For a while I’ve been trying to figure out how to resolve the Fermi Paradox. For those of you who don’t know, the Paradox is, given what we know about life, the universe and everything, there should be a significant number of alien civilizations in our galaxy. The reasoning here boils down to the Drake equation (a Fermi problem), which lets us get a ballpark estimate of how many extraterrestrials are out there. From wikipedia:
N = R* × fp × ne × fl × fi × fc × L
where:
N = the number of civilizations in our galaxy with which communication might be possible;
and
R* = the average rate of star formation per year in our galaxy
fp = the fraction of those stars that have planets
ne = the average number of planets that can potentially support life per star that has planets
fl = the fraction of the above that actually go on to develop life at some point
fi = the fraction of the above that actually go on to develop intelligent life
fc = the fraction of civilizations that develop a technology that releases detectable signs of their existence into space
L = the length of time such civilizations release detectable signals into space
One easy way to deal with the Fermi Paradox is to plug in low numbers for fl, fi, fc and L. It’s pretty easy for me to see how it could be rare for life to arise, but I find it quite implausible that there are very many living planets out there that won’t at some point create intelligences capable of making radios. Most of this is moot, however, because the Drake equation deals only with present civilizations, not past ones. It’s my understanding that any civilization with a level of technological power greater than or equal to where we’ll be in a century or so would be able to easily make Von Neumann probes.
A Von Neumann probe is essentially a self-replicating spaceship capable of autonomously exploring the galaxy. On each probe is a beacon that broadcasts its findings as it explores and when it finds a new system it establishes a factory that makes more probes. Each factory also has a beacon, so the probes know to avoid previously-explored systems. Because of the self-replication factor a single Von Neumann probe would likely be able to blanket the entire galaxy with beacons in less than ten million years. Initially this seems like a long time, but considering the galaxy has been around for over 12 billion years it’s a curiosity to me that SETI has been operating for so long without any trace.
So how do I resolve the Fermi Paradox, especially considering self-replicating artifacts? Just recently I found a hypothesis which seems reasonable, and I’ll lay it out in the form of axioms and conclusions. When I talk about “power” below I mean ability to reach assorted goals. Intelligence, resources, and knowledge are all forms of power. When I talk about “the singularity” I mean an intelligence explosion that leads to a civilization being controlled by artificial intelligence (which may or may not be acting in accordance with the desires of its makers.)
Axiom: Contact with a less intelligent alien has no significant power benifit post-singularity.
Axiom: Contact with a more intelligent alien has a mild power benefit if they are benevolent.
Axiom: Contact with a more intelligent alien is incredibly dangerous if they are hostile.
Axiom: A society capable of inter-stellar spaceflight is almost certainly going to be post-singularity.
Axiom: A constructed intelligence will always destroy an alien that might possibly interfere with its goals if said alien is not an asset and protection or existence of said agent is not explicitly a goal.
Axiom: Evolved intelligences will typically not state explicit preservation goals for aliens when building their superintelligence. (Many will likely not even code in preservation goals for their own species.)
Therefore: Alien civilizations will either be major existential threats or of no real value.
Therefore: A rational intelligence will avoid attracting attention from aliens if not actively hiding from them.
Therefore: A civilization will have only a tiny window between when they develop radios and when they are either wiped out or hidden away by advanced AI.
Therefore: There may be plenty of intelligent life out there, but it’s likely hanging around star systems hidden by Dyson spheres.
Okay, so it’s not quite predicate calculus but it was the easiest way for me to organize my thoughts. If you find errors with my logic or disagree with an axiom please leave a comment. ^_^
5 Comments
Whitley Strieber claims to have had a decade’s worth of contact with a race of aliens that have been intelligent for billions of years but in a state of stasis where they cannot evolve. The highest value of their civilization is novelty, and Strieber explains that this is why they limit their interaction with us, since contact between primitive and advanced civilizations (even on Earth) ends with the advanced civilization eradicating the native one(s). An interesting idea, whatever its origin.
Any inquiry into the motivations of advanced (immortal) civilizations and entities will have to consider more issues than a simple threat/benefit profile. Greg Egan has a lot to say about this in his SF books, which can get pretty overwhelming.
Suppose that the emergence of a conscious human race causes a observational impact on quantum events so that it results in a frame-dragging effect in a “many worlds” universe, such that our emergence changes the constraints of reality.
If, for example, previous conscious civilizations discovered how to travel backward in time and change the past, they would continue to do this (in all likelihood) until their alterations to the timeline resulted in editing the universe into a state where time travel into the past (and probably into the future) was impossible. The emergence of a new consciousness reopening such possibilities would create uncertainty for all of the other conscious entities riding on the same spacetime vector. See what I mean?
Hey there,
Well, there are many problems, but the biggest one is that no one at NASA has been able to keep radio contact with probes beyond Neptune. The New Horizons Pluto probe should get there in about ten years, so we’ll see if they can keep contact with it.
While I appreciate what Sagan said about aliens, I’m not sure that they would want to contact the humans until the humans can show a little more, well, humanity. I also seriously, seriously doubt in our ability to communicate with such, should they be able to contact us (since we can’t contact them.)
There are also some questions that you miss. Does intelligent life require a stable large moon in orbit? Since life has evolved and been wiped out several times, one must take into consideration that, since life getting almost totally wiped out has happened several times here. That would slow or speed up the evolution of intelligence on another planet. Does that life have any interest in the stars or can they see the stars at all? For many many years no one could see the stars on this planet because of cloud cover and continual rain.
The distances are damning and I’m not sure a post-singularity species would find humans interesting enough to interact with them. I could see aliens coming to Sol’s system to look at Saturn.
But it’s fun to speculate, of course. It is better for us to do so because it helps humans with themselves. Watching Avatar is about ourselves and a good opportunity for some hard questions.
hugs
me
A discussion with the Doctor lead to some interesting stuff.
The only way to signal that it could be seen from far away would be to mess with Sol. Astronomers usually look for changes in the stellar field.
We could look at variable stars. FM or AM patterns would certainly indicate something, possibly intelligent.
Why are variable stars different according to where they are in the sky? Could it be deliberate? Rather than look at thousands of star maps, why not put down navigation beacons around the galaxy. Quasars might be the equivalent of GPS.
Cool thoughts. It’s fun to think about….
First, the technical bits:
@Anne/Mom:
I’m pretty sure the Voyager spacecraft is well beyond Neptune and still in radio contact with the Earth.
I’m also not familiar with the theory that life has re-emerged several times on earth. It was my understanding that stromatolite fossils put the origin of life sometime within the first billion years of Earth’s existence, and the consensus is that it’s been continuous since then. I’m also not aware of any disasters that brought life close to ending completely, but I’m probably just ignorant there.
In my post I tried to mention that low values of fl and fi in the Drake equation don’t really impact the Fermi paradox because of the tenacity of self-replicating space-probes. This means that whether a big moon is required for life, or intelligent life isn’t really an issue.
@Mike:
I have absolutely no idea what multiverse frame-dragging would look like, much less how it applies to the conversation. The stuff you’re going into seems to me to be fringe enough that you’ll have to elaborate much more before I’ll be able to relate it to the topic. (I’m not sure how to interpret your time-travel example either. It seems to me that to “alter the timeline” is paradoxical.)
More generally:
@Mike:
I’m afraid I haven’t read any Strieber or Egan, so forgive my ignorance here. Why would a civilization value novelty over everything else? And more importantly, why would such a society be interested in other planets if they could just make their own aliens using random seeds? What keeps them from “evolving”? And do you mean “evolve” in the biological sense or in the sense of progress?
With regard to whether there are “more issues than a simple threat/benefit profile” at work for modeling alien motivations, I assume that civilizations/beings capable of spaceflight are rational. By “rational” I mean their actions are always made with the intention of furthering their goals.
To the best of my knowledge, humans don’t actually have an intrinsic goal to visit other worlds, but they do have a goal to explore and perhaps even conquer. This seems likely to be the case for any evolved intelligence, as well. Now, in a post-singularity, if your goal is to explore, why go off-world? Why not just simulate other planets and get lost in endless games?
One could argue that people like the “real thing”, but I’d bet a super-intelligent machine built to protect people would almost certainly talk such an individual out of generating such a huge existential risk.
Now, I admit that there is a possibility that an artificial intelligence could be given a core goal that involved contacting aliens, but out of all the possible goals this one seems very small. Even a superintelligence that emerged from a SETI-like program wouldn’t want to contact aliens (only locate and monitor them).
If there is no core goal of extra-planetary contact and the being is rational, I fail to see how a comparison of potential power benefit with risk is an oversimplification.
@Anne/Mom:
I’m not really sure why aliens would want to look at Saturn or contact humans only after a specific ethical threshold. Both of these ideas seem like the result of anthropomorphic bias.
I may be off in thinking that we could see alien beacons, but I guess I just assume that an advanced civilization interested in contacting others could propagate Von Neumann probes and we’d be able to see one sitting at the edge of the solar system if this were the case.
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THANK YOU BOTH FOR THE THOUGHT OUT REPLIES! ^_^
Well, I thought visiting Saturn and not Earth would be because Saturn is kind of interesting, although we haven’t seen that many planets in other systems for comparison.
If we’re still in contact with Voyager, I did not know. I’m ashamed to wonder if it’s past the Oort Cloud. If we’re still in contact, I stand corrected. Dr. Coyote might argue it, though. Some of this was a result of conversation, not just my opinion alone.
I think just about anything can fly (not literally!) with the alien question. But I’d want humans to be a little more evolved before dealing with aliens. But that’s just me. I like meeting people on equal ground, not as a fan, not as fans, so to speak.
As far as “almost” die outs, the Cambrian extinction and the asteroid that wiped out most of the dinosaurs come to mind. It would only take something really trivial to wipe out humans. There is some speculation that a large moon is necessary to stabilize the climate. But maybe a world could evolve independent of stability? As I said, with speculation of alien life, all is possible. I still think communication would be more involved than most people would ever imagine, even with math as a common ground.
THANK YOU FOR THE INTERESTING POSTS!