Nathan Taylor introduces the (in my eyes) most comfortable explanation for the Fermi paradox. While I think it's a perfectly reasonable explanation, I also wanted to add my own from a while back: http://jcfrei.com/my-take-on-the-fermi-paradox
So why is it inevitable that any civilization that can evolve to the point of space travel will necessarily have the desire and capability to continue to expand before extinction? We've only been around a relatively short time and there is no certainty that we will be around long enough to be able to spread across the galaxy. If someone had told me in 1969 that 45 years later we would have lost the capability (or desire) to colonize the moon, I would have thought it highly unlikely. But here we are.
I'm not sure what "we" have lost the desire to colonize the moon, it's just that the costs far outweigh the benefits. One of the points of his article is that it will eventually be possible to build self-replicating robots that will themselves colonize the galaxy. In fact, it will become trivial to do so -- yet there are none that we've observed from other civilizations.
maybe I'm missing it, but I don't see any significant outlays of funds for colonizing the moon yet. Lots of plans an good intentions, but no will yet. And yes, it may be possible to cheaply build self-replicating robots that colonize the galaxy. But that, too, is just a speculative prediction. We're not there yet. And just as governments decided it would be better to spend their wealth on terrestrial matters rather than the moon, it remains to be seen how long it will take to make those self-replicating colonizing robots in large enough numbers to make a dent in the galaxy.
It might easily have gone the other way. The Orion project lost out largely due to politics. If we had built those, we'd probably have an industrial infrastructure in space by now.
So, assume only one of ten civilizations take the expanding choice early. That is still not enough to explain the Fermi paradox.
Unrelated rant/argument:
As a civilization we should publicise "anti heroes" as much as heroes. Those who e.g. destroy something beautiful for short sighted political votes.
Not just the politicians which destroyed our space future. Another example is the present political leaders in Iraq which seems to have caused a war just because they wanted to steal more without interruptions. Would they have done that if they knew their children and grand children would be in the news when their private jets land somewhere? ("Blood billionaires land in XXX, all better restaurants take a holiday. Sorry honest rich people".)
Edit: About the Fermi paradox -- the simplest answer ought to be that there are ET probes somewhere in the solar system and probably with lots of sensors floating around. The scary part is that they don't talk to us; that implies they are studying us and will clean the local infestation out before it spreads from the solar system.
Edit 2: The full argument (I didn't see it in the article?) is that there almost certainly will be lots of civilizations in the galaxy. We have no idea if we are among the first ten or among the second thousand. So statistics say we should probably be in the middle -- there are lots before we existed, we just can't detect them.
Evolution doesn't ensure advancement in the sense of greater capabilities or greater longevity or long-term survival either. Most species on this planet have gone extinct. What's to say that species capable of altering their world don't have a higher risk of catastrophic failure. The time scales are large and there's no evidence to make a strong assertion that we as a species will be around long enough so that we can colonize galaxies. There is an assumption that advanced civilizations will last for long periods of time. It's not clear to me that's valid. And what time scale is needed for galactic colonization? Why should that be different elsewhere?
Maybe 10-90% of technological species do make themselves extinct by a nuclear war or an environmental catastrophe. It isn't enough. To explain the Fermi paradox needs a big killer, like an innocent looking physics experiment that sterilizes a solar system.
My point was that we could already be more than a one planet civilization. So all the eggs aren't in one basket.
To be clear: That we already could be an interplanetary culture implies that _if_ there is a big killer that explains the Fermi paradox, it is either big enough to take out a solar system -- or it is behind us.
The next stop for spreading to the galaxy would be to get outside the solar system. The good part is that the Oort cloud etc is a good training stop over. And it would also insulate humanity there from what happens closer to the sun.
(And directly a civilization is interstellar, then it really are multiple cultures (communication lag etc). Those will at least partly be "evolved"/selected for tendency to spread.)
Lots of other people since at least Fermi discussed time scales for spreading in a galaxy, it is an old discussion. If you really can't find good references comment and I'll check the usual suspects for references (centauri-dreams.org).
Ah yes, gamma ray bursts got less common because of changing star formation rates? Really interesting.
I had missed the full argument. [Embarrassing :-)] The one I had seen was that closer to the galaxy centre there would be a higher frequency of supernovas per cubic light year, while too far out there would be too little of the heavier elements from supernovas.
If orion had politically one out and been weaponized it would make current MIRV technology look like a BB gun. Threat of it's development might have triggered a preventative first strike. You can make up all kinds of hypotheticals for either way.
See my parallel answer to 'molbioguy'. I would argue against your point (mainly, you don't need that with icbms + fusion bombs; more than a factor of ten in killing the enemy is a waste of money), but it isn't relevant to my point regarding the Fermi paradox.
Our history is filled with explorers and frontiersmen. We've grown to fill the world. We climb mountains and explore valleys. We cross oceans and fly around the world as soon as we know how.
The resources required to traverse interstellar distances are astronomically greater than terrestrial travel (pun intended). Most species die out. How long do you believe it will take to have human explorers on the nearest extrasolar planet. And that's the easiest, closest one. Then think about how many species go extinct on this planet. There's no certainty that we will survive long enough to explore that far.
Both halves of this statement are true: our capabilities and our appreciation of the difficulties have increased, and the Apollo missions were cold-war stunts---we never had the capability to colonize the moon.
The sad part is that we don't seem to have the interest either.
”In his article Dobzhanksy turned Sagan’s argument on its head. Dobzhansky cited the fact that of the more than two million species living on Earth only one had evolved language, extragenetically transmitted culture, and awareness of self and death, as proof that it is “fatuous” to hold “the opinion that if life exists anywhere else it must eventually give rise to rational beings.”“
I find this interesting because some scientists are open to the fact that dolphins[1] and elephants[2] may be significantly more intelligent than we previously supposed, and possibly as intelligent as humans. The difficulty lies in defining exactly what intelligence is - and how we measure it in other animals.
That in turn leads to more questions. Suppose that there is, in fact, at least 3 human-level sentient species on our own planet. Observe: only one of them have developed tools to the extent that space travel is a problem that we're trying to solve. Perhaps the reality is that there are as many intelligent species as astronomers posit - maybe multiple species per planet! - but almost all of them have no interest in exploring and settling on other planets.
Other animals also make simple food gathering tools or construct simple dwellings.
However, humans seem to have had a qualitative impact on the planet due to the quantity of things that they imagine and build. Perhaps the capacity for written language gives us the ability to recursively combine our tool building in layers? (not that reading and writing is required, but simply using that as a indicator that the species in general is capable of such permutation of ideas)
Without reading and writing I think the whole 'Standing on the shoulders of giants' thing falls apart because you must be directly associated with the 'giant'. How do you transmit the ideas of an Einstein between generations of normals?
Agreed, but it's possible, up to a point: oral history, apprenticeship, observation all serve. It is much less efficient, much less reliable, and probably impractical for higher-order things (such as theories of relativity) but it does work as a bootstrap. Human culture did well enough for a long time before writing.
I think a bigger reason that intelligent animals haven't progressed as far as us (qualify 'progress' however you like) is more to do with evolutionary pressure from humans changing the environment faster than they can adapt to it. That extends to populations of humans at different stages of societal evolution as well: cultures are snuffed out very quickly when more advanced groups make their presence felt.
The speciesism in the article struck me as an odd centrality. We are also in a small window between ice ages, there could have been and possibly be in the future other intelligent life on this planet. Depending how far you want to go, Homosapiens have displaced other intelligent hominids.
Crows might have language. Pigs are hella smart. Octopus are extremely intelligent from a purely genetic standpoint, they have no socialization with their parents. And many animals hunt in packs, including squid. What intelligent animals does our existence displace?
I thought that was a good idea poorly worded. It appears that other animals do have language, culture and awareness of death, but no other animal has built radios (or even uses fire as far as I know.) So I don't know why he chose that example.
I don't believe that life, even highly intelligent life, is rare in the universe. But I'd bet a life form that chooses to build giant radio telescopes is quite uncommon. We are freaks of the galaxy.
According to contemporary cosmological estimates, the earth has been around for the latter 1/3 of the universe's age. Even given that life-bearing planets must be at least second generation stars, and conservatively saying that it should take about as long as earth is around for the first generation to go (not true) the universe is already fairly old.
Interestingly, life evolved on earth in the first billion years. That's incredibly fast. Arguably, life is inevitable whereas intelligent life might not be so. Multicellularity didn't come about till the most recent billion...
When approaching the Fermi paradox astrobiologists usually use the principle of convergent evolution [1], where multiple types of life will evolve similar features because of similar environmental pressures. (the application is the development of intelligence.) I'm a big fan of this, because it affirms my hope that life exists elsewhere. But unfortunately we don't really know what "life" and "intelligence" is -- an intelligent dolphin might never think or desire to leave the ocean, and an intelligent four-legged creature might never think to look up at the sky and wonder, the way that humans have always done.
The Milky Way is around 100000 light years wide. Humans have had the capability to look for ETs (as we expect them to sound) for what, 40-ish years?
Considering the time and space scales involved, it's hard for me to believe we have enough data for a conclusion either way, particularly without assuming faster than light travel and also given the 'youth' of the universe. Even if we did assume faster than light travel, it seems like you'd have to have insane levels of population growth to make it all that far from home without going very very slowly. And if you do start moving out, would it really be worth trying to signal home if it would take 1000 years or 100 years to reach 'home?'
Another issue I have is what I'd term anthropological environmental constraints as applied to aliens, namely it's quite conceivable that some home worlds would not offer the resources needed to make it into space, or would contain them in an inaccessible way. If a race of Einstein-like aliens is stuck on the a planetary equivalent of a desert island we'll never hear from them.
As far as the self replicating robots go, I see two issues: first, it should still be pretty slow without light speed travel, and second, if these robots don't have a realistic chance of reporting back to their source civilization, why would the civilization even bother? (We can barely understand the ancient Maya. When a robot returns after 30 million years, this problem seems like it'd only be exacerbated. Likewise, the time horizon is so far out it'd be unlikely a particular group would see an ROI argument to attempt it other than as a hobby.)
So I really feel like it's a bit premature to draw conclusions about the 'Fermi Paradox.'
If you could travel at only 1% of c you could cross from one side to the other in only 10 million years. At evolutionary time scales you could have been there and back three times since the dinosaurs disappeared. It's not hard to imagine that within a couple of centuries we could start a self-replicating robot project that would explore the entire galaxy in that time frame. We'd have the complete results within a mere 100,000 years of completion.
If you assume that aliens with the intelligence and drive to achieve star travel are common, it becomes pretty laughable to think that NONE of them had the curiosity to explore or meet other species or eradicate the competition. If you're arguing that we're the 5th such species in the galaxy then... maybe.
If you are limited to travel at 1% of c, communications at c, and self replicating probes, you'll have to wait many times 10 million years before you get more than a tiny sampling of responses from your probes.
If you assume Humans are intelligent with a drive to achieve star travel, then why haven't we?
We barely visit the planets in our own solar system and we are continually reducing our radio waves. So unless someone happened to be looking at us at the right time. They might assume we don't exist.
All we know is that in the incredibly tiny parts of the universe we have looked, we haven't seen signs of US. We could have seen several signs of ET and never realized it.
Doesn't the existence of organic lifeforms (obviously an assumption which can be debated) almost surely guarantee the presence of fossil fuels? Given the average time evolution takes to produce intelligent life, won't there most likely be sufficient deceased organic matter which can be turned into a source of fuel?
Absolutely not. Just recently a bacteria (or maybe an archae, I can't find an article) was discovered that efficiently breaks organic matter in anaerobic conditions. There is a sharp decrease in the amount of coal formed after that bacteria evolved a few dozen million years ago.
It's just an accident, that we are the 1st life form capable of extracting the energy from fossil fuels.
I remember reading that most of the fossil fuels on earth were deposited before mushrooms and other fungi evolved which break down organic matter. Before they existed, organic material did not decay nearly as fast as it does now, so it would just pile up. That's why there is so much fossil fuel around, but it probably wont ever be replenished to the same levels.
I forget where I read this, so I could be misremembering. In any case, there's no guarantee that fossil fuels will exist.
You are offering three resolutions of the Fermi Paradox. All three of them are the form: some intelligent species will be unable/unwilling to communicate with us. This is incorrect. The resolution of the paradox have to be: ALL intelligent species are unable/unwilling to communicate with us.
You can try to take your probabilistic resolutions and multiply them all together to show a very low probability. But then you need an upper bound on the expected number of intelligent species. Which keeps increasing (number of Earth like planets).
(Mayans were not trying to communicate with anyone else. Those robots will be trying to. There is probably enough structure in physics and math to be the basis of communication with any alien species.)
My favorite resolution is the one where our solar system, having developed sentience, is under the protection of the galactic equivalent of the EPA, sort of a 'you can't go in there because they haven't finished hatching' sort of thing.
Please tell me that there's a short story on this. I'm envisioning a cigar-chomping developer trying to lobby for building on "prime real estate" while some nutball hippie lawyer is working tirelessly to stop him while his colleagues deride him for caring so much about "carbon-based animals."
"Well, we've done it billions of times before. What makes these ones any different?"
"It was wrong the last billions of times we did it, too."
"Well, you're living on a planet that was taken from some lesser species. And so was the planet your forefathers settled on. And them before that, and them before that. This is the natural course of things. Sucks to be them."
NB The Culture has the opposite of the Star Trek Federation's Prime Directive - they justify to themselves the hedonistic paradise that 99% of their population (biologicals and machines) live in through the interference of their Contact and Special Circumstances sections in the affairs of "lesser" civilisations.
I don't think I'm offering resolutions. I'm saying that we have far too limited amounts of information to resolve things in one direction or the other.
(On the Mayan aside, I guess I do agree that there will be some basis for getting information from a returned probe, but after millions of years I doubt the home civilization will even remember that they were the ones who sent the probes out to begin with. I guess to be more precise, I expect that the home civ will have been replaced by new civs many times over.)
On the probe side, if they return to home there's also no reason to expect them to signal, and seeing one would be unlikely considering we can barely even find asteroids that pose a risk of collision with Earth. So I guess there's also some possibility that there are alien probes slipping through the solar system every so often and we just haven't been able to observe them.
You are arguing (or you were already in the last comment) that there is something 'wrong' with humans which is the reason that we have been unable to see aliens. I think this is a much stronger argument. As far as I can see, this line of reasoning only requires making two arguments about aliens: they are at most Kardashev Type II and they are not actively broadcasting their existence using EM waves.
I don't buy your arguments about memories of probes/ciz at all. I am extrapolating from human civilization. We haven't forgotten much and plan on remembering everything in the future.
Then tell me we should have been contacted by now. Even with light speed travel (not faster), we're talking 13 billion years.. and this isn't including the time necessary for the civilization to advance that far.
The distance is staggering.
edit: rereading Fermi's paradox it seems they are only talking about the Milky Way, which I am not. But even if the chances of intelligent life forming are 1 in a billion.. the universe is so large that there could still be many civilizations out there (that we might never see).
Which is my point of view.. there probably is intelligent life out there but it's unlikely we will ever run into it.
The Fermi Paradox is nothing of the sort. It is simply an expression of how thoroughly ignorant we are about the nature of advanced technological and interstellar life, no more. It might mean that we are ignorant of the short lifespan or extreme rarity of technological civilizations, but we have insufficient data to support conclusions along those lines. It is more likely that our surmises about the nature of colonizing interstellar civilizations are just fundamentally in error in some way we cannot even really understand today in the same way that someone in the year 1500 BC would not truly understand the internet or antibiotics or electricity produced by way of nuclear fission and so wouldn't understand their impact on our way of life.
It is not really the same because any of your examples would not supposedly coincide with a 1500 BC civ. So none of it would be observable. You would only be talking about stuff in the way distant future that did not exist at the time and only a time traveler would be able to describe.
The Fermi Paradox is a discussion based on that there currently SHOULD be advanced tech and colonized civs at the SAME time we are and have been looking for them. So where are they?
Even ruling out a Earth or even Solar System visit, they should have evidence out there that can be seen. Some sort of energy signature, a space station, satellite, giant mothership as it checks out life detected as us. SOMETHING. The Fermi Paradox says, by now, there should have been at least one Type III civ in our galaxy given how old it is and they would eventually tip their hat to their existence, unless they purposely try and are able to hide themselves.
I take a Kurzwielian view. There is probably a significant transition in the physical bodies of an intelligent lifeform past a certain point of evolution. and a dramatic increase in cognitive ability.
Fermi's Paradox makes more sense when you theorize that ET transforms its biology into a computational substrate prior to gaining the ability to travel between stars, as will likely happen with us. When it does this it turns into something we won't even recognize, something likely a million times smaller than us due to miniaturization, and a trillion times smarter. Even if they are around they probably don't have the patience to interact with us, dumb as we are and with minds that travel 10^5 or so slower.
It is actually, he says roughly the same thing about miniaturization; that any post-biological extraterrestrial life is possibly microscopic and not something we would easily recognize.
I don't think post-biological ET necessarily turns all the energy and matter in its galaxy to computronium either. It's possible that an amount of matter on the order of a planet or less is more than enough to satisfy. The same postulation can function as an attempt to explain the absence of Dyson spheres or anything of the like.
When we think of theoretical star-faring advanced ETs we anthropomorphize. We're imagining them on the same temporal and spatial scales which we occupy, but they are possibly many orders of magnitude smaller and faster. So this is a Kurzwielian view in that it extrapolates from the patterns that he identifies.
A friend of mine is professor in genetics in Columbia university. He spent many years experimenting around the RNA world hypothesis and his opinion is that the origin of Earth life was a very unlikely event. Once in a Universe unlikely.
I think this piece makes a very good point and makes it very well.
One thing I wonder about, vis-a-vis SETI-style projects, is the idea the humans could identify extraterrestrial communication even after receiving it. I'm fine with assuming that extraterrestrial life is attempting to communicate with us and is using technologies we'd be familiar with (eg., electromagnetic radiation transmitting binary data) — until we ourselves develop some other technology, this is our safest assumption. But we should also assume that a sufficiently-advanced lifeform would transmit data near the information theoretical maximum efficiency, and of course, maximally-efficient data will appear entirely random to an observer who has no means to make sense of it.
* Snarky comment numero uno: If I understand the author and the Less Wrong, Bayesian, weirdish probability thought process, I suspect that the correct conclusion to this article is that humanity doesn't actually exist.
* Snarky comment numero dos: The Drake equation includes a term:
"L = the length of time for which such civilizations release detectable signals into space"
(I originally heard that as the length of time before or probability of a civilization destroying itself. Yay, collapse of the Soviet Union! Progress!)
Anyway, I believe that humanity is no longer trying to outshine stars with our radio broadcasts, or at least that we are not getting any brighter. So here's a question or two for the author's model:
What is the probability that a civilization will release self-replicating probes? (Granted, that anything that can be done will be done, must be done by someone, sometime.) What is the probability that you will be able to detect such probes if one was standing next to you right now? I'll just note that in a comment on another article, the author writes, "But if 1000 years from now we start sending probes out to explore and replicate across millions/billions of stars. We’d have detectable radio traffic and other signs that SETI would pick up."
Snarky comment numero tres: So, evolutionary biologists believe that Darwinian evolution, if it leads to intelligent life, further inevitably leads to self-replicating robotic space probes?
I suspect the only reasonably hard conclusion that biology lends to the goofy debate is that life, not necessarily intelligent life, is everywhere, given that our one anecdote here indicates that life developed incredibly quickly on the scale of planetary existence.
A few people in different threads here talk about self-replicating robots or probes. The way they write, it seems as though we already have the technology to make them - which comes as a surprise to me.
So: for those of you who have talked about self-replicating machinery - where exactly are we at with that technology? And why are so many people sure it's more attainable than, say, faster-than-light travel?
I think it just seems superficially attainable given things like 3-D printers and continuing improvements in AI, forget questions like how it fuels itself.
Yeah, we're talking about fully-automated, fully self-repairing facilities that encompass the entire vertical industrial production infrastructure - mining, refinement, raw material production, all the way to assembly of finished good and installation of those goods into the infrastructure.
We're not remotely close to having that on Earth, let alone as self-contained spacecraft.
Taking a cynical view of the paradox, saying that not having already detected ET means that ET couldn't exists, opens a new paradox. What if every intelligent civilization looked at the same problem and reached the cynical point of view: why bother looking?
And what's to say we're not aliens ourselves? That Prometheus movie hinted at the possibility, so did Star Trek. Both point to an original creator that uses simple biology and knowledge of evolution to seed planets with life and let it grow. Modern astrobiology, as documented in the recent Cosmos reboot, thinks that life has already been traversing the galaxy on space rocks; crashing into planets in an ice ball and taking hold where it can. While not intelligent by human standards, it still spreads ET life. With the time scales involved, it seems like space rocks with simple life on them might be spreading ET fairly evenly through our galaxy and beyond.
As smart as we are, we have only recently been able to hurtle some space junk out of our solar system and into deep space. The distances involved and the limitations of our current understanding of physics make it seem likely that we wouldn't be in direct contact already. It's taken 2 generations for Voyager 1 to travel that far.
Using ourselves as the perfect example, our own broadcasts haven't reached very far into our own galaxy. If we are typical and our understanding of physics is reasonably accurate, there could be numerous human-like civilizations broadcasting and sending out probes constantly and we just haven't waited long enough -- the distances are too vast for us to have heard them. Or worse, we're not intelligent enough yet to listen to the broadcasts that are being sent to us already.
I say we build these magical self-replicating probes and send them out and hope we don't accidentally create the Borg. The only way to beat the paradox is to play along. And if we don't find anything, then we'd better get to colonizing!
I've read two books on this and my current favored solution to the Paradox is Supernovae and/or Gamma Ray Bursts. Particularly GRB as they have to ability to sterilize whole galaxies. There is a possibility even Earth has already faced one 440m years ago.
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[ 2.8 ms ] story [ 101 ms ] threadSo, assume only one of ten civilizations take the expanding choice early. That is still not enough to explain the Fermi paradox.
Unrelated rant/argument:
As a civilization we should publicise "anti heroes" as much as heroes. Those who e.g. destroy something beautiful for short sighted political votes.
Not just the politicians which destroyed our space future. Another example is the present political leaders in Iraq which seems to have caused a war just because they wanted to steal more without interruptions. Would they have done that if they knew their children and grand children would be in the news when their private jets land somewhere? ("Blood billionaires land in XXX, all better restaurants take a holiday. Sorry honest rich people".)
Edit: About the Fermi paradox -- the simplest answer ought to be that there are ET probes somewhere in the solar system and probably with lots of sensors floating around. The scary part is that they don't talk to us; that implies they are studying us and will clean the local infestation out before it spreads from the solar system.
Edit 2: The full argument (I didn't see it in the article?) is that there almost certainly will be lots of civilizations in the galaxy. We have no idea if we are among the first ten or among the second thousand. So statistics say we should probably be in the middle -- there are lots before we existed, we just can't detect them.
Maybe 10-90% of technological species do make themselves extinct by a nuclear war or an environmental catastrophe. It isn't enough. To explain the Fermi paradox needs a big killer, like an innocent looking physics experiment that sterilizes a solar system.
My point was that we could already be more than a one planet civilization. So all the eggs aren't in one basket.
To be clear: That we already could be an interplanetary culture implies that _if_ there is a big killer that explains the Fermi paradox, it is either big enough to take out a solar system -- or it is behind us.
The next stop for spreading to the galaxy would be to get outside the solar system. The good part is that the Oort cloud etc is a good training stop over. And it would also insulate humanity there from what happens closer to the sun.
(And directly a civilization is interstellar, then it really are multiple cultures (communication lag etc). Those will at least partly be "evolved"/selected for tendency to spread.)
Lots of other people since at least Fermi discussed time scales for spreading in a galaxy, it is an old discussion. If you really can't find good references comment and I'll check the usual suspects for references (centauri-dreams.org).
As I've mentioned elsewhere: Gamma Ray Bursts
I had missed the full argument. [Embarrassing :-)] The one I had seen was that closer to the galaxy centre there would be a higher frequency of supernovas per cubic light year, while too far out there would be too little of the heavier elements from supernovas.
Why would you expect space to be any different?
The sad part is that we don't seem to have the interest either.
”In his article Dobzhanksy turned Sagan’s argument on its head. Dobzhansky cited the fact that of the more than two million species living on Earth only one had evolved language, extragenetically transmitted culture, and awareness of self and death, as proof that it is “fatuous” to hold “the opinion that if life exists anywhere else it must eventually give rise to rational beings.”“
I find this interesting because some scientists are open to the fact that dolphins[1] and elephants[2] may be significantly more intelligent than we previously supposed, and possibly as intelligent as humans. The difficulty lies in defining exactly what intelligence is - and how we measure it in other animals.
That in turn leads to more questions. Suppose that there is, in fact, at least 3 human-level sentient species on our own planet. Observe: only one of them have developed tools to the extent that space travel is a problem that we're trying to solve. Perhaps the reality is that there are as many intelligent species as astronomers posit - maybe multiple species per planet! - but almost all of them have no interest in exploring and settling on other planets.
[1]http://www.dolphins-world.com/dolphin-intelligence/ [2]http://en.wikipedia.org/wiki/Elephant_cognition
However, humans seem to have had a qualitative impact on the planet due to the quantity of things that they imagine and build. Perhaps the capacity for written language gives us the ability to recursively combine our tool building in layers? (not that reading and writing is required, but simply using that as a indicator that the species in general is capable of such permutation of ideas)
I think a bigger reason that intelligent animals haven't progressed as far as us (qualify 'progress' however you like) is more to do with evolutionary pressure from humans changing the environment faster than they can adapt to it. That extends to populations of humans at different stages of societal evolution as well: cultures are snuffed out very quickly when more advanced groups make their presence felt.
Crows might have language. Pigs are hella smart. Octopus are extremely intelligent from a purely genetic standpoint, they have no socialization with their parents. And many animals hunt in packs, including squid. What intelligent animals does our existence displace?
I don't believe that life, even highly intelligent life, is rare in the universe. But I'd bet a life form that chooses to build giant radio telescopes is quite uncommon. We are freaks of the galaxy.
Interestingly, life evolved on earth in the first billion years. That's incredibly fast. Arguably, life is inevitable whereas intelligent life might not be so. Multicellularity didn't come about till the most recent billion...
http://en.wikipedia.org/wiki/Convergent_evolution
Considering the time and space scales involved, it's hard for me to believe we have enough data for a conclusion either way, particularly without assuming faster than light travel and also given the 'youth' of the universe. Even if we did assume faster than light travel, it seems like you'd have to have insane levels of population growth to make it all that far from home without going very very slowly. And if you do start moving out, would it really be worth trying to signal home if it would take 1000 years or 100 years to reach 'home?'
Another issue I have is what I'd term anthropological environmental constraints as applied to aliens, namely it's quite conceivable that some home worlds would not offer the resources needed to make it into space, or would contain them in an inaccessible way. If a race of Einstein-like aliens is stuck on the a planetary equivalent of a desert island we'll never hear from them.
As far as the self replicating robots go, I see two issues: first, it should still be pretty slow without light speed travel, and second, if these robots don't have a realistic chance of reporting back to their source civilization, why would the civilization even bother? (We can barely understand the ancient Maya. When a robot returns after 30 million years, this problem seems like it'd only be exacerbated. Likewise, the time horizon is so far out it'd be unlikely a particular group would see an ROI argument to attempt it other than as a hobby.)
So I really feel like it's a bit premature to draw conclusions about the 'Fermi Paradox.'
If you assume that aliens with the intelligence and drive to achieve star travel are common, it becomes pretty laughable to think that NONE of them had the curiosity to explore or meet other species or eradicate the competition. If you're arguing that we're the 5th such species in the galaxy then... maybe.
How long is your curiosity willing to wait?
We barely visit the planets in our own solar system and we are continually reducing our radio waves. So unless someone happened to be looking at us at the right time. They might assume we don't exist.
All we know is that in the incredibly tiny parts of the universe we have looked, we haven't seen signs of US. We could have seen several signs of ET and never realized it.
Absolutely not. Just recently a bacteria (or maybe an archae, I can't find an article) was discovered that efficiently breaks organic matter in anaerobic conditions. There is a sharp decrease in the amount of coal formed after that bacteria evolved a few dozen million years ago.
It's just an accident, that we are the 1st life form capable of extracting the energy from fossil fuels.
You can try to take your probabilistic resolutions and multiply them all together to show a very low probability. But then you need an upper bound on the expected number of intelligent species. Which keeps increasing (number of Earth like planets).
(Mayans were not trying to communicate with anyone else. Those robots will be trying to. There is probably enough structure in physics and math to be the basis of communication with any alien species.)
"Well, we've done it billions of times before. What makes these ones any different?"
"It was wrong the last billions of times we did it, too."
"Well, you're living on a planet that was taken from some lesser species. And so was the planet your forefathers settled on. And them before that, and them before that. This is the natural course of things. Sucks to be them."
I'd read that.
http://www.youtube.com/watch?v=IRl9D_agLbU
NB The Culture has the opposite of the Star Trek Federation's Prime Directive - they justify to themselves the hedonistic paradise that 99% of their population (biologicals and machines) live in through the interference of their Contact and Special Circumstances sections in the affairs of "lesser" civilisations.
(On the Mayan aside, I guess I do agree that there will be some basis for getting information from a returned probe, but after millions of years I doubt the home civilization will even remember that they were the ones who sent the probes out to begin with. I guess to be more precise, I expect that the home civ will have been replaced by new civs many times over.)
On the probe side, if they return to home there's also no reason to expect them to signal, and seeing one would be unlikely considering we can barely even find asteroids that pose a risk of collision with Earth. So I guess there's also some possibility that there are alien probes slipping through the solar system every so often and we just haven't been able to observe them.
I don't buy your arguments about memories of probes/ciz at all. I am extrapolating from human civilization. We haven't forgotten much and plan on remembering everything in the future.
Go through these images: http://imgur.com/a/3Y6dB#NynTc
Then tell me we should have been contacted by now. Even with light speed travel (not faster), we're talking 13 billion years.. and this isn't including the time necessary for the civilization to advance that far.
The distance is staggering.
edit: rereading Fermi's paradox it seems they are only talking about the Milky Way, which I am not. But even if the chances of intelligent life forming are 1 in a billion.. the universe is so large that there could still be many civilizations out there (that we might never see).
Which is my point of view.. there probably is intelligent life out there but it's unlikely we will ever run into it.
The Fermi Paradox is a discussion based on that there currently SHOULD be advanced tech and colonized civs at the SAME time we are and have been looking for them. So where are they?
Even ruling out a Earth or even Solar System visit, they should have evidence out there that can be seen. Some sort of energy signature, a space station, satellite, giant mothership as it checks out life detected as us. SOMETHING. The Fermi Paradox says, by now, there should have been at least one Type III civ in our galaxy given how old it is and they would eventually tip their hat to their existence, unless they purposely try and are able to hide themselves.
Fermi's Paradox makes more sense when you theorize that ET transforms its biology into a computational substrate prior to gaining the ability to travel between stars, as will likely happen with us. When it does this it turns into something we won't even recognize, something likely a million times smaller than us due to miniaturization, and a trillion times smarter. Even if they are around they probably don't have the patience to interact with us, dumb as we are and with minds that travel 10^5 or so slower.
1. A singularity happened in a human civilization, that was 1st to evolve in it's galaxy.
2. That civilization turned all the energy and matter in that galaxy into computronium.
3. They run a 10^70 simulations and we are inside one of those.
I don't think post-biological ET necessarily turns all the energy and matter in its galaxy to computronium either. It's possible that an amount of matter on the order of a planet or less is more than enough to satisfy. The same postulation can function as an attempt to explain the absence of Dyson spheres or anything of the like.
When we think of theoretical star-faring advanced ETs we anthropomorphize. We're imagining them on the same temporal and spatial scales which we occupy, but they are possibly many orders of magnitude smaller and faster. So this is a Kurzwielian view in that it extrapolates from the patterns that he identifies.
If that turns out to be correct - I'll eat my own brain.
One thing I wonder about, vis-a-vis SETI-style projects, is the idea the humans could identify extraterrestrial communication even after receiving it. I'm fine with assuming that extraterrestrial life is attempting to communicate with us and is using technologies we'd be familiar with (eg., electromagnetic radiation transmitting binary data) — until we ourselves develop some other technology, this is our safest assumption. But we should also assume that a sufficiently-advanced lifeform would transmit data near the information theoretical maximum efficiency, and of course, maximally-efficient data will appear entirely random to an observer who has no means to make sense of it.
* Snarky comment numero dos: The Drake equation includes a term:
"L = the length of time for which such civilizations release detectable signals into space"
(I originally heard that as the length of time before or probability of a civilization destroying itself. Yay, collapse of the Soviet Union! Progress!)
Anyway, I believe that humanity is no longer trying to outshine stars with our radio broadcasts, or at least that we are not getting any brighter. So here's a question or two for the author's model:
What is the probability that a civilization will release self-replicating probes? (Granted, that anything that can be done will be done, must be done by someone, sometime.) What is the probability that you will be able to detect such probes if one was standing next to you right now? I'll just note that in a comment on another article, the author writes, "But if 1000 years from now we start sending probes out to explore and replicate across millions/billions of stars. We’d have detectable radio traffic and other signs that SETI would pick up."
Snarky comment numero tres: So, evolutionary biologists believe that Darwinian evolution, if it leads to intelligent life, further inevitably leads to self-replicating robotic space probes?
I suspect the only reasonably hard conclusion that biology lends to the goofy debate is that life, not necessarily intelligent life, is everywhere, given that our one anecdote here indicates that life developed incredibly quickly on the scale of planetary existence.
So: for those of you who have talked about self-replicating machinery - where exactly are we at with that technology? And why are so many people sure it's more attainable than, say, faster-than-light travel?
We're not remotely close to having that on Earth, let alone as self-contained spacecraft.
And what's to say we're not aliens ourselves? That Prometheus movie hinted at the possibility, so did Star Trek. Both point to an original creator that uses simple biology and knowledge of evolution to seed planets with life and let it grow. Modern astrobiology, as documented in the recent Cosmos reboot, thinks that life has already been traversing the galaxy on space rocks; crashing into planets in an ice ball and taking hold where it can. While not intelligent by human standards, it still spreads ET life. With the time scales involved, it seems like space rocks with simple life on them might be spreading ET fairly evenly through our galaxy and beyond.
As smart as we are, we have only recently been able to hurtle some space junk out of our solar system and into deep space. The distances involved and the limitations of our current understanding of physics make it seem likely that we wouldn't be in direct contact already. It's taken 2 generations for Voyager 1 to travel that far.
Using ourselves as the perfect example, our own broadcasts haven't reached very far into our own galaxy. If we are typical and our understanding of physics is reasonably accurate, there could be numerous human-like civilizations broadcasting and sending out probes constantly and we just haven't waited long enough -- the distances are too vast for us to have heard them. Or worse, we're not intelligent enough yet to listen to the broadcasts that are being sent to us already.
I say we build these magical self-replicating probes and send them out and hope we don't accidentally create the Borg. The only way to beat the paradox is to play along. And if we don't find anything, then we'd better get to colonizing!
http://www.youtube.com/watch?v=7HIokbQMHB8