting given it's layout, I wouldn't put too high odds on there NOT being such a device hanging around near here.
If aliens exist and perfected something similar to cryo-freeze, and had extremely long lifespans to boot, I'm sure nearly all of them that fit into that category would eventually hit Earth on their tour of the Universe.
Pioneer
Or perhaps the aliens sent life-creating probes to thousands or even millions of star systems.
Imagine if we found that life is unique to Earth, but there are tons of planets out there capable of supporting life. Now we build a probe that will go to one such system. This probe determines what planet in the system has the best chance of supporting life, and it goes into orbit around it. Over time, it launches capsules with increasingly more complex life forms. This is done in conjunction with monitoring of the planet's atmosphere to encourage Earth-like development. We mass-produce said probes, and launch one to each of our neighboring star systems, expanding our definition of "neighboring" as we continue to produce the probes.
Now when we get around to colonizing the stars, we have planets ready for us.
It should be pointed out that if extraterrestrials are visiting earth, it is highly probable that they have some means of travel that exceeds the speed of light (wormholes or something?). I won't speculate on how this is done, since I'm not a physicist.
However, if they do have the resources to do this, then it would be reasonable for them to be able to set up monitoring stations all over the galaxy (in the space of a few million years) to listen for the radio signature of a new intelligent civilization popping into existance (ours, sadly, was Adolf Hitler). Said monitoring station would use whatever technology allows them to exceed the speed of light, and send a message back to their home base letting them know that somebody just invented television.
After that, the aliens hop into their little flying saucers, head for earth, abduct people, and probe their nether regions.
At any rate, the article is bunk, because the assumptions it takes are a bit too selective, and it fails to explore some very obvious possibilities.
According to the most popular view of this matter, extraterrestrial craft have been flitting across our skies since 1947.
...not for billions of years)... maybe thousands, but not millions. The ratio part: A few dozen to us may be .000000002% of our population, but a couple thousand of them might be the same percentage... Who cares about boreno? Earth probably holds a great intrest to them... more than borneo to us.
I thought the most popular view was that they have been visiting for thousands of years... depicted in writing and art all throughout history...
That's 55 years in a planetary history of 4,600,000,000 years.
What about their planet's history? It's possible that they havent been able to travel to other planets for that entire time... more like a couple thousand years? Then the ratio is more realistic. (I just love misleading journalists...)
it implies that there have been millions of expeditions to Earth! We may send the occasional anthropological research team to Borneo, but we don't send millions.
Think ratio and intrest... first, it doesn't emply millions (how long have they been able to get here?
And it's a lot easier to get to Borneo than to traverse hundreds or thousands of light-years.
Before our technology developed, we couldn't even get across the damn ocean... so boreno would be a pretty hard place to get to for us thousands of years ago (...from the US). It's probably pretty easy for them to traverse "hundreds of thousands of light-years".... if they even have to go that far. I doubt they come from the other side of the galaxy...
Let's set aside the question of whether advanced galactic societies would have the slightest interest in our wars, our pollution problems, or our reproductive systems.
Why do you think humans research organisims on our own planet? We even hold a great interest in organisims at the bottom of the sea where we thought that life couldn't exist... We're different from them, and they have a hunger for knowledge...
The real question is, how would they know about us at all?
...telescopes? Passing by one day? Sub-atomic microtransponder galactic scanners that they have and we havent even imagined up yet? There are plenty of ways to find us...
I'd comment on the microwave signals we've sent out and your opinion on that... but there are other ways of them knowing we're here... (that takes care of about 3 paragraphs)
One sided journalism gets to me... so now I had to go and balance it out...
Sometimes I feel as though one should need a license to practise maths.
It makes little sense to calculate the probability of something that has already occurred. If we have been visited (and as a self-described space nut, I'll admit I find the possibility positively knee-weakening), then that stands as evidence on its own that our being visited is possible.
I have heard similar arguments for why the end of the human race is very near. The reasoning goes, that since the human population is always growing, it is more probable that I would be born in the 20th century than in any century prior. But wouldn't it then be even more probable if I were born in the 25th century? In fact, the chances of my being born in the 20th century would be vanishingly small. Therefore, it is safe to assume that there will be no people in the 25th century.
You can prove nearly any crazy idea with this kind of "thinking."
"I'm a rocket man / Rocket man burning out his fuse up here alone." - Sir Elton John
They spice up our water/air/primordial-soup with some pre-life cake mix and then fly away. They tell all their friends to come and visit when they get the chance, you know, just to look in and see how things are going. Well, then we get visited by aliens for the next few billions years (assume they have long life spans, or collective memories).
Seems this scenario gets rid of all of his improbable probabilities.
...And instead gives the improbable scenario of aliens stopping by tens or hundreds of millions of times over the Earth's history. This would take a significant expenditure of resources, to little end (especially since the hypothetical ant-farm alien could have seeded a barren world in their own system or otherwise closer to home for convenient visiting). It would also require lots and lots of patience and dedication that would probably be more entertainingly spent elsewhere.
In summary, I'm doubtful of this scenario.
It appears, depressingly, that modern physics is telling us that FTL travel is not possible, and never will be.
Actually, our existing understanding of physics suggests several interesting possible approaches to FTL travel. These are already being studied to some extent; time will show whether they're practical or not.
We also have enough gaps in our understanding to leave room for potential methods of FTL travel. We just know that it isn't terribly easy, if it is possible.
I think that is the most likely explanation. No civilizations make routine interstellar trips simply because it is so expensive.
That's one possibility.
Another is that life is uncommon enough that even frequent-FTL-travelling civilizations wouldn't be near enough to us to have found us.
Another is that the active lifetime of civilizations tends to be short enough that nobody happened to be alive (or at least interested in contacting people) during our history to contact us.
Or a combination of the above.
It will be interesting when we finally have enough information to be reasonably sure which is the case.
Lars T.
To the guy who modded me down from perfect to terrible Karma - Apple haters still suck
I go for your #1, because of what I call the Bombs-to-starships gap.
Even today with the paltry stuff we practice, space travel is horribly energy-intensive. While it's believable that we'll get more efficient, we still don't have much interplanetary travel, much less interstellar. We will have to acquire the ability to control more energy.
My premise: If a species has more than the slightest tendancy to use weapons against itself, it will not survive to build starships. That includes us. We have the next few centuries to burn some of our most terrible aggressiveness out of ourselves, or else we'll use that same energy to blow ourselves up. Actually, the Cold War was a great success story, since we *did* develop a survival mechanism that held us through half a century. We've more work to do, because greater energies are on their way, with more chance for abuse. Moreover we've got to improve the common man, as rather common men turned relatively safe transportation devices into bombs last year.
One hole in the theory - alien psychology such as a highly xenophobic hive-mind.
The living have better things to do than to continue hating the dead.
Aliens visit us all the time. Those nasty grays are always letting their El Chupacabras run loose.u ncoveror.com/chupa2.htm/ chupa3.htm
n coveror.com/martians.htmm /mars2.htmh tm
. uncoveror.com/microunix.htm
One in California bred with a dog, and a Chupa pup is wreaking havoc in Massachusetts.
http://www.uncoveror.com/chupa.htm
http://www.
http://www.uncoveror.com
http://www.uncoveror.com/chupa4.htm
They have attacked us with Solaranite.
http://www.uncoveror.com/invaders.htm
The Air Force and NASA know it, and are covering it up!
http://www.uncoveror.com/ufos.htm
http://www.u
http://www.uncoveror.co
http://www.uncoveror.com/zhtitikofft.
And we got UNIX from the computers on the Roswell UFO! Microsoft has even used this alien technology.
http://www.uncoveror.com/aliens.htm
http://www
We report this stuff on The Uncoveror all the time, but people still don't seem to know about it!
(music)It's my website, ans I'll deep-link if I want to!(/music)
The Uncoveror: It's the real news.
Like I said, I can't accept that planets like Earth are as common as dust. Perhaps life is, but I think there's good reason to think that advanced multi-celluar life, with millions or billions of species, is a bit more rare. Consult one of many tables of "Things we need to live"; large moon, proximity in the past but not present to supernovas, a certain element mix, relatively placid position in the galaxy (a recent article suggested as little as 10% of our galaxy may be habitable in the long term, as too many stars routinely pass through excessively active areas), high elements, perhaps a routine asteroid cleansing, the list goes on. It's by no means a done deal that Earth is uninteresting.
And even if it is perfectly common... so what? An advanced civilization would still leave a probe, just to see if anything interesting happens. It's not like a probe is very expensive on their terms.
Think like a scientist... Earth doesn't have to be interesting, just potentially be interesting at some point in the future. That's why I say it could have happened millions of years ago.
...And instead gives the improbable scenario of aliens stopping by tens or hundreds of millions of times over the Earth's history. This would take a significant expenditure of resources, to little end
Why not just drop a probe in orbit after they dump the cake mix? E.T. phone home...
It's a heck of a lot easier, plus NORAD probably can't even detect them today. Heck, we can barely find grazing asteroids. Stick one at a LaGrange point, and I doubt we'd ever see it.
My God, it's Full of Source!
OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
The age of the earth doesn't matter for this kind of calculation. What matters is the propensity for space travel of aliens, the duration of trips, the prevalence of earth-like planets, the expected lifetime of spacefaring civilizations, and the ability of aliens to detect earth-like planets.
A probability this complex can only be observed, not computed. Observed probabilities are meaningless with a sample size of one.
It is true, of course, that if we see, say, 1 visit per year (the same spacecraft flying around the planet a few times, resulting in many sightings), there must have been 1 million visits over the last million years, but so what? A million years is a long time.
Of course, more likely, aliens pick planets to visit based on whether they might harbor interesting life forms, which means that the frequency of visits probably has increased greatly over the last hundreds of millions of years.
It seems pretty unlikely that aliens frequent our modest little sphere. I just can't see what they would get from a field trip, that they can't get from our broadcasts for free. To say nothing of what they might think of the broadcasts that deal with the what ifs surrounding our discovery of their excursions.
I suppose I wonder what void does this willingness to believe in E.T. fill? Does God seem remote and unbelievible to some, and they have this need to believe in something greater? Or does it flow from our secret belief that we are infinitely fascinating and deserving of attention? Now that we know our tiny blue home isn't the geographic center of the universe are some people trying to reinvent it as the social center?
--Jimmy has fancy plans; and pants to match.
Well, since we have yet to discover what exactly makes us sentient
This is not strictly speaking true evolutionary science has a pretty good hypothesis.
Evoloution is a balance between Natural Selection (survival) and Sex Selection (propagation). When a species achieves top carnivore status it is no longer predated it become possible to seek out alternative strategies. Natural selection become relatively less important than sexual selection. One such strategy is the development of intelligence, communications ability, even altruism. In the same way that Natural Selection can cause an arms race, Sex Selection drives a similar race in intelligence, communications ability and altruism.
A similar features appear in many top carnivores, Whales and African Wild Dogs for two examples exhibit a very high intelligence, unusual communication abilites and altruism.