Comment of the Day: Advanced ET Civilizations May Be Impossible to Detect (Holiday Weekend Feature)
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Advanced ET Civilizations May Be Impossible to Detect (Holiday Weekend Feature)




The Fermi paradox is the apparent contradiction between high estimates of the probability of the existence of extraterrestrial civilizations and the lack of evidence for, or contact with, such civilizations. As Enrico Fermi asked if the Universe is conducive to intelligent life, “Where is everybody?”

A new answer proposed by Adrian Kent of the University of Cambridge and Perimeter Institute, is that extraterrestial life sufficiently advanced to be capable of interstellar travel or communication must be rare, since otherwise we would have seen evidence of it by now. This in turn is sometimes taken as indirect evidence for the improbability of life evolving at all in our universe.

“Intelligent species might reasonably worry about the possible dangers of self-advertisement and hence incline towards discretion” -- the “Undetectability Conjecture,” put forth by Beatriz Gato-Rivera, a theoretical physicist at the Instituto de Fisica Fundamental (previously Instituto de Matematicas y Fisica Fundamental) of the CSIC (Spanish Scientific Research Council) in Madrid. According to Gato-Rivera, we may find ourselves in a universe in which there exist intelligent technological civilizations but they have chosen to be undetectable, camouflaging themselves mainly for security reasons (because advanced civilizations could also be aggressive).

Evolutionary selection, acting on a cosmic scale," Kent adds. "tends to extinguish species which conspicuously advertise themselves and their habitats.”

“It often seems, Kent concludes, "to be implicitly assumed, and sometimes is explicitly argued, that colonising or otherwise exploiting the resources of other planets and other solar systems will solve our problems when the Earth’s resources can no longer sustain our consumption. It might perhaps be worth contemplating more seriously the possibility that there may be limits to the territory we can safely colonise and to the resources we can safely exploit, and to consider whether and how it might be possible to evolve towards a way of living that can be sustained (almost) indefinitely on the resources of (say) our solar system alone.”

In another take on the "Fermi Paradox," Stephen Hawking asks In his famous lecture on Life in the Universe: "What are the chances that we will encounter some alien form of life, as we explore the galaxy?"

If the argument about the time scale for the appearance of life on Earth is correct, Hawking says "there ought to be many other stars, whose planets have life on them. Some of these stellar systems could have formed 5 billion years before the Earth. So why is the galaxy not crawling with self-designing mechanical or biological life forms?"

Why hasn't the Earth been visited, and even colonized? Hawking asks. "I discount suggestions that UFO's contain beings from outer space. I think any visits by aliens, would be much more obvious, and probably also, much more unpleasant."

Hawking continues: "What is the explanation of why we have not been visited? One possibility is that the argument, about the appearance of life on Earth, is wrong. Maybe the probability of life spontaneously appearing is so low, that Earth is the only planet in the galaxy, or in the observable universe, in which it happened. Another possibility is that there was a reasonable probability of forming self reproducing systems, like cells, but that most of these forms of life did not evolve intelligence."

We are used to thinking of intelligent life, as an inevitable consequence of evolution, Hawking emphasized,  but it is more likely that evolution is a random process, with intelligence as only one of a large number of possible outcomes.

Intelligence, Hawking believes contrary to our human-centric existece, may not have any long-term survival value. In comparison the microbial world, will live on, even if all other life on Earth is wiped out by our actions. Hawking's main insight is that intelligence was an unlikely development for life on Earth, from the chronology of evolution:  "It took a very long time, two and a half billion years, to go from single cells to multi-cell beings, which are a necessary precursor to intelligence. This is a good fraction of the total time available, before the Sun blows up. So it would be consistent with the hypothesis, that the probability for life to develop intelligence, is low. In this case, we might expect to find many other life forms in the galaxy, but we are unlikely to find intelligent life."

Another possibility is that there is a reasonable probability for life to form, and to evolve to intelligent beings, but at some point in their technological  development "the system becomes unstable, and the intelligent life destroys itself. This would be a very pessimistic conclusion. I very much hope it isn't true."

Hawkling prefers another possibility: that there are other forms of intelligent life out there, but that we have been overlooked. If we should pick up signals from alien civilizations, Hawking warns,"we should have to be wary of answering back, until we have evolved" a bit further. Meeting a more advanced civilization, at our present stage, Hawking says, "might be a bit like the original inhabitants of America meeting Columbus. I don't think they were better off for it."

The Daily Galaxy via


I offer another possibility, at some point in any intelligent civilizations technological rise they gain the ability to hide themselves from the rest of the universe. Either by manipulating gravity, or some other form of quantum cloak. We ourselves are beginning to see the possibility of this in the form of passive camouflage. Using meta materials to become invisible.

Ugh i only read the bottom half before posting :/ but as the article states it makes perfect sense for advanced civilizations to hide themselves from other possibly hostile species as a form of protection and just as a precaution for studying another intelligent species. Star Trek was so ahead of its time, with regard to these ideas.

I agree with conclusion that intelligence don't exist very often. Maybe once a galaxy or more seldom.

I am strongly with the idea that intelligent life on our planet is just one of millions spreading around.

Everything else i am assuming for a forceful blindness.

@ Grezevoo Even if there is only 1 intelligent civilization per galaxy where you have over 100 billion stars per galaxy with some galaxies sporting nearer to a trillion stars. There are over 100 billion galaxies in the visible universe, maybe more. So even assuming you have only 1 species per galaxy, that's still 100 billion x 100 billion possible life sustaining solar systems. Which is probably a small estimate. We know that the building blocks of life are present more or less everywhere in the universe. The numbers just don't agree with you.

The distances are just too great for interstellar travel or communication. No civilization that will ever be able to overcome these 'obstacles'.

It's that simple.

It's amazing that people like you still exist George. History has taught us over and over again that impossibility is a matter of technological advancement (simple right?). We don't even have real space planes yet, and you've already dismissed interstellar travel completely. If everyone thought that way, we would still be living in caves. Shocking that such short-sightedness can be typed out on with a once-impossible computer on the magical internet. May the small-minded please keep your mouths shut, lest you delay our progression further.

The telephone, the atom bomb, the television, the camera, the automobile, the airplane, and every other major advancement in the history of mankind at one point or another was thought to be impossible. Until someone stop listening to the idiots saying it couldn't be done and did it. People like George will always exist. Thinking the world is flat until someone proves them wrong. George ever heard of teleportation?. It was science fiction only like 15 year ago. Now its a scientific fact.

As Lily Tomlin spoke in her one woman Broadway show Looking for Intelligent Life ... the fact that there has been no contact only proves how intelligent "they" are. And yes there is other life forms but their subtleties fall outside of the extremely limited human senses and technology. btw: Any advanced form would not need something so antiquated as a space ship.

I find it hard to believe that someone could call them self a scientist and state, without laughing, that life, intelligent or otherwise, must be rare in the universe because we haven't found evidence of it. How long have we been looking? We have barely scratched the surface.

maybe ufo are they. or maybe when you may travel or speak long distances maybe you can leave this universe with that tehnology. or prometheus..:)

Hawklin >< love it

Somebody out there knows we are here. We are already able to detect "habitable planets" light years away at our stage of technological advancement. Anything sufficiently advanced in our galaxy would know we are here. The worst possible guess for me is that, we arent worth anything to a true advanced species, like us compared to ants.

Either by manipulating gravity, or some other form of quantum cloak. We ourselves are beginning to see the possibility of this in the form of passive camouflage. Using meta materials to become invisible.


Watch a fish foraging
on submerged, open shore,
investigating its environment.

If what attracts its curiosity
reveals camouflaged hostility,
it quickly swims away.

An alien intelligence engaged in exploration
might view Earth as poisonous and stinging,
and steer clear, leaving us alone.

There IS actually ample evidence of extraterrestrial visitation, but it all gets dismissed because we just KNOW it's not true.

We're like deep-sea fish denying the existence of life outside the ocean, dismissing the tales of vast "ships" floating at the surface because the fish that have seen them are unreliable (of course they are: ships do not exist, so you become unreliable when you talk about them), and taking our circular reasoning as proof that deep-sea fish are the only creatures alive in the universe.

After all, if these "ships" and the "humans" in them were real, they would've already given us deep-sea fish the secret of quick inter-oceanic travel (pacific to atlantic in a week!? impossible) and nuclear power. Plus, what purpose could they possibly have if theyve been in our waters for hundreds of years? No, no, no. Ships don't exist. The ocean is all there is.

Just because they have maintained a fairly low and ambiguous profile in their survey doesn't mean they aren't visiting.

It is ridiculous to assume we could detect any form of intelligent life in our galaxy at our current level of technology. We do not even know if there is other life in our own solar system yet.

Just because we cannot detect does not mean they are hiding. Detecting anything over light years is a huge challenge.

"Intelligence, Hawking believes contrary to our human-centric existece, may not have any long-term survival value."

Hate to say it kids, but there might be more truth to this statement than any of us realize ..........., or want to admit!

Hehehe, May I bring to your attention an article called "The limits of knowledge"... as an "evolved" monkey how smart do we think we are ? At least to a civilization only a few hundred millions years old ?
Other than that, the premise of "exploiting OUR resources", when it seems planets are a dime a dozen, is woefully asinine. Anybody who is somebody, out there, is likely to laugh off OUR "resources". And the quotations from Hawking, do him injustice, make him sound like a pompous old fool...

We are also assuming that intelligent species develop at a constant rate. We're quite possibly just not interesting, or too dangerous. As Star Trek suggests, perhaps we are being watched while waiting for us to do something interesting.

That said, the development of complex intelligence on Earth was the result of billions of coincidences. We may very well be an incredibly rare commodity in the universe. So rare and precious that other civilisations wait until we've stopped shooting at each other to decide if we're safe enough to contact.

I agree with Hawking here, we should have to be wary of answering back, we need to better evolve.

Looking at the politicians one can argue that intelligence have yet to emerge on our planet. And this after 13.7 billion years of evolution. That says it all...

The Fermi paradox - "If there are technologically advanced extra-terrestrial entities, then why haven't we detected" them does not rest upon detection of electromagnetic transmissions alone. The rather rapid population of remote localities by self replicating Von Neumann probes being a more presssing issue.
One answer to the question can be made in terms of a kind of "cosmic censorship" by the non-biological cognitive entities of the kind which is on track to supersede humankind.

There is a serious problem with the most popular way of trying to establish the probability, the Drake equation . That is simply the inadequacy of reliable input. Even one incorrectly guessed input variable rendering the output meaningless.
We must always remember the IT mantra of GIGO : garbage in – garbage out.

However, with regard to the wider issue, a very good case can be made for the presumption that, whatever the time-scale, humankind will never encounter extra-terrestrial "intelligent" (I prefer the neologism "Imaginatory" ) life.

Simply because, should we manage to escape (or at least postpone) extinction, the next, non-biological, phase of "life" could well prohibit contacts of this kind between more primitive organisms such as we..

This kind of cosmic censorship provides one possible explanation for the Fermi paradox.

And it is consistent with the pattern of autonomous evolution of technology that is so evident today.
Very real evidence indicates the rather imminent implementation of the next, (non-biological) phase of the on-going evolutionary “life” process from what we at present call the Internet.It is effectively evolving by a process of self-assembly. You may have noticed that we are increasingly, in a sense, “enslaved” by our PCs, mobile phones, their apps and many other trappings of the increasingly cloudy net.

We are already largely dependent upon it for our commerce and industry and there is no turning back. What we perceive as a tool is well on its way to becoming an agent.

Consider this:

There are at present an estimated 2 Billion Internet users. There are an estimated 13 Billion neurons in the human brain. On this basis for approximation the Internet is even now only one order of magnitude below the human brain and its growth is exponential.
That is a simplification, of course. For example: Not all users have their own computer. So perhaps we could reduce that, say, tenfold. The number of switching units, transistors, if you wish, contained by all the computers connecting to the Internet and which are more analogous to individual neurons is many orders of magnitude greater than 2 Billion. Then again, this is compensated for to some extent by the fact that neurons do not appear to be binary switching devices but can adopt multiple states.

Without even crunching the numbers, we see that we must take seriously the possibility that even the present Internet may well be comparable to a human brain in processing power.
And, of course, the degree of interconnection and cross-linking of networks within networks is also growing rapidly.The culmination of this exponential growth corresponds to the event that transhumanists inappropriately call “The Singularity” but is more properly regarded as a phase transition of the on-going “life” process.
The emergence of a new and predominant cognitive entity that is a logical consequence of the evolutionary continuum that can be traced back at least as far as the formation of the chemical elements in stars.

The broad evolutionary model that supports this contention is outlined very informally in “The Goldilocks Effect: What Has Serendipity Ever Done For Us?”, a free download in e-book formats from the “Unusual Perspectives” website.

Interesting article, but the question isn't whether advanced ETs exist, but rather, whether at present, the governments, scientists--like Stephen Hawking--and people of our world want to know if they exist.

The link below suggests a simple experiment which costs nothing, and can be done now, which will show that ETIs exist, and have been interacting with our civilization for not just decades, but millenia:

The fact that this idea cannot even be discussed by the scientists of our world, like the folks at the Centre for the Study of Existential Risk, begs the question: Do you really believe that our civilization is more likely to survive and prosper in the coming pre-Singularity years and decades by ignoring any possibility, however slight, of learning of the experiences of other rapidly evolving technological civilizations?

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