I was at Readercon 19 last weekend and on a panel regarding the Fermi Paradox.
Genius scientist and SF writer Geoffrey Landis articulated the Fermi Paradox fairly neatly in his article (quoted below on Percolation Theory) : "If even a very small fraction of the hundred billion stars in the galaxy are home to technological civilizations which colonize over interstellar distances, the entire galaxy could be completely colonized in a few million years. The absence of such extraterrestrial civilizations visiting Earth is the Fermi paradox."
Fermi pointed out the problem in 1950. If you'll recall, we had just come out of a world war, had exploded bombs in Japan and were conceiving thermonuclear bombs (testing them in 1952). The idea of a nuclear end of civilization was a very real concern. It is my opinion that Fermi's question was just as much informed by that concern than a scientific query. In addition, we were also living in a period where we considered upcoming nuclear to be too cheap to meter. It was a time of optimism and terror.
The above articulation has components that need to be discussed: 1) the probability of technological civilizations arising and 2) the probability they would desire to colonise the rest of the galaxy and 3) longevity required for them to find us.
Some of this was looked at by the Drake Equation, which looks like this as shown in wikipedia:
N is the number of civilizations in our galaxy with which communication might be possible;
and
R* is the average rate of star formation in our galaxy
fp is the fraction of those stars that have planets
ne is the average number of planets that can potentially support life per star that has planets
fl is the fraction of the above that actually go on to develop life at some point
fi is the fraction of the above that actually go on to develop intelligent life
fc is the fraction of civilizations that develop a technology that releases detectable signs of their existence into space
L is the length of time such civilizations release detectable signals into space.
My own feeling is that fc is a complex variable:
ft: develops technology
fr: develops technology that can be recognizable
fd: detectibility of the detectible technology by us
Not to belabor what is already in the wikipedia, but the numbers in the article gave the number of civilizations as 10. I complexified the fc variable by taking their fc value of .01 and using it in above. fr I assigned a value of .5 to give a 50% chance of detectibility and fd a value of .01 as a possibility the signal could be detectible by us. Using these numbers I get a value of .05.
Paradox? What paradox?
What's most interesting about the Fermi Paradox is that it is viewed as a paradox at all. I had a huge argument with a friend over this. The problem is we have no evidence about a situation where we have no knowledge. All we know is we have no contact of any recognizable sort. Consequently, conclusions based on this absence are meaningless. My position was that all we know is we haven't been contacted in any way we can discern. Beyond that, We Don't Know.
But human being don't like those three words. So we speculate.
The links below are fun.
Here are my possible solutions. I hope they're as much fun.
Everything about these solutions presumes that non-relativistic systems are impossible. No FTL drive. No wormholes. We just have to send signals or travel for a really, really long time.
1) We are alone
2) Mechanisms for detection are phase delayed against evolution of technology that can be detected. E.g., comm. systems we would use for detection (radio waves) become finer and less broadcasty over the evolution of the technology: spectrum is a physical limit and the real estate is expensive. Therefore, there is only a brief period where signal detection of another civilization is possible.
3) Alien communication systems do not follow our paradigm of broadcasting low frequency photons in fairly regular patterns. Cephalopods are color based and have no non-visual color communication mechanism. (Some pheromones but not much.) Therefore, intelligent cephalopod comm systems might begin as visible light and never have a non-visual component-- transmitting sound was the first basis for radio. If they jumped to chemical lasers rather than radio and based their communication on that, we would never see it.
4) The probabilities are such that we just haven't had time enough to encounter them.
5) We only think it's possible to communicate/transit interstellar space because we haven't really tried it yet. In actually, it's much, much more expensive and difficult because of inescapable energy requirements. The physics underlying possible technology to do this has inescapable costs no civilization can withstand and survive.
6) There were lots of them a few thousand years ago. There was a gamma burst nearby and they are all dead. We were fortunate enough to have Jupiter in the way when it happened and that's why life on earth survived. But now we're all alone. Boo hoo.
7) There are inescapable cultural consequences for any species to attempt such an expensive undertaking. Species evolve from their heritage of what they were not because of what they wish to be. Therefore, any species that evolves to the point of creating the technology that makes it possible to communicate/transit across interstellar distances has within it qualities that make it impossible to do so. For example, look at how well we're doing at unifying the earth just to properly distribute food.
8) Phase delay of species evolution is against detection. Presuming a relativistic universe, it's unreasonable to expect to detect extra-galactic species. The distances are too great for that level of resolution. It may be unlikely to detect species beyond our spiral arm. Therefore, we must be discussing species that are at most intragalactic and at least intra-spiral. Could be the odds of intelligent life sprouting at all/within our time frame is against us. Or the species life span is against us locally. Or virtual transhumanism. Or build undetectible Dyson spheres. Or they lose interest.
9) What we perceive as universal constants that we use to communicate, such as binary systes, are not in fact universal enough to be used to communicate. We are detecting signal but it's just noise as far as we are concerned. Video patterns based on commercial scan rate. Split of tv signals between FM/AM, etc. (The WOW signal, for example.)
10) There are other civilizations but we're not invited for some reason. (Hm. Resembles my childhood.)
13) We're the first.
14) We're in a simplified simulation of real life. What we see isn't real. (from Nick Bostrom's argument.) The absence is itself evidence of the simulation.
-----------------------------------------------------------------------
Stuff on the Fermi Paradox
The Great Silence
An Astrophysical Explanation for the Great Silence
Why our search for Extra Terrestrial Intelligence has Failed
Fifty Ways to Find Your Alien Lover
When Aliens Don't Attack
Percolation Theory
There is no Fermi Paradox
Dyson Spheres
Fermi Paradox: Possible Solutions
Answering the Fermi Paradox
An Overview of the Fermi Paradox
Three Billion Earths
Refining the Drake Equation
Gamma Ray Bursts and the Fermi Paradox
Genius scientist and SF writer Geoffrey Landis articulated the Fermi Paradox fairly neatly in his article (quoted below on Percolation Theory) : "If even a very small fraction of the hundred billion stars in the galaxy are home to technological civilizations which colonize over interstellar distances, the entire galaxy could be completely colonized in a few million years. The absence of such extraterrestrial civilizations visiting Earth is the Fermi paradox."
Fermi pointed out the problem in 1950. If you'll recall, we had just come out of a world war, had exploded bombs in Japan and were conceiving thermonuclear bombs (testing them in 1952). The idea of a nuclear end of civilization was a very real concern. It is my opinion that Fermi's question was just as much informed by that concern than a scientific query. In addition, we were also living in a period where we considered upcoming nuclear to be too cheap to meter. It was a time of optimism and terror.
The above articulation has components that need to be discussed: 1) the probability of technological civilizations arising and 2) the probability they would desire to colonise the rest of the galaxy and 3) longevity required for them to find us.
Some of this was looked at by the Drake Equation, which looks like this as shown in wikipedia:
N is the number of civilizations in our galaxy with which communication might be possible;
and
R* is the average rate of star formation in our galaxy
fp is the fraction of those stars that have planets
ne is the average number of planets that can potentially support life per star that has planets
fl is the fraction of the above that actually go on to develop life at some point
fi is the fraction of the above that actually go on to develop intelligent life
fc is the fraction of civilizations that develop a technology that releases detectable signs of their existence into space
L is the length of time such civilizations release detectable signals into space.
My own feeling is that fc is a complex variable:
ft: develops technology
fr: develops technology that can be recognizable
fd: detectibility of the detectible technology by us
Not to belabor what is already in the wikipedia, but the numbers in the article gave the number of civilizations as 10. I complexified the fc variable by taking their fc value of .01 and using it in above. fr I assigned a value of .5 to give a 50% chance of detectibility and fd a value of .01 as a possibility the signal could be detectible by us. Using these numbers I get a value of .05.
Paradox? What paradox?
What's most interesting about the Fermi Paradox is that it is viewed as a paradox at all. I had a huge argument with a friend over this. The problem is we have no evidence about a situation where we have no knowledge. All we know is we have no contact of any recognizable sort. Consequently, conclusions based on this absence are meaningless. My position was that all we know is we haven't been contacted in any way we can discern. Beyond that, We Don't Know.
But human being don't like those three words. So we speculate.
The links below are fun.
Here are my possible solutions. I hope they're as much fun.
Everything about these solutions presumes that non-relativistic systems are impossible. No FTL drive. No wormholes. We just have to send signals or travel for a really, really long time.
1) We are alone
2) Mechanisms for detection are phase delayed against evolution of technology that can be detected. E.g., comm. systems we would use for detection (radio waves) become finer and less broadcasty over the evolution of the technology: spectrum is a physical limit and the real estate is expensive. Therefore, there is only a brief period where signal detection of another civilization is possible.
3) Alien communication systems do not follow our paradigm of broadcasting low frequency photons in fairly regular patterns. Cephalopods are color based and have no non-visual color communication mechanism. (Some pheromones but not much.) Therefore, intelligent cephalopod comm systems might begin as visible light and never have a non-visual component-- transmitting sound was the first basis for radio. If they jumped to chemical lasers rather than radio and based their communication on that, we would never see it.
4) The probabilities are such that we just haven't had time enough to encounter them.
5) We only think it's possible to communicate/transit interstellar space because we haven't really tried it yet. In actually, it's much, much more expensive and difficult because of inescapable energy requirements. The physics underlying possible technology to do this has inescapable costs no civilization can withstand and survive.
6) There were lots of them a few thousand years ago. There was a gamma burst nearby and they are all dead. We were fortunate enough to have Jupiter in the way when it happened and that's why life on earth survived. But now we're all alone. Boo hoo.
7) There are inescapable cultural consequences for any species to attempt such an expensive undertaking. Species evolve from their heritage of what they were not because of what they wish to be. Therefore, any species that evolves to the point of creating the technology that makes it possible to communicate/transit across interstellar distances has within it qualities that make it impossible to do so. For example, look at how well we're doing at unifying the earth just to properly distribute food.
8) Phase delay of species evolution is against detection. Presuming a relativistic universe, it's unreasonable to expect to detect extra-galactic species. The distances are too great for that level of resolution. It may be unlikely to detect species beyond our spiral arm. Therefore, we must be discussing species that are at most intragalactic and at least intra-spiral. Could be the odds of intelligent life sprouting at all/within our time frame is against us. Or the species life span is against us locally. Or virtual transhumanism. Or build undetectible Dyson spheres. Or they lose interest.
9) What we perceive as universal constants that we use to communicate, such as binary systes, are not in fact universal enough to be used to communicate. We are detecting signal but it's just noise as far as we are concerned. Video patterns based on commercial scan rate. Split of tv signals between FM/AM, etc. (The WOW signal, for example.)
10) There are other civilizations but we're not invited for some reason. (Hm. Resembles my childhood.)
13) We're the first.
14) We're in a simplified simulation of real life. What we see isn't real. (from Nick Bostrom's argument.) The absence is itself evidence of the simulation.
-----------------------------------------------------------------------
Stuff on the Fermi Paradox
The Great Silence
An Astrophysical Explanation for the Great Silence
Why our search for Extra Terrestrial Intelligence has Failed
Fifty Ways to Find Your Alien Lover
When Aliens Don't Attack
Percolation Theory
There is no Fermi Paradox
Dyson Spheres
Fermi Paradox: Possible Solutions
Answering the Fermi Paradox
An Overview of the Fermi Paradox
Three Billion Earths
Refining the Drake Equation
Gamma Ray Bursts and the Fermi Paradox
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