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New Paper Offers Additional Reasoning for Fermi's Paradox
KentuckyFC writes "If the universe is teeming with advanced civilizations capable of communicating over interstellar distances, then surely we ought to have seen them by now. That's the gist of a paradoxical line of reasoning put forward by the physicist Enrico Fermi in 1950. The so-called Fermi Paradox has haunted SETI researchers ever since. Not least because if the number of intelligent civilizations capable of communication in our galaxy is greater than 1, then we should eventually hear from them. Now one astrophysicist says this thinking fails to take into account the limit to how far a signal from ET can travel before it becomes too faint to hear. Factor that in and everything changes. Assuming the average communicating civilization has a lifetime of 1,000 years, ten times longer than Earth has been broadcasting, and has a signal horizon of 1,000 light-years, you need a minimum of over 300 communicating civilizations in the Milky Way to ensure that you'll see one of them. Any less than that and the chances are that they'll live out their days entirely ignorant of each other's existence. Paradox solved, right?"
We humans are God's only children. That's why there's no one else in the universe. And the universe was created 6k years ago. Duh! Scientists... what useful things have they ever done other than bring up heresy?
Assuming the average communicating civilization has a lifetime of 1,000 years...
Damn - We've got less time than I thought. Here I've been rooting for heat death. =(
He's getting rather old, but he's a good mouse.
No link to anything but Wikipedia and a blog?
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"Paradox solved, right?"
No. Some planets suitable for life have almost certainly existed in this galaxy for billions of years longer than the Earth. By now, one would expect there to have been civilisations that spread throughout the galaxy and therefore brought Earth within detection range of their signals...
Grr! Arg!
One of the thoughts that's crossed my mind as we further explore and understand utilization of quantum information is that if there is sentient beings "Out There" with some level of capability for space exploration is that it would seem that this would be a very likely way for them to maintain communication. Efforts such as SETI would then be attempting to discover background noise (I use the term "noise" here more as commentary on what most of what we communicate tends to be) of civilizations no more advanced than ourselves attempting only very nearby levels of communication.
Civilizations capable of greater levels of exploration would likely have developed means of utilizing communication along the lines of quantum information than our radio waves.
I thought it was because as they reach our level of civilisation, they built giant particle accelerators for research and turned their planets into black holes.
Maybe we are the first to achieve this capability. If life did create itself from a universe that created itself, ONE of the life forms which achieved this interstellar communication would have to be first. Why not us?
Easy solution: This is not a paradox to begin with.
...it means that civilizations that spread out and last longer than 1K years are exceedingly rare. Which would mean that our odds of achieving any meaningful interstellar travel are quite low. (We might make a space probe or two, but like how we got to the moon but haven't done anything with it, apparently nobody puts out space colonies.) There are other posible theories, though.
PHEM - party like it's 1997-2003!
This is hardly a new idea. It's so not new that I think I remember saying something similar about two years ago, and I'm not exactly an expert.
Analog signals degrade quickly, and digital signals are worse, in their way, because they don't tolerate degrading as well. Couple that with broadcast limitations imposed by local governments to keep signal strength down, and I can't see how our signal could be reliably detected more than a few light years away without a HUGE radio antenna array.
ad logicam Claiming a proposition is false because it was presented as the conclusion of a fallacious argument.
Did you read the summary? The point is that outside of our galaxy no intelligible signal is going to reach us. Therefore, the rest of the universe doesn't even enter into it.
You are using English. Please learn the difference between loose and lose; they're, there, and their; your and you're.
The scope of the Fermi Paradox deals with the length of time it would take an intelligent civilization to explore and colonize the galaxy, and given Fermi's estimates we should have observed spacecraft and/or probes. SETI's signal hunting doesn't even scratch the surface of the paradox.
The real answer is that they've been trying to communicate with us for years but RIAA, fearing they might play music for us has already had their ISPs throttle their messages into oblivion.
We humans are still a bunch of young, angsty teenagers. We desperately want to make the "first contact", crying and yelling and suffering from the depressive thought of loneliness.
Other galactic civilizations simply matured and stopped worrying about such pointless things. They make themselves busy with real business.
Grow up, humans.
Colorless green Cthulhu waits dreaming furiously.
What about new type of commutations that we have not invented yet? Its possible they are communicating all over the place but we can't hear them yet because we don't have the technology to hear them yet.
Summary says: "300 communicating civilizations in the Milky Way". The quote is: "300 communicating civilization in the galactic neighborhood". I interpret the latter to mean all solar systems within 1,000 light years. The former quote leads to the entire milky way, which has a diameter of 100,000 light years.
Suppose intelligent life was a super freakish accident, not a forgone conclusion. It took 4-billion years for it to develop on earth. I'll bet it might easily have never happened. And then, there was no reason why we had to develop a technology based culture. That, in itself, might have been a freakish cultural event.
So, maybe, we are pretty special after all.
Maybe there are advanced aliens looking for intelligent life.
If they found earth they'd keep right on looking.
As a species we're violent, irrational, deluded, greedy and self interested.
The occasional deviations from this norm in no way redeem us.
If I had a choice not to be involved with this disgusting species then I wouldn't either.
To my thinking the key is that we have such a narrow definition of life, since we are only aware of one kind - life on Earth. Perhaps there exist intelligent entities out there that are undetectable to us. Perhaps, they are so different that they are also looking for life but with an entirely different definition. So it's like ships passing in the night.
Unless it's been vastly misrepresented in mainstream presentation (like TFS), Fermi's Paradox sounds pretty ridiculously simplistic.
Other bad assumptions it makes, just off the top of my head:
1. Other intelligent civilizations want to engage communications with aliens who, for all they know, might try to blow them up or eat them.
2. Those civilizations are willing to spend resources to beam electromagnetic radiation out into space in the vague hope of someone noticing.
3. Other intelligent civilizations "capable" of "communication" will follow the same technological arc as us and develop electromagnetic communications rather than, say, quantum communications or something we haven't even thought of yet.
4. Those aliens will assume that WE (or some unknown aliens) will be listening carefully for extrasolar broadcasts.
5. Those aliens even have a concept of "communication" and aren't just some hive-mind that never needed to evolve social skills.
6. They didn't cut their Alien-SETI funding to pay for medical research or an Alien-Wall-Street bailout package or something. (I mean, what do you think the chances are that WE will broadcast for a thousand years?)
And so on.
Really, Fermi's Paradox sounds like me saying that if I sit on a lonely beach for a week and don't find a bottle with a message in it in proper English, there are no other intelligent beings in the world.
It's not like we're located close to Downtown Galaxy. We live out on the edge. There's probably some galactic equivalent of AT&T or Comcast that is telling everyone else "We'll be providing them with service 'soon'. So our monopoly is justified."
Either that or the installer showed up and we were too busy/unaware to answer the door. So they said they'd be back later.
Invalid Checksum. Retrying.
Imagine holding up a lit LED on top of Mt Everest. How far away do you think you'd be able to see that, even assuming clear viewing conditions.
Now back off and imagine how far away our sun would be easily distinguishable from every other star in the milky way. The closest neighboring star to us isn't even the brightest star in our sky.
Compared to our sun, all of our communications are on the level of that LED on Everest. That will give you an idea of the likelihood of spotting a signal from any distance, even without the background noise.
ad logicam Claiming a proposition is false because it was presented as the conclusion of a fallacious argument.
Hello (hello, hello)
Is there anybody in there?
Just nod if you can hear me
Is there anyone home?
It's possible that our technological advances will sufficiently alter our thinking to the point that the question of ET's will fade away to the point of being boring and moot. It sounds silly, but what if, for example, we discover that there is a God, and we get his telephone number the next morning? Speculative, but perhaps other civilizations simply transcend their curiosity at some point well before they travel beyond that horizon.
I think you mean to say "Poems? The lad fancies himself a poet!"
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>Maybe there really is no FTL, and other alien races are as leery of sending out giant
>seedships that they themselves can't ride in as we are, and are thus still hanging out in their home starsystem.
I'm sure I'm not alone in this, but I just had to say. If there really is no FTL, it is probably one of the most depressing aspects of existence.
A work that expires before its copyright never enters the public domain and thus enjoys eternal copyright protection.
"Oh, the universe is so big! Life must be everywhere" isn't an argument.
Sure it is. It's just not a good one.
Ultimately, the problem I have with the SETI project is that they're looking for signals that by nature will have to suffer lightyears of Free-Space Path Loss (In short: it's proportional to the square of the distance). Worse, since we assume such alien civilizations will be hanging out near a star for the most part (deep space is cold and lacking in resources), you have a gigantic open fusion reaction happening right behind your signal, raising the noise floor tremendously.
From a layman's perspective, I don't see how they could reasonably hope to see anything, especially if the aliens are like us and tend to direct their transmitted energy rather tightly to avoid wasting too much of it.
Lets say for instance that we can pick up a signal from Geosync Earth orbit using little more than a crappy whip antenna (See: Satellite radio) for a system with maybe 200dB gain in total. Now lets say we're looking for ET with a magical system that has a million dB worth of gain. The distance from the Earth to a Geo satellite is 26,200 miles. The distance from the Earth to Alpha Centauri is 2.57 Ã-- 10^13 miles. Just comparing the square of the distances (6.86 x 10^6 to 6.5536 Ã-- 10^26), you can see that a gain of 10^9 is just not going to cut it, not by a long shot.
It seems to me that the only way SETI could possibly work is if ET was narrow beaming an extremely powerful signal directly at Earth 24/7 for centuries, or if they were hanging out in orbit chatting away over CB radios in stealth spaceships. The most plausible reason why SETI has not found anything is that any signals that are out there are well below are detection threshold, and this is even before we begin to think about a civilization that moves beyond RF transmissions in favor of something more exotic (entangled photon radios?).
I read the internet for the articles.
So... you're saying that you're not Mr. Spock?
My blog. Good stuff (when I remember to update it). Read it.
Note the following:
1) Author is an MBA. The "Bouchet-Franklin Institute" is his private lab.
2) The place of publication, arXiv, while very useful in certain fields of physics, is not peer-reviewed. It's basically the same as posting this paper on your blog.
3) The arXivblog, not run by any people actually associated with arXiv (as far as I can tell) regularly posts completely inaccurate summaries.
4) The published paper is laughably simplistic. As others have pointed out, these are obvious considerations, and the paper is mostly argument and simple geometry. While it's nice to see some back-of-the-envelope calculations on a minimum civilization density for a given detection cutoff, that's exactly what this is -- back-of-the-envelope calculations.
"Space is big. Really big. You just won't believe how vastly, hugely, mind- bogglingly big it is. I mean, you may think it's a long way down the road to the chemist's, but that's just peanuts to space." -- Douglas Adams
I'll include some explanation. We've been dealing with science fantasy (I'll define that here as fiction that uses scientific sounding explanations of things for purposes of adding credibility to fantasy stories but which isn't exploring actual science) for years. The best of it points out somehow that it has some cheat (like the spice Melange or the Heart of Gold) that changes the rules of interstellar travel.
Because currently, without finding a way to cheat, those rules are ironclad and depressing, and basically mean that the nearest star is out of reach as far as we know, let alone zipping around the entire universe at will. How would you even navigate in something that vast let alone actually travel it?
It makes the question of extra terrestrial intelligence a question along the lines of a Medieval Churchman speculating on the number of angels that can dance on the head of a pin. A sort of interesting philisophical discussion but not much more than that.
For the record, I believe with metaphysical certainty that both extra terrestrial life and extra-terrestrial intelligence exist. I also believe with the same certainty that I'll never have any proof of that either way.
Fermi's paradox which boils down to "Where are they?" is living in fantasy-land. You want to know where they are? I'll tell you, "You can't get there from here."
"MIT betrayed all of its basic principles."
The calculation of 1000 years seems a bit too long. We can't figure out how to shorten it because we don't know how long we're going to be using broadcast signal based communication as opposed to some other more direct means.
My own contribution to the debate:
As technology advances the limited amount of available bandwidth becomes more valuable, while costs of utilizing it drop. The civilization migrates its bandwidth use from simple, extremely redundant, coding schemes (like AM and FM) to subtle, highly-efficient schemes that are virtually indistinguishable from thermal noise (like OFDM). They also use spacial multiplexing to re-use the same bandwidth over and over at various locations. This buries the few redundant parts of the signal (like the pilot subchannels used for synchronizing the receiver) in interfering noise.
The result is that, after a fairly short time, at a distance they are virtually indistinguishable from a hot black body - and lost in the sagans of other hot things in the galaxy.
Our first AM voice radio broadcast was at the end of 1906. 102 years later we're taking a big step in the transition to OFDM-or-CDMA-everywhere by shutting down "analog TV" and replacing it with OFDM-based digital. AM and FM are already using digital variants to squeeze more out of their spectrum. Any bets on how long until they switch, too?
Once the simple-modulation blowtorches are switched over the few remaining detectably-patterned signals will be soft voices crying in a wilderness of high-noise-floor. If we don't DELIBERATELY send some intended-to-be-noticed beacons we'll again be lost in the background - our own and the galaxy's.
A thousand years? In our case the detectability sphere looks to be only a tad over 100 years deep.
Don't blink!
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
Why are we soooo certain that we *want* to be found? I personally would prefer not to be a slave or a menu item to another race of beings. Honestly, what makes you think they will be peaceful or even tolerant of our existence if do find another civilization?
2 cents,
QueenB
HDGary secures my bank
Hell, man! Is there any intelligence down HERE!!
Jeesh! These scientist with all their assumptions and preconceptions. Last week, we were supposed to believe that because we're able to capture a few pixels of UV radiation from a distant star system, and it can be spun into a computer model of the planet's atmosphere. The whole thing is a bunch of naval gazing to keep a bunch of nerds a colleges employed. Get a job, guys.
Aah, change is good. -- Rafiki
Yeah, but it ain't easy. -- Simba
He did.
Creationist Textbook Stickers Declared Unconstitutional by CowboyNeal
The supposition is that we have the corner on intelligence. It's clear that Dolphins have a sophisticated and elaborate social construct that requires exacting communication to maintain. This appears from my vantage point to be evidence of intelligence. However there is a certain hubris to human intellect that assumes that if we can't understand it that it's not intelligent. Orangutans were intelligent enough to speak in sigh language before we taught it to them, however 50 years ago you would have been laughed at to suggest they would be capable of even their limited ability to hold a conversation.
The further we get from human forms of communication the more likely we are to disregard a species of having intelligence simply because we can't understand it.
It might be "noise", but it's still a distinct power band - not a black body distribution at all.
In the real world, exponential growth always hits limits. Why should technological progress be any different?
PHEM - party like it's 1997-2003!
Not anymore, they got comfortably numb, someone set the controls for the heart of the sun and now they've all gone to join the great gig in the sky.
It might be "noise", but it's still a distinct power band - not a black body distribution at all.
But it's a very broad band - and there are many of them. The amount of power needed depends on how far you want to go and what the background is that you need to surpass - and a major component of the background is thermal noise, pushing toward a thermal distribution of signals as well.
Yes the distribution is distinguishable - at least so far. But remember that you have to observe the signal in the presence of other backgrounds as well. (A narrow band filter like you can use to find an AM or FM signal just won't cut it.) How far away from the Earth can you make that distinction? And if scientists DO, would they attribute it to intelligent signal transmissions or look for some oddball physical process - in the emitter or the medium?
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
Except for RADAR. Maybe RADAR will be replaced too, but for now it's quite noticeable.
It's also highly directional and mostly in frequency bands that don't make it through the ionosphere all that well.
RADAR is already migrating from simple continuous streams of short high-energy pulses to broad chrips and other, more complex signals that give more information about the target (and have less power demand on the transmitter).
Aircraft location for air traffic control is migrating from RADAR to aircraft-mounted GPS beacons. (The RADAR will still be around for a while. But don't be surprised if it migrates to more subtle technology.)
Military RADAR has a big advantage if it looks like background noise to a target.
(Marine radar does NOT - it's really good if your little sailing yacht makes a big spot on the screen of the supertanker that could run you down - a spot indistinguishable from that of another supertanker. B-) But marine radar is low power.)
Short high-energy pulses chew up a lot of valuable communication spectrum. Moving to a lower-energy signal could make it more available for other uses, creating an incentive to migrate.
So don't be surprised if even RADAR eventually fades into the background.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
Send me $1,000. I guarantee you there is a 0.000000000001% chance that I will send you back $1,000,000. Of course, if you don't send me the money, the odds of me paying you are zero. So you should definitely send me the money.
...following the principles of Heisenburger's Uncertain Cat...
Our self regard makes us think of human like intelligence as the inevitable pinnacle of life. Perhaps we are wrong about that.
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He's just acknowledging the Gelgamek christians.
"I only speak the truth"
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And "New car, caviar, four star daydream, think I'll buy me a football team" is absolute rubbish, laddie! Get on with your commenting!
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Building a generation ship will easily be one of the most expensive and large-scale projects that our species has ever undertaken. A couple of willing colonists can't afford this alone. They need the entire population behind them.
If you want a vision of the future, imagine a youtube comments section scrolling - forever.
A planet that's right in the mid-range of liquid water. Venus is too hot for liquid water, Mars is too cold.
Then why water, why not another solvent? Because water and carbon compounds allow a much larger number of complex molecules than any other combination. All the experiments performed in laboratories, all the measurements done in astronomic observations have failed to reveal any sort of chemistry even remotely resembling water+carbon chemistry in complexity.
First of all, the entire reasoning is flawed.
It simply makes no sense, what so ever.
My case and point: Radio technology.
Now, I have used radio technology quite a bit. I have to say, I am not impressed so far.
Seems slow (Its a dog for wireless G, and well...can't get decent wireless N drivers for Linux because of greed, and patent problems in the US...etc, probably still is dog slow.)
Now, why would, a intergalactic civilization, use electro magnetic waves, to communicate, over a distance of hundreds of light years?
Sort of seems, well, impractical doesn't it? Yet, all of these learned people insist that is the ONLY POSSIBLY WAY TO DO IT. Sort of seems oxymoronic too. Somehow the intergalactic civilization can conquor huge distances, but can't even say hello to each other from one end of the empire to the other end?
It is just stupid no matter how you argue this point. Not only that, but I am going to rightly assume I think, that any civilization that comes into being, has to operate on at least some of the same principles as our civilization. You cannot coordinate advances in a galactic empire with such a system as using radio, it is too slow for the distances.
Remember the horse and buggy? That is what I compare radio too. Is there something better? Well, people during that day didn't think so. It was simply impossible to better than the horse and buggy.
Why? Well, because the leading scientists of the day said so.
Luckily the idiots all died out, eventually clearing the way for well, people who had a little bit more imagination. (That and their tenure was now up for grabs and people could now introduce new rigid ways of thinking.)
It just so happens some of those rigid, unoriginal ideas included the steam engine and well...greed.
What is the only way to send signals instantaneously without distance becoming a limiting factor in todays world?
Do we know of any such system today?
Well, yes we do. But, I won't mention it here, because it is at the very leading edges of computing and you will just have to look for yourselves. But it involves tapping unseen states of matter which exist outside time and space.
But, as I point out. Radio waves would be a totally useless system to use. Nobody seems to point that out, UNLESS of course we consider the other side of the Fermi Paradox.
Which basically is, since using electromagnetic signals is really stupid, and since a civilization of vast galactic means would not use them, and they are not here.
It is entirely possible they simply do not exist.
That is a scary thought.
I prefer the alternate view though. Why? Well, Earth cannot be that unique. I mean, I am willing to at least entertain the idea that in the entire galaxy, let alone the UNIVERSE, there was another planet, that came to pass with similair traits and that:
1) A very advanced civilization really does exist.
2) Like the horse and buggy, they over came all obstacles to thinking and discovered the secret of travel, outside space time, to any point and any place in the Universe.
Given the SIZE of the universe, here is where I believe the Fermi Paradox falls flat on its face:
If you could go anywhere in the Universe, why in the hell would you come to a planet like earth with retards on it?
I am serious. If you could travel the entire universe and utilize communications that had no problem with distance, in fact, distance and time was entirely NOT PART of the transportation system, how long would it take you to eventually come around to the earth?
I ask this because it would seem to me, once you discover such a system, keeping yourself confined to a single galaxy is dumb. (i.e. The Drake equation should really be recalibrated to the entire Universe, not just the galaxy.)
I mean, it is sort of like this: Once you invent the airplane. Would you SERIOUSLY restrict yourself to your little country? No, of course not, you would get in the pl
Got Geometrodynamics? Awe, too hard to figure out? Too bad.
Right after you post a list of your other winners.
And you might want to adjust your odds. You're not competitive with Mega Millions. The odds of winning your lottery are one in ten^14, or 100,000,000,000,000, for a cost of 1000 dollars.
Mega Millions pays out fifty times your million (currently, the number changes) dollars, costs one dollar to join, and has odds of one in 175,711,536.
Oh, another thing. What you're describing is a variation on a numbers racket. It's illegal for private citizens to do. Unless you're the Prime Minister of Norway or something, of course.
Weaselmancer
rediculous.
Unfortunately we don't have interstellar capability yet or any sign that there is a way around the speed of light. We're stuck in this solar system for the time being. Our radio signals will propagate no faster than c and our probes, once we make them, will be slower (at least for the foreseeable future.)
Round-trip talk time is two years per light-year.
Listening where we are can be done now. No wait for our signal to propagate to them, and their signal (if present) has already propagated to us.
Unfortunately, if they were also essentially spread-spectrum-only emitters by the time the stuff going by us now was sent, we're hosed. B-( Or at least we'll have to modify our filters to look for efficient-modulation signatures.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
I am not trying to single out this post, but half the thread seems to be assuming Fermi's paradox is about alien civilisations communicating with us over radio. This is 100% wrong. We are all actually talking about a paradox that was never postulated.
First, it has to be pointed out that the radio-wave idea has been discounted many times for a much more obvious reason. The period of time that any civilisation engages in communication by radio waves is likely to be a tiny fraction of a percentage of the total life of said civilisation. The idea of finding our alien friends through listening to radio waves was ridiculous when Carl Sagan was promoting it and remains so today.
Secondly, The Fermi Paradox is about alien civilisations *colonising* the Galaxy or "arriving here." It was originally phrased as the question "where are they?" (i.e. - they should be here by now given a finite universe and a certain amount of time.) As flawed as *that* idea also is, it's a completely different flawed idea than what most folks her are arguing about, which is the incredibly super-duper flawed idea of radio communication between advanced civilisations.