To me the most likely back of the napkin answer to the Fermi paradox is that aliens are elsewhere in time. The Milky Way galaxy is about 100,000 light years across but about 13.5 billion years old. So it’s like 135,000x deeper in the time direction than the distance direction.
We’re in the light cones of all the stars we can see, and as far as we know, we can’t get out of them. If a civilization ended even 100 years earlier than our equivalent “now” in their light cone, we wouldn’t have seen them. And if they became visible even 1 year later than our equivalent “now,” we would not have seen them yet.
We’re proceeding through time at 1 sec per sec and basically if we’re going to see an alien civilization at this point, I think the only way would be if one happens to achieve the necessary technology to be detected while we’re looking at it. If there were existing civilizations that were easy to see, we would have seen them already.
I think it’s far more likely we will confirm alien life first by indirect means, for example spectroscopically detecting free atmospheric oxygen on an exoplanet, or finding tiny fossils on Mars.
This is the L constant of the Drake equation. Probably the hardest to find a value for until we've actually discovered other intelligent life or remains of such. The confounding part of it is that we can only guess at things that may end a civilization so completely that it will never recover. Things like the so called Great Filters, natural extinctions like impact events or gamma ray bursts, or other more speculative things that prevent expansion. The tricky part is that our existence seems to fly in the face of such events so far, is that mere luck or do all forms of intelligent life have enough sense to navigate around these problems? The last and most paradox defining part of the problem is that even if the tiniest fraction of civilizations can evade these filters then they should eventually be everywhere in the galaxy. Assuming the Copernican principle that we are not at a special place in the universe or time then there should have already been ample opportunity for such civilizations to develop and hence Fermi's question "Where is everybody?".
> Great Filters, natural extinctions like impact events or gamma ray bursts
you know what really alarms me? these things are only chances on a very, very short-time scale. they are inevitable, yet no one seems alarmed when meteors come between us and the moon and we dont see it coming until hours beforehand.
sun bursts blowing out the electric grid, nuclear war, antiobotic resistance, crop and animal monoculture, climate change, natural resource depletion... taleb is right. we need an agent of chaos to make anti-fragility valuable. otherwise we learn the lesson the hard way. by dying.
> The tricky part is that our existence seems to fly in the face of such events so far.
We've only been here for a few minutes. We aren't really making any efforts to save the planet or colonize space. It's totally possible that we will wipe ourselves out before our TV and radio signals ever make it far enough to be detected by aliens, even if there are a ton of them out there.
There's the other end of a technology curve, when a civilization ceases use of an outdated piece of technology. In our case humanity is looking for radar because we're currently broadcasting it. Why would anyone continue using radar to communicate within a few years of quantum entangled data processing, capable instantly transmitting data instantaneously across vast distances? There might be a few living that rock star lifestyle of HAM radio operation and messenger pidgeons, but at that moment our civ would go narly completely dark to our sister civ's SETI program. All humanity's existence so far has been nothing but spark swallowed up by the darkness of time. Our use of radio a fart in the wind.
This theory is incredibly type-zero-civ-pocentric. A species capable of interstellar travel will have mastered technologies we can't even comprehend. By the time humanity is able to meaningfully reach across the stars, we'll have spread life across our entire solar system and everything we'd ever need. Unlimited energy from our sun, a lush and verdant Venus and Mars, mining colonies across the solar system producing vast quantities of any desirable element, not to mention an Earth whose biosphere is a shining jewel - perpetually locked-in at peak biodiversity.
Begs the question of what we would ever need from another civ, and furthermore what a similar civilization would ever want from a bunch of squatting troglodytes such as ourselves.
> Begs the question of what we would ever need from another civ, and furthermore what a similar civilization would ever want from a bunch of squatting troglodytes such as ourselves.
The need to fight loneliness and to find a kindred spirit?
That and the fact that civilizations probably only broadcast EM radiation out into the void for a short period of time before they start getting into energy efficiency and switch over to more efficient communication technologies.
Even broadcast emissions aren't detectable at long distances. If you parked an Arecibo-class telescope in orbit around Alpha Centauri the only signals you'd detect coming from Earth would be intentional directional transmissions from an Arecibo-class (or Goldstone class) radar.
Our television and radio broadcasts aren't detectable by an Arecibo-class telescope out much past Jupiter let alone outside the solar system. Even our high powered radar systems wouldn't be detectable out even half a light year from the solar system.
The only civilizations that can be detected with a SETI-like program would be ones intentionally transmitting directional signals. Even then out past a thousand light years even a multi-terawatt (EIRP) signal would be difficult to detect.
Like inverse square law is as unforgiving as the rocket equation. Anyone hand-waving either of those principals is not trying to have a meaningful discussion about interstellar communication or travel, they're just writing about science fiction.
You look at human civilization and that's exactly what's happened. We started off by broadcasting everything as loud as we could (which isn't very loud) and we've slowly transitioned to signals that are both quieter and don't really survive escaping the atmosphere.
I can't imagine an advanced species wouldn't follow a similar communications path. The only way we detect them is if they specifically target our spot in the sky with focused EM for a very long time, generations! After all, they have no clue when we would be in our evolutionary path.
And for that to happen, the species would have to first find us. Not just find us, find us while we are still listening.
And this is all with the assumption that FTL communication/observation is even a possibility (It likely isn't).
IMO, the simplest answer is that FTL communication and travel is impossible. Advanced civilizations across the galaxy have all come to the same conclusion.
We might be able to explore our own neighboring stars throughout generations but it's unlikely we'll be able to ever send a message to another civilization that will get there while they are listening (without spending huge amounts of power).
I have heard (can’t remember the source) that radar, especially military radar, continues to be a significant source of artificial-looking EM radiation leaving the Earth, even as radio and TV broadcasts have declined in power.
Short lived on those timescales, yes. But not necessarily short lived in terms of our perspective.
If we imagine that in the last 5 billion years, there have been a good solid 10,000 post-industrial civilizations, and each of those civilizations has lasted 10,000 years (in the post-industrial stage where they're detectable), then that implies that of the last 5,000,000,000 years, 100,000,000 of them have been host to a post-industrial civilization: a given year has on average 0.02 currently present civilizations in it.
Now, this hypothesis does probably imply that significantly interstellar civilizations are impossible, since it seems like if you've colonized say 20 stars, what disaster could possibly end your civilization?
(I think the most likely scenario is that we're the only civilization ever to have developed in the Milky Way. Everything else seems like it assumes a lot of additional stuff.)
Civilizations are only detectable for a short period of time. Once they understand physics, they no longer need radio waves or Dyson spheres or to travel through what we call spacetime.
And to add the evidence we do have; in the billions of years of life on earth, there has only been <200 years where any species had the will and the way to send deliberate communications into space. Observational evidence suggests that the time span of civilizations existing is vanishingly tiny compared to the vastness of time overall
Is it? I can move all sorts of distances, in different directions, at all sorts of rates. It's surely harder to go certain speeds than others, and in certain directions than others. But to move 1 year in time - I only have one speed and one direction to move.
What makes the dark forest hypothesis not so conving to me is that it has the presupposition that it is indeed possible to hide. An advanced civilization close to us that is surveying the sky for signs of life would have very likely identified earth as a very promissing candidate due to the presence of methane and oxygen in its atmosphere at the same time. So our star system would have long been under surveillance, before we had the chance to develop a technology that would reliable disguise our presence.
If such a technology is possible at all, only the very first advanced civilization had the ability to hide from all others. And only if they were able to develop it before any other civilization had been able to track them.
To some extent it might nevertheless be a reasonable strategy to keep as quiet as possible. But this strategy is less and less useful for the latecomers. If they were already tracked by a multitude of other advanced civilization they would hardly benefit from keeping quiet. Unless they (wrongly) think that they are an early advanced civilization.
However, if a couple of these civilizations start to openly seek contact to others, what can the hidden ones do? If a hidden civilization starts to fight one of these latecomers, it would need to leave its cover and make itself known to all other civilizations in its vicinity. If it follows the dark forst hypothesis, it could only do so, when it is sure that it is the only dangerous civilization in its forest.
This leaves me with the following alternatives:
- The forest is dark, because there is only one civilization out there that is very capable in hiding and has the ability to exterminate any latecomer efficiently and without traces.
- The forest appears dark, because it is thinly populated and we just have not looked enough for the others.
I agree with your logic but would add one more thing to it: There is no compelling reason to wait until a planet conclusively proves it has intelligence on it to nuke it into oblivion with a kinetic kill projectile. You don't really know how long it will take for an intelligent species that could compete with you to arise. Humans have moved pretty quickly on cosmological scales, there's no particular reason to believe we're moving at the max speed and a lot of reason to think otherwise. Compared to the amount of energy you can obtain over cosmological time periods, the expenditure of a kinetic kill projectile is nothing.
In fact, if you don't mind waiting a bit, it can be almost trivial. All you have to do is basically get a factory to the target system; it can use local resources to build a kinetic kill projectile efficiently out of a big, local hunks of rock and local hydrogen. Launching near-light-speed projectiles from lightyears away is the emergency "oh crap! They're smart already!" option. Killing a planet that only has dinosaurs on it is dead easy for these hypothetical intelligences and there's little reason to believe they wouldn't.
So I think the dark forest hypothesis falls down on the fact that not only has Earth been broadcasting loud and clear to the stars that it has life on it ever since the Great Oxygenation Catastrophe, which was somewhere around 2 to 2.5 billion years ago, the Dark Forest theory implies that any surrounding intelligence that arose and was capable of seeing Earth on that time frame should have hit it. That has not happened. And 2.5 billion years is actually significant even on cosmological time scales.
(Also, no, the dinosaur asteroid or other events were not kill projectiles. If an alien intelligence is going to kill-projectile Earth there's no compelling reason to just sort of inconvenience life... it's going to eliminate it. Hypothesizing a race capable of launching projectiles but being too stupid to realize it wouldn't do the job is too precise a level of incompetence to believe in. As they say, there's no kill like overkill.)
Fun science fiction premise... not a solution to the Fermi paradox.
You don’t destroy the system because you want to inhabit it yourself. This assumes that life is looking for similar habitats and that it’s not simpler to create an artificial planet anyway.
If I use humanity as a model, then we don't see other great apes as dangerous competitors. Rather we see them as interesting curiosities. We want them to stay alive. But it's hard to resist the desire to turn their habitats into something economically productive.
Colonizing other planets and making them into homes for aliens long before a native civilization has a chance to arise seems more plausible than just destroying them.
> There is no compelling reason to wait until a planet conclusively proves it has intelligence on it to nuke it into oblivion with a kinetic kill projectile.
Or send a technologically engineered molecule that can hijack single-cellular life to help establish your needed technology in the target solar system.
> An advanced civilization close to us that is surveying the sky for signs of life would have very likely identified earth as a very promissing candidate due to the presence of methane and oxygen in its atmosphere at the same time.
Signs of carbon-based life - who is to say all forms of life are carbon-based? The universe is vast, what are the odds of aliens being in our vicinity and time (light cone) stumbling upon our galaxy or star?
> Signs of carbon-based life - who is to say all forms of life are carbon-based?
There's a limited number of elements, and their abundance in the universe decreases rapidly beyond the first few. Carbon is by far the most advantageous for life due to its vast ability to form complex molecules. Silicon might be a distant second. If there is other life in the universe, and if there's nothing special about us, it might not all be carbon-based, but it's extremely likely that a large amount of it will be.
>However, if a couple of these civilizations start to openly seek contact to others, what can the hidden ones do?
Stay hidden or destroy anyone close enough to put you at risk along with themselves. This is a spoiler, but IIRC from the books the ultimate safety net was to make your solar system not only invisible... but impenetrable in either direction but essentially trapping yourself in a black hole... thus removing yourself from the equation and hopefully satiating anyone watching.
The time scales and distances involved meant that you weren't really perceived as a threat until you approached the ability to reach light speed, which made you stick out enough to be noticed in far corners of the universe. We broadcast radio, but it's not loud or far-reaching enough to be noticed by the far-out civilization destroying overlords. It was loud enough for a different nearby civilization to come destroy us in an attempt to save themselves from being destroyed along with us.
Of course, when applied in reality who the hell knows.
Am I missing something, or is this article very narrowly missing the most damning criticism of the Dark Forest hypothesis according to the article's own logic? The first paragraph of the “Criticism” section says:
> Overall, the Dark Forest Hypothesis has an internal logic and consistency that makes it an appealing (if somewhat somber) potential resolution to Fermi’s age-old question. Unfortunately, it also suffers from an inherent flaw that is capable of unraveling the whole thing. Like many other Fermi-related hypotheses, it only takes one exception to this rule to prove it wrong.
Given this, I thought it was going to follow on to point out that we are the exception to the rule, but instead it goes on to talk about malevolent exceptions. But, as the article mentioned earlier, we have made many active attempts to communicate our existence to other hypothetical civilisations, and we make no effort in obscuring our radio signals.
Is it possible that other civilisations follow the “Dark Forest” principle? Of course it is! But why would we happen to be the only civilisation that doesn't really worry about getting seen? The possibility that we are not alone and we are the only ones trying to communicate sounds even more fanciful and anthropocentric than any of the alternatives.
As other commenters have said, we can't take our own viewpoint as an example of what kinds of civilizations survive because our technological age is so young.
But IMO Dark Forest is bunk anyway, because it assumes that projecting power over interstellar distances is easier than defending yourself. That's not true within terrestrial history ... even though the arrival of colonists was massively disruptive to populations in (for example) the Americas, they couldn't have outright destroyed them. To survive, they had to trade and mingle with their neighbors, ultimately changing both cultures.
The sequels to The Three Body Problem kind of discuss this, and extend the dark forest idea to consider that any population that splits off from you is now a dark forest alien. I find that crazy xenophobic and ultimately an impractical black and white view of self vs other. On Earth, successful civilizations have been capable of trade and cultural exchange in addition to force.
>because it assumes that projecting power over interstellar distances is easier than defending yourself
This seems really obviously true to me. Accelerating a rock to relativistic speeds is pretty easy, defending against a rock potentially coming from anywhere in space traveling at relativistic speeds is extremely difficult.
> On Earth, successful civilizations have been capable of trade and cultural exchange in addition to force.
Forget about what monstrosities we have done to other human
civilizations throughout history. Instead, think about what we have done to animals. We have hunted many animals out of existence, or we have farmed them and made them basically the equivalent of the Matrix, sources of energy and food.
We are trying to eradicate mosquitoes for crying out loud, and entire species, without giving it a second thought. I will use insecticide to kill today entire colonies of ants without blinking.
All it takes is for one advanced alien civilisation to come across us and deem us the equivalent of their mosquitoes to eradicate us and take all the resources from the
Earth. That's the whole point of the Dark Forest theory. If there's an infinite number of civilisations out there, and one of them is so advanced that we are insects to them, why wouldn't they just exterminate us, or use us as food?
We are early in our "Space age". It's possible that inexperienced civilizations emit their position only to start hiding after realizing the dangers. Other possibility is that we are in a short period until we are wiped out because we broadcast our position.
All of this would drastically reduce number of visible civilizations at any time making the detection of civilizations much less likely.
Wouldn't the counterpoint be that those civilizations like us that do not obscure their location are quickly eradicated by others in the forest? So the forest also acts like a filter for those that are not careful enough.
I don't see that as a counterpoint, but more of a post hoc theory. How could the eradicators detect and destroy their victims before we detected any signal at all from the victims? And why haven't the eradicators come for us yet?
Of course, this could always be explained by the distances involved and the limitations of light speed, but that would make the Dark Forest hypothesis redundant as an explanation as to why we haven't yet detected any alien civilisation(s).
I don't see there being that big a technological leap between annihilating another civilization and starting a colony in another star system. If you're the type of civilization that would be interested in killing a competitor off you're probably the type that's going to colonize and fill the entire galaxy in a few million years. We evolved, so that hasn't happened, in a galaxy thirteen billion years old. I suspect we're alone.
1 exception doesn't disprove this rule. There could be any number of reasons for one or some civilisations to broadcast but not be destroyed:
* it takes time, we've only been broadcasting for 70 years or so. 70 light years isn't that far.
* we are far from dangerous listeners (we are right out on an arm in the milky way galaxy)
* all planets broadcast for a while at least (we did so without any serious consideration) and not all broadcasts end in annihilation. Up until just 40 years ago we seemed pretty likely to wipe ourselves out with war, even if an alien were planning our destruction, why not wait and see if we did it ourselves?
* Popular methods of destruction might not apply to our solar systems. If you rely on near by asteroids or free-floating planets to destroy civilisations and there happen to be none near sol, then we are safe to broadcast even if no one is safe to reply.
* if more than 1 alien actively destroys planets we might be lucky and have the aliens who detected us assume other aliens will destroy us. As long as they are happy to wait, we can broadcast in blissful ignorance believing we disproved the dark forest when we're actually just in the middle of a Mexican standoff...
* If a civilisation destroys other civilisations as soon as it detects them, you can use the abrupt destruction of civilisations to triangulate that civilisation. And destroy it. And that's a high priority since that way you find hidden civs AND ones which pose an immediate and serious threat to you. The best defence against this is to allow plenty of time between detecting and destroying a civilisation, especially a harmless unarmed (in the cosmic scale) one like ours. The lack of many close neighbours to us means a would be destroyer needs to wait even longer before striking us to maintain their annonimity.
Ironically this last point is the best argument against the dark forest: why destroy soft targets like earth when doing so reveals your existence? Why not wait, let someone else hit us and then hit them since they were a much bigger threat. So you'd expect a certain amount of noisy "prey" to be left as bait by one predator for another...
Also, I don't think we are broadcasting very much anymore. The move to digital broadcasts (lower power) and to Internet based comms/media (99% undetectable even from orbit) mean we're a lot less visible than we were previously.
The book responds to most of the "not there yet" concerns. The idea is that if there are 1,000 species aware of even primitive life on a particular planet, chances are at least one of them will be close enough for it to be worth the effort to destroy it. This is because technological development is exponential and you can't predict if/when a planet will produce dangerous technology equal or greater than your own. If you wait, you only increase the risk of being destroyed.
> If someone knocked on your door, quite unexpectedly, in the middle of the night, can I err on the idea that you would be quite panic-struck?
Quite likely, but only because the socially acceptable reasons to knock on someone's door in the middle of the night are usually something pretty bad. I wouldn't fear that they're attacking me. I would fear whatever they are waking me up to tell me about.
> If someone knocked on your door, quite unexpectedly, in the middle of the night, can I err on the idea that you would be quite panic-struck?
But if a stranger knocks on your door in the middle of the day you might just open up and say "no thanks, I don't want your pamphlet/vacuum/encyclopedia".
I mean, even if a stranger knocks, it seems weird to kill them assuming they're dangerous, even if we have "don't let a stranger in" etched in our collective consciousness.
> The possibility that we are not alone and we are the only ones trying to communicate sounds even more fanciful and anthropocentric than any of the alternatives.
Well, yes. But it could also make the (possibly) few blithe spirits who do want communicate be in general much further away, and thus much harder to communicate with.
I don’t think the Dark Forest principle asserts that all civilizations adhere to it. We might simply be the naive (or stupid) ones that get destroyed. That wouldn’t discredit the hypothesis.
We are also the only civilization we know of so we again may just be the dumb ones with a sample size of 1.
Ah... the "Dark Forest Theory". People really put way too much unnecessary time on it.
If the theory was true, then the first thing those "tree-body man" would reasonably do is to just destroy the solar system straight away with that super illegal (to the law of physics) raindrop probe. A civilization with the intention of discover and kill will definitely make their probes efficient kill devices, right? Why pay the expense of identify and kill the "Key actors" one by one when you can delete a entire system for cheap? Just turn the probe into a blackhole to kill the sun, it should be easy if the probe was really that dense.
A more direct attack is rooted in the theory itself: for the theory to be true, a state/condition called 猜疑连 (Chain Of Suspicion) must be created. The content of Chain Of Suspicion is simple:
- A civilization cannot determine if another civilization is evil
- A civilization cannot determine if other civilizations will view itself as evil
- A civilization cannot determine if another civilization will launch an attack against it
- A civilization cannot determine if itself is evil
- A civilization cannot determine if another civilization view themself as evil
- A civilization cannot determine if another civilization will treat itself in such way that been determined unevil
- ... ... (The article that I quoted from has this at the last line: https://wiki.mbalib.com/wiki/%E9%BB%91%E6%9A%97%E6%A3%AE%E6%9E%97%E6%B3%95%E5%88%99#.E5.8F.B6.E6.96.87.E6.B4.81.E6.8F.90.E5.87.BA.E7.9A.84.E2.80.9C.E5.9F.BA.E6.9C.AC.E5.85.AC.E7.90.86.E2.80.9D.E5.92.8C.E4.B8.A4.E5.A4.A7.E9.87.8D.E8.A6.81.E6.A6.82.E5.BF.B5)
Have you see the hole here? For a civilization that advanced, what are the chances that they're not equipped with also advanced social and science knowledge and skills? Heck, their advanced probe could probably even do all the observation and tests fully automatically and report the result back. The Chain Of Suspicion will never form to begin with because they CAN determine the facts if they really wants to. And then so the Dark Forest will never form too (at least not for the advanced side).
Now, let's talk about some serious thing. Because I've noticed some people uses the Dark Forest Theory to explain the relation between nations (yes, Earth nations). So it is really important to realize that the entire theory is nothing more than a plot device that Liu Cixin employed for his novel, among many other plots. Most of them are there to make the story more convenient, instead of more logical (as I have said, based on the theory, the logical thing to do is to wipe everything out at contact, how convenient that the probe "JuST cAnT" huh?).
So, if the theory inspired you do to something good, then nice, go ahead, have a good life, help people, communticate with others, try to understand others, have fun. However, if you believe the "Dark Forest Theory" is THE true governing rule of the universe, then you probably overthink it too much, stop it, it's not healthy. And guess what, the planet we're living on hosts multiple civilizations, you stick with us now no matter what.
I love that series -- just an incredible, imaginative, unique perspective -- but the dark forest hypothesis just doesn't make sense.
It's orders of magnitude of orders of magnitude less energy to communicate with (including obscuring your origin, if you want) than destroy a civilization. And communication has potential benefits (cooperation) that destruction does not.
Civilizations that communicated would very quickly and easily out-compete/out-advance civilizations that did not. "Malevolent" civilizations would inevitably run into more advanced cooperating civs sooner or later and be checked, either learning to cooperate themselves or lose.
Put another way, the assumptions used to build out the hypothesis, "Chains of Suspicion" and "Technological Explosion", don't make sense either. "Chains of Suspicion" assumes civilizations cannot communicate, yet the dark forest hypothesis assume civilizations can destroy each other. That's a contradiction. If you can physically interact, you can communicate (and as I pointed out before, with much, much less energy/resources than it takes to destroy). And "Technological Explosion", as written in the book, assume exponential technological growth could occur at any point, which seems to be nonsense to me. Any kind of exponential growth necessarily depends on a medium primed with the resources for that growth and stops when the resources are expended (which is never all that long, given the nature of exponential growth).
I cringed every time this idea was forced into the forefront of the books. They are such great and imaginative books, I don't mind at all that not all the ideas really pan out, but it was a little hard to stomach every time the plot turned on this weak idea.
I think dark forest is the best explanation so far.
If what you say is true, it should've been true for earlier human civilizations too.
Why didn't the Chinese and Japanese civilizations unite to conquer others?
Why didn't the Mongols unite with whoever else to conquer, instead of Genghis Khan doing it all with a bunch of Mongols in horses?
Human civilization is a dark forest that only changed with global trade. The communication challenge is language and culture. And civilizations have always been technologically distinct, with the more powerful one almost always conquering.
With interstellar communication and technological advance it would be orders of magnitude higher stakes.
Historically it's extremely rare that the conquerors killed everyone in the cities they conquered. Instead they enslaved some, or let them mostly live and just taxed them. Even with other species that regularly attack humans (tigers or even mosquitos), we have not exterminated them.
> "Chains of Suspicion" assumes civilizations cannot communicate, yet the dark forest hypothesis assume civilizations can destroy each other
> If you can physically interact, you can communicate
I think you misunderstood what they meant by "communicate". They don't mean "reach with a message", they mean "engage in back and forth communication with both sides understanding the conversation".
We're still struggling to talk to dolphins, but technically we could nuke them all to death if we ever got scared they were rising up.
But we're not struggling to talk to dolphins, they're struggling to materialize Shakespeare. We understand their structures and concerns more than they understand ours, and we observe them when they're still in the original soup.
ALl this to say: if they were rising up, we'd probably be able to create a bidirectional connection. We can only make sense "nuking them all to death", like you say in america to mean "defend our freedom and way of life", if we are able to communicate and are faced with a refusal to submit. The dolphin, so far, accept american hegemony - there's no purpose to nuking them.
So it is correct what you say, but here we're talking of civilizations. Civilizations worth nuking will always have a way to understand each others, otherwise there'd be no threat worth suppressing.
I also adore the series. It's become my favorite sci-fi I've read in years.
You're leaving out the time required to communicate. Yes, communication would require less energy, but time is a constant that even type 3 civilizations could be in short supply of.
The chain of suspicion calls this out explicitly, it's not that the civs cannot communicate, it's that due to the extreme lengths of time required for back-and-forth communications their societies are likely to significantly change during communications, leading to higher probability of the technological explosion.
What medium was primed for the technological explosion on Earth since the industrial revolution? I mean, I reckon we could point to an array of things that have seemed as though they would be a limit, but thus-far we've always found ways past that (see: peak oil). I'm not trying to indicate I think our trends _will_ go on forever, just that it seems possible they could.
Those books are pretty awful. They can't make up their mind whether they belong to sci-fi or fantasy. Sometimes they veer towards hard scifi but then make naive mistakes with current science. The characters are cardboard cutouts, very shallow, and make nonsensical decisions. The general atmosphere is depressing and ends in the complete failure of basically everything.
> It's orders of magnitude of orders of magnitude less energy to communicate with (including obscuring your origin, if you want) than destroy a civilization.
IIRC The Dark Forest addresses this directly - saying that wiping out a civilization must be cheap and casual. There's a chapter where an alien scout detects Earth, puts a dimensionality attack cartridge in a gun or something, launches it and goes on with their business.
I wonder if we're making too many assumptions about how civilizations would live and spread. I've always wondered why our species puts so much focus on planetary colonization instead of building smaller habitats. We seem to assume we'll terraform Mars, maybe build habitats on some of the Jovian moons, then jump to the next star. It seems more logical to me to take the ISS and iterate on it, building larger habitats and learning how to live in them.
There could be trillions of habitats out there and we'd never know it. From small low-orbit stations orbiting home planets to larger complexes orbiting their stars instead up to generation ships moving to the next star to mine for more resources or to build more ships due to population limits being hit. Once you've perfected the building of habitats that are large enough and are tailored to your species specific needs, why mess around with planets that can kill you in so many different ways?
Maybe the reason we don't see anyone is because we can't resolve even very large habitats at light-year distances and the reason we don't run into them is because we don't have anything they can't get somewhere that isn't already inhabited. Perhaps they avoid inhabited systems because of the dangers involved.
I agree, for an advanced species space habitats seem far superior to planets. A constant supply of free energy (solar), easy access to endless metal (asteroids), no earthquakes/tsunamis/volcanos/wildfires. If we're talking far-future, to me the Culture and their Orbitals represent the ideal utopian endpoint for humanity.
The O’Neillian movement is predicated on the answer to “is a planetary surface the best place for an expanding technological civilization” being no. Long run, this view will be most influential.
My favorite answer to Fermi's Paradox is a paper (which I do not have on hand) showing that it can be explained by the approximation error in doing a raw product of probabilities.
If, instead of doing a product of the probability of each event, you actually take the various distributions into account (nowadays you can easily test a wide variety of distributions with monte carlo methods) then, the probability of getting into contact with another life in the universe becomes vanishingly small.
My interpretation of that paper is that it is saying "We don't have hard enough bounds on the parameters of the Drake Equation, so one (or more) of the parameters could be much lower than expected". But without specifying which parameters are much lower than expected, the paper is just saying "our current understanding/uncertainty about the universe is consistent with someone solving the drake equation in some unknown way at a later point in the future". Which I don't think is actually a solution. The real question we are interested in is which parameters are lower than expected and why.
What would that be a "favorite" answer? It's just one of the hypotheses. Drake's equation and how exactly must it be applied has been fiercely discussed for decades.
Unless, of course, saying it's your "favorite" is your way of saying "I like to believe in this one hypothesis".
It removes the paradox without requiring additional hypotheses, just refining the math. That makes it the most convincing solution to the paradox for me.
> In other words, the finite nature of resources will ultimately pit one civilization against another as they all struggle to sustain their growth.
I'm not sure this constraint is so strict to force a strong competition for survival, given how vast the universe is. It seems to me this projecting our earth-bound mentality of limited resources to a whole different scale, where it may not really apply.
Precisely. IMHO any civilisation capable of interstellar travel (at any speed) has solved all necessary questions/problems of resource/energy acquisition and control and has no need to plunder the resources of others.
According to this theory, the resource consumers in the universe are just as vast as the universe itself. At the end of the series the final resource constraint they deal with is running out of physical matter in the universe. Once the civilizations depicted in the book are done mastering survival in this universe, they all turn their attention to surviving the death of the universe. Stability simply moves the survival goalposts, and “we could probably last a few billion years” (or rephrased, “we will probably perish in a few billion years”) becomes the new existential crisis to solve.
that is what I thought when I read the three-body problem.
If you can manipulate space-time at the levels exposed in the book you can trivially build orbitals that will host trillions of beings and live in a post-scarcity society for millennia, after which your society is likely to disappear waaay before you run out of space and resources.
Why or how would a post scarcity multi planetary or even multi stellar civilisation disappear? I agree that there is no need for plunder, but I don’t think highly advanced civilisations are in risk of extinction.
During star formation up to half of the matter can be rejected. During planetary formation a lot of fairly large bodies will be ejected, think moon size, along with a lot of smaller stuff too. Interstellar space probably has a lot more to offer than we generally think.
Given that most complex life is probably carbon based, and given the one planet with complex life we can observe, my guess is that most complex life runs into one of two paths:
1. You don't have enough easily accessible hydrocarbons in ground to build a civilization advanced enough to even get you into space.
2. You do have enough hydrocarbons which leads to inevitable overshoot, and accompanying collapse before you ever get close to figuring out interstellar travel. Exponential growth patterns lead you to either exhaust the carrying capacity of your planet, or you end up warming your planet too much and die off (or a little bit of both).
We're a pretty good case study between 1 and 2. Right now we're in a race to see if we can exhaust our hydrocarbons or overheat our planet first, there seems to be no realistic alternative (plenty of nice fantasy ones though).
If we had reached peak oil in the early 80s (or sooner) we would have likely avoided catastrophic climate change, but would have started a major population shift downwards towards 1 billion, where we would have likely stabilized but with no major technical progress (technological progress is largely a function of energy).
We didn't though, so now it seems like we are going to continue to increase the rate we combust hydrocarbons until we create an unlivable planet (at least for us). A few billionaires are making some cool toys, but we don't seem to be able to survive until we're anywhere near interstellar travel.
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We’re in the light cones of all the stars we can see, and as far as we know, we can’t get out of them. If a civilization ended even 100 years earlier than our equivalent “now” in their light cone, we wouldn’t have seen them. And if they became visible even 1 year later than our equivalent “now,” we would not have seen them yet.
We’re proceeding through time at 1 sec per sec and basically if we’re going to see an alien civilization at this point, I think the only way would be if one happens to achieve the necessary technology to be detected while we’re looking at it. If there were existing civilizations that were easy to see, we would have seen them already.
I think it’s far more likely we will confirm alien life first by indirect means, for example spectroscopically detecting free atmospheric oxygen on an exoplanet, or finding tiny fossils on Mars.
you know what really alarms me? these things are only chances on a very, very short-time scale. they are inevitable, yet no one seems alarmed when meteors come between us and the moon and we dont see it coming until hours beforehand.
sun bursts blowing out the electric grid, nuclear war, antiobotic resistance, crop and animal monoculture, climate change, natural resource depletion... taleb is right. we need an agent of chaos to make anti-fragility valuable. otherwise we learn the lesson the hard way. by dying.
We've only been here for a few minutes. We aren't really making any efforts to save the planet or colonize space. It's totally possible that we will wipe ourselves out before our TV and radio signals ever make it far enough to be detected by aliens, even if there are a ton of them out there.
This theory is incredibly type-zero-civ-pocentric. A species capable of interstellar travel will have mastered technologies we can't even comprehend. By the time humanity is able to meaningfully reach across the stars, we'll have spread life across our entire solar system and everything we'd ever need. Unlimited energy from our sun, a lush and verdant Venus and Mars, mining colonies across the solar system producing vast quantities of any desirable element, not to mention an Earth whose biosphere is a shining jewel - perpetually locked-in at peak biodiversity.
Begs the question of what we would ever need from another civ, and furthermore what a similar civilization would ever want from a bunch of squatting troglodytes such as ourselves.
The need to fight loneliness and to find a kindred spirit?
Our television and radio broadcasts aren't detectable by an Arecibo-class telescope out much past Jupiter let alone outside the solar system. Even our high powered radar systems wouldn't be detectable out even half a light year from the solar system.
The only civilizations that can be detected with a SETI-like program would be ones intentionally transmitting directional signals. Even then out past a thousand light years even a multi-terawatt (EIRP) signal would be difficult to detect.
Like inverse square law is as unforgiving as the rocket equation. Anyone hand-waving either of those principals is not trying to have a meaningful discussion about interstellar communication or travel, they're just writing about science fiction.
You look at human civilization and that's exactly what's happened. We started off by broadcasting everything as loud as we could (which isn't very loud) and we've slowly transitioned to signals that are both quieter and don't really survive escaping the atmosphere.
I can't imagine an advanced species wouldn't follow a similar communications path. The only way we detect them is if they specifically target our spot in the sky with focused EM for a very long time, generations! After all, they have no clue when we would be in our evolutionary path.
And for that to happen, the species would have to first find us. Not just find us, find us while we are still listening.
And this is all with the assumption that FTL communication/observation is even a possibility (It likely isn't).
IMO, the simplest answer is that FTL communication and travel is impossible. Advanced civilizations across the galaxy have all come to the same conclusion.
We might be able to explore our own neighboring stars throughout generations but it's unlikely we'll be able to ever send a message to another civilization that will get there while they are listening (without spending huge amounts of power).
If we imagine that in the last 5 billion years, there have been a good solid 10,000 post-industrial civilizations, and each of those civilizations has lasted 10,000 years (in the post-industrial stage where they're detectable), then that implies that of the last 5,000,000,000 years, 100,000,000 of them have been host to a post-industrial civilization: a given year has on average 0.02 currently present civilizations in it.
Now, this hypothesis does probably imply that significantly interstellar civilizations are impossible, since it seems like if you've colonized say 20 stars, what disaster could possibly end your civilization?
(I think the most likely scenario is that we're the only civilization ever to have developed in the Milky Way. Everything else seems like it assumes a lot of additional stuff.)
If such a technology is possible at all, only the very first advanced civilization had the ability to hide from all others. And only if they were able to develop it before any other civilization had been able to track them.
To some extent it might nevertheless be a reasonable strategy to keep as quiet as possible. But this strategy is less and less useful for the latecomers. If they were already tracked by a multitude of other advanced civilization they would hardly benefit from keeping quiet. Unless they (wrongly) think that they are an early advanced civilization.
However, if a couple of these civilizations start to openly seek contact to others, what can the hidden ones do? If a hidden civilization starts to fight one of these latecomers, it would need to leave its cover and make itself known to all other civilizations in its vicinity. If it follows the dark forst hypothesis, it could only do so, when it is sure that it is the only dangerous civilization in its forest.
This leaves me with the following alternatives:
- The forest is dark, because there is only one civilization out there that is very capable in hiding and has the ability to exterminate any latecomer efficiently and without traces.
- The forest appears dark, because it is thinly populated and we just have not looked enough for the others.
- We are the only ones in our cosmic vicinity.
In fact, if you don't mind waiting a bit, it can be almost trivial. All you have to do is basically get a factory to the target system; it can use local resources to build a kinetic kill projectile efficiently out of a big, local hunks of rock and local hydrogen. Launching near-light-speed projectiles from lightyears away is the emergency "oh crap! They're smart already!" option. Killing a planet that only has dinosaurs on it is dead easy for these hypothetical intelligences and there's little reason to believe they wouldn't.
So I think the dark forest hypothesis falls down on the fact that not only has Earth been broadcasting loud and clear to the stars that it has life on it ever since the Great Oxygenation Catastrophe, which was somewhere around 2 to 2.5 billion years ago, the Dark Forest theory implies that any surrounding intelligence that arose and was capable of seeing Earth on that time frame should have hit it. That has not happened. And 2.5 billion years is actually significant even on cosmological time scales.
(Also, no, the dinosaur asteroid or other events were not kill projectiles. If an alien intelligence is going to kill-projectile Earth there's no compelling reason to just sort of inconvenience life... it's going to eliminate it. Hypothesizing a race capable of launching projectiles but being too stupid to realize it wouldn't do the job is too precise a level of incompetence to believe in. As they say, there's no kill like overkill.)
Fun science fiction premise... not a solution to the Fermi paradox.
Colonizing other planets and making them into homes for aliens long before a native civilization has a chance to arise seems more plausible than just destroying them.
> There is no compelling reason to wait until a planet conclusively proves it has intelligence on it to nuke it into oblivion with a kinetic kill projectile.
Or send a technologically engineered molecule that can hijack single-cellular life to help establish your needed technology in the target solar system.
Signs of carbon-based life - who is to say all forms of life are carbon-based? The universe is vast, what are the odds of aliens being in our vicinity and time (light cone) stumbling upon our galaxy or star?
There's a limited number of elements, and their abundance in the universe decreases rapidly beyond the first few. Carbon is by far the most advantageous for life due to its vast ability to form complex molecules. Silicon might be a distant second. If there is other life in the universe, and if there's nothing special about us, it might not all be carbon-based, but it's extremely likely that a large amount of it will be.
Stay hidden or destroy anyone close enough to put you at risk along with themselves. This is a spoiler, but IIRC from the books the ultimate safety net was to make your solar system not only invisible... but impenetrable in either direction but essentially trapping yourself in a black hole... thus removing yourself from the equation and hopefully satiating anyone watching.
The time scales and distances involved meant that you weren't really perceived as a threat until you approached the ability to reach light speed, which made you stick out enough to be noticed in far corners of the universe. We broadcast radio, but it's not loud or far-reaching enough to be noticed by the far-out civilization destroying overlords. It was loud enough for a different nearby civilization to come destroy us in an attempt to save themselves from being destroyed along with us.
Of course, when applied in reality who the hell knows.
> Overall, the Dark Forest Hypothesis has an internal logic and consistency that makes it an appealing (if somewhat somber) potential resolution to Fermi’s age-old question. Unfortunately, it also suffers from an inherent flaw that is capable of unraveling the whole thing. Like many other Fermi-related hypotheses, it only takes one exception to this rule to prove it wrong.
Given this, I thought it was going to follow on to point out that we are the exception to the rule, but instead it goes on to talk about malevolent exceptions. But, as the article mentioned earlier, we have made many active attempts to communicate our existence to other hypothetical civilisations, and we make no effort in obscuring our radio signals.
Is it possible that other civilisations follow the “Dark Forest” principle? Of course it is! But why would we happen to be the only civilisation that doesn't really worry about getting seen? The possibility that we are not alone and we are the only ones trying to communicate sounds even more fanciful and anthropocentric than any of the alternatives.
But IMO Dark Forest is bunk anyway, because it assumes that projecting power over interstellar distances is easier than defending yourself. That's not true within terrestrial history ... even though the arrival of colonists was massively disruptive to populations in (for example) the Americas, they couldn't have outright destroyed them. To survive, they had to trade and mingle with their neighbors, ultimately changing both cultures.
The sequels to The Three Body Problem kind of discuss this, and extend the dark forest idea to consider that any population that splits off from you is now a dark forest alien. I find that crazy xenophobic and ultimately an impractical black and white view of self vs other. On Earth, successful civilizations have been capable of trade and cultural exchange in addition to force.
This seems really obviously true to me. Accelerating a rock to relativistic speeds is pretty easy, defending against a rock potentially coming from anywhere in space traveling at relativistic speeds is extremely difficult.
Forget about what monstrosities we have done to other human civilizations throughout history. Instead, think about what we have done to animals. We have hunted many animals out of existence, or we have farmed them and made them basically the equivalent of the Matrix, sources of energy and food.
We are trying to eradicate mosquitoes for crying out loud, and entire species, without giving it a second thought. I will use insecticide to kill today entire colonies of ants without blinking.
All it takes is for one advanced alien civilisation to come across us and deem us the equivalent of their mosquitoes to eradicate us and take all the resources from the Earth. That's the whole point of the Dark Forest theory. If there's an infinite number of civilisations out there, and one of them is so advanced that we are insects to them, why wouldn't they just exterminate us, or use us as food?
All of this would drastically reduce number of visible civilizations at any time making the detection of civilizations much less likely.
Of course, this could always be explained by the distances involved and the limitations of light speed, but that would make the Dark Forest hypothesis redundant as an explanation as to why we haven't yet detected any alien civilisation(s).
* it takes time, we've only been broadcasting for 70 years or so. 70 light years isn't that far.
* we are far from dangerous listeners (we are right out on an arm in the milky way galaxy)
* all planets broadcast for a while at least (we did so without any serious consideration) and not all broadcasts end in annihilation. Up until just 40 years ago we seemed pretty likely to wipe ourselves out with war, even if an alien were planning our destruction, why not wait and see if we did it ourselves?
* Popular methods of destruction might not apply to our solar systems. If you rely on near by asteroids or free-floating planets to destroy civilisations and there happen to be none near sol, then we are safe to broadcast even if no one is safe to reply.
* if more than 1 alien actively destroys planets we might be lucky and have the aliens who detected us assume other aliens will destroy us. As long as they are happy to wait, we can broadcast in blissful ignorance believing we disproved the dark forest when we're actually just in the middle of a Mexican standoff...
* If a civilisation destroys other civilisations as soon as it detects them, you can use the abrupt destruction of civilisations to triangulate that civilisation. And destroy it. And that's a high priority since that way you find hidden civs AND ones which pose an immediate and serious threat to you. The best defence against this is to allow plenty of time between detecting and destroying a civilisation, especially a harmless unarmed (in the cosmic scale) one like ours. The lack of many close neighbours to us means a would be destroyer needs to wait even longer before striking us to maintain their annonimity.
Ironically this last point is the best argument against the dark forest: why destroy soft targets like earth when doing so reveals your existence? Why not wait, let someone else hit us and then hit them since they were a much bigger threat. So you'd expect a certain amount of noisy "prey" to be left as bait by one predator for another...
Also, I don't think we are broadcasting very much anymore. The move to digital broadcasts (lower power) and to Internet based comms/media (99% undetectable even from orbit) mean we're a lot less visible than we were previously.
If someone knocked on your door, quite unexpectedly, in the middle of the night, can I err on the idea that you would be quite panic-struck?
But if humanity got a signal from another civilization tomorrow, do you think it is safe to err on folks being quite happy?
Quite likely, but only because the socially acceptable reasons to knock on someone's door in the middle of the night are usually something pretty bad. I wouldn't fear that they're attacking me. I would fear whatever they are waking me up to tell me about.
But if a stranger knocks on your door in the middle of the day you might just open up and say "no thanks, I don't want your pamphlet/vacuum/encyclopedia".
I mean, even if a stranger knocks, it seems weird to kill them assuming they're dangerous, even if we have "don't let a stranger in" etched in our collective consciousness.
Well, yes. But it could also make the (possibly) few blithe spirits who do want communicate be in general much further away, and thus much harder to communicate with.
We are also the only civilization we know of so we again may just be the dumb ones with a sample size of 1.
Attaining that technological level could be inherently linked with the ability to realize the dangers to begin with.
Spamming aliens with nude selfies, among other measures, which in retrospect may not have been a wise choice: https://en.wikipedia.org/wiki/Pioneer_plaque
If the theory was true, then the first thing those "tree-body man" would reasonably do is to just destroy the solar system straight away with that super illegal (to the law of physics) raindrop probe. A civilization with the intention of discover and kill will definitely make their probes efficient kill devices, right? Why pay the expense of identify and kill the "Key actors" one by one when you can delete a entire system for cheap? Just turn the probe into a blackhole to kill the sun, it should be easy if the probe was really that dense.
A more direct attack is rooted in the theory itself: for the theory to be true, a state/condition called 猜疑连 (Chain Of Suspicion) must be created. The content of Chain Of Suspicion is simple:
Have you see the hole here? For a civilization that advanced, what are the chances that they're not equipped with also advanced social and science knowledge and skills? Heck, their advanced probe could probably even do all the observation and tests fully automatically and report the result back. The Chain Of Suspicion will never form to begin with because they CAN determine the facts if they really wants to. And then so the Dark Forest will never form too (at least not for the advanced side).Now, let's talk about some serious thing. Because I've noticed some people uses the Dark Forest Theory to explain the relation between nations (yes, Earth nations). So it is really important to realize that the entire theory is nothing more than a plot device that Liu Cixin employed for his novel, among many other plots. Most of them are there to make the story more convenient, instead of more logical (as I have said, based on the theory, the logical thing to do is to wipe everything out at contact, how convenient that the probe "JuST cAnT" huh?).
So, if the theory inspired you do to something good, then nice, go ahead, have a good life, help people, communticate with others, try to understand others, have fun. However, if you believe the "Dark Forest Theory" is THE true governing rule of the universe, then you probably overthink it too much, stop it, it's not healthy. And guess what, the planet we're living on hosts multiple civilizations, you stick with us now no matter what.
It's orders of magnitude of orders of magnitude less energy to communicate with (including obscuring your origin, if you want) than destroy a civilization. And communication has potential benefits (cooperation) that destruction does not.
Civilizations that communicated would very quickly and easily out-compete/out-advance civilizations that did not. "Malevolent" civilizations would inevitably run into more advanced cooperating civs sooner or later and be checked, either learning to cooperate themselves or lose.
Put another way, the assumptions used to build out the hypothesis, "Chains of Suspicion" and "Technological Explosion", don't make sense either. "Chains of Suspicion" assumes civilizations cannot communicate, yet the dark forest hypothesis assume civilizations can destroy each other. That's a contradiction. If you can physically interact, you can communicate (and as I pointed out before, with much, much less energy/resources than it takes to destroy). And "Technological Explosion", as written in the book, assume exponential technological growth could occur at any point, which seems to be nonsense to me. Any kind of exponential growth necessarily depends on a medium primed with the resources for that growth and stops when the resources are expended (which is never all that long, given the nature of exponential growth).
I cringed every time this idea was forced into the forefront of the books. They are such great and imaginative books, I don't mind at all that not all the ideas really pan out, but it was a little hard to stomach every time the plot turned on this weak idea.
If what you say is true, it should've been true for earlier human civilizations too.
Why didn't the Chinese and Japanese civilizations unite to conquer others?
Why didn't the Mongols unite with whoever else to conquer, instead of Genghis Khan doing it all with a bunch of Mongols in horses?
Human civilization is a dark forest that only changed with global trade. The communication challenge is language and culture. And civilizations have always been technologically distinct, with the more powerful one almost always conquering.
With interstellar communication and technological advance it would be orders of magnitude higher stakes.
I think you misunderstood what they meant by "communicate". They don't mean "reach with a message", they mean "engage in back and forth communication with both sides understanding the conversation".
We're still struggling to talk to dolphins, but technically we could nuke them all to death if we ever got scared they were rising up.
ALl this to say: if they were rising up, we'd probably be able to create a bidirectional connection. We can only make sense "nuking them all to death", like you say in america to mean "defend our freedom and way of life", if we are able to communicate and are faced with a refusal to submit. The dolphin, so far, accept american hegemony - there's no purpose to nuking them.
So it is correct what you say, but here we're talking of civilizations. Civilizations worth nuking will always have a way to understand each others, otherwise there'd be no threat worth suppressing.
You're leaving out the time required to communicate. Yes, communication would require less energy, but time is a constant that even type 3 civilizations could be in short supply of.
The chain of suspicion calls this out explicitly, it's not that the civs cannot communicate, it's that due to the extreme lengths of time required for back-and-forth communications their societies are likely to significantly change during communications, leading to higher probability of the technological explosion.
What medium was primed for the technological explosion on Earth since the industrial revolution? I mean, I reckon we could point to an array of things that have seemed as though they would be a limit, but thus-far we've always found ways past that (see: peak oil). I'm not trying to indicate I think our trends _will_ go on forever, just that it seems possible they could.
Those books are pretty awful. They can't make up their mind whether they belong to sci-fi or fantasy. Sometimes they veer towards hard scifi but then make naive mistakes with current science. The characters are cardboard cutouts, very shallow, and make nonsensical decisions. The general atmosphere is depressing and ends in the complete failure of basically everything.
IIRC The Dark Forest addresses this directly - saying that wiping out a civilization must be cheap and casual. There's a chapter where an alien scout detects Earth, puts a dimensionality attack cartridge in a gun or something, launches it and goes on with their business.
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There could be trillions of habitats out there and we'd never know it. From small low-orbit stations orbiting home planets to larger complexes orbiting their stars instead up to generation ships moving to the next star to mine for more resources or to build more ships due to population limits being hit. Once you've perfected the building of habitats that are large enough and are tailored to your species specific needs, why mess around with planets that can kill you in so many different ways?
Maybe the reason we don't see anyone is because we can't resolve even very large habitats at light-year distances and the reason we don't run into them is because we don't have anything they can't get somewhere that isn't already inhabited. Perhaps they avoid inhabited systems because of the dangers involved.
If, instead of doing a product of the probability of each event, you actually take the various distributions into account (nowadays you can easily test a wide variety of distributions with monte carlo methods) then, the probability of getting into contact with another life in the universe becomes vanishingly small.
Unless, of course, saying it's your "favorite" is your way of saying "I like to believe in this one hypothesis".
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I'm not sure this constraint is so strict to force a strong competition for survival, given how vast the universe is. It seems to me this projecting our earth-bound mentality of limited resources to a whole different scale, where it may not really apply.
If you can manipulate space-time at the levels exposed in the book you can trivially build orbitals that will host trillions of beings and live in a post-scarcity society for millennia, after which your society is likely to disappear waaay before you run out of space and resources.
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1. You don't have enough easily accessible hydrocarbons in ground to build a civilization advanced enough to even get you into space.
2. You do have enough hydrocarbons which leads to inevitable overshoot, and accompanying collapse before you ever get close to figuring out interstellar travel. Exponential growth patterns lead you to either exhaust the carrying capacity of your planet, or you end up warming your planet too much and die off (or a little bit of both).
We're a pretty good case study between 1 and 2. Right now we're in a race to see if we can exhaust our hydrocarbons or overheat our planet first, there seems to be no realistic alternative (plenty of nice fantasy ones though).
If we had reached peak oil in the early 80s (or sooner) we would have likely avoided catastrophic climate change, but would have started a major population shift downwards towards 1 billion, where we would have likely stabilized but with no major technical progress (technological progress is largely a function of energy).
We didn't though, so now it seems like we are going to continue to increase the rate we combust hydrocarbons until we create an unlivable planet (at least for us). A few billionaires are making some cool toys, but we don't seem to be able to survive until we're anywhere near interstellar travel.