The Fermi Paradox Is Not Fermi's, and It Is Not a Paradox
blogs.scientificamerican.com
blogs.scientificamerican.com
"The universe is a dark forest. Every civilization is an armed hunter stalking through the trees like a ghost, gently pushing aside branches that block the path and trying to tread without sound. Even breathing is done with care. The hunter has to be careful, because everywhere in the forest are stealthy hunters like him. If he finds other life—another hunter, an angel or a demon, a delicate infant or a tottering old man, a fairy or a demigod—there’s only one thing he can do: open fire and eliminate them. In this forest, hell is other people. An eternal threat that any life that exposes its own existence will be swiftly wiped out. This is the picture of cosmic civilization. It’s the explanation for the Fermi Paradox."
It's true but there is a possibility that human radio activity does not last that long. We choose to transmit information using electromagnetic waves that propagates in every possible direction when there is no alternative, but it's a massive waste of energy and we may not continue to do so forever.
As a matter of fact, an increasing amount of communications travel through optic fibers, which are not observable from space. (And that's also why they're efficient)
If that's a correct prediction, we won't be pumping radio waves out of that rocks for more than a couple of decades. This is nothing compared to the age of the universe and may very well be missed, even if there's someone to observe.
And if we're wrong--if it is possible for a civilization to be capable of mounting an interstellar attack--they might not see themselves as a "fellow hunter." They might think nothing of harming us incidentally, like a kid burning ants with a magnifying glass.
The inverse-square law makes this a non-concern, doesn't it?
http://www.planetary.org/blogs/emily-lakdawalla/2012/3390.ht...
That is a huge over simplification. The fermi paradox doesn't really conclude. It is called a paradox because we need to solve the riddle that combined with the drake equation it is awfully quiet in our universe, why is that?
If you have 20 minutes: http://waitbutwhy.com/2014/05/fermi-paradox.html
This is probably one of the best long reads on the internet dealing with this question.
This makes no sense given that we exist, and the laws of physics show no indications that we are a special case, or that transforming the universe into intelligent matter is impossible. All it takes is one small group in one species to create the self-replicating probes that dismantle every natural grouping of matter to create more efficient arrangements to support more intelligence, and on a small timescale compared to the age of the universe entire galaxies are turned from wilderness to structure.
https://www.exratione.com/2015/05/the-cosmological-noocene/
"Per our present understanding of physics and intelligent economic activity, we will turn every part of that great span into our descendants if not diverted or stopped by some outside influence, stars and all. The cosmological noocene, an ocean of intelligence. That the natural universe remains present to be used by us indicates that something is awry, however, that some vital and important understanding is missing, and as a species we are still just making the first fumbling explorations of the bounds of the possible with regards to what it is that we don't know."
I think the problem of designing and building self replicating probes, capable of recreating themselves from asteroidal matter, is greatly underestimated. We currently have little to no idea how to design such a thing, and no real idea what the lower bound on the mass of such a thing might be.
The next problem is nterstellar travel. The difference un scale between traveling to the moon and travelling to a nearby star is about the same difference in scale between throwing a rock down a typical garden and launching astronauts to the moon. The Daudalus project did down good work on this and their very modest proble of just a few tons, doing a flyby of a nearby star, took a large to portion of the mass of Neptune to construct in terms of fuel. The resources available in a typical planetary system might not be up to the job.
I don't honk magic future technology hand waves these problems away. Any future technology will have to work with the same elements on the same periodic table we have now, manipulating the same physical forces we work with now. We can't wish magic unobtainable into existence and the limits of what is achievable with matter and energy are already pretty much computable.
So it really may well be that going sustainably interstellar might be impractical.
For a flyby: Daedalus mass = 5.0 * 10^7 kg (500 kg of scientific equipment)
With a slowdown to stay in the system: Daedalus mass = 10^10 kg
Mass of Neptune: 10^26 kg
So even for an extended stay, the mass of the Daedalus is no where close to a significant portion of Neptune.
I looked for equivalent mass objects, here is a few:
1.4 * 10^18 = all oceans on earth combined
10^12 kg = 1.4km diameter asteroid (Icarus)
3.5 * 10^10 kg = 0.5 x 0.3 x 0.2 dimension asteroid (Itokawa)
Estimates put the number of asteroids larger than 1km diameter in the belt between mars and Jupiter at 750,000
These are just straight mass conversions, no idea about the real content of fuel. If all those asteroids were straight fuel then you could launch upwards of a million Daedalus class ships that stay in the orbit of their target star.
The fallacy is that aliens must be using *technology that can be recognised as technology by early 21st century humans."
I suspect this is a low bar.
For all we know galaxies have already been transformed, and the curious science we're seeing - not least dark matter and/or dark energy - are the result.
Perhaps alien technology is non-material, and probes aren't any more necessary to aliens than head hunting is to us.
If you can manipulate spacetime and quantum phenomena directly, you're probably not going to spend a lot of time turning your star system or your galaxy into a showy megastructure.
It does seem unlikely that we are the first. But if it takes the average galaxy 20 billion years to evolve stable interstellar life, we may never hear from the others - even if there are millions of other civilizations in the universe.
The question here isn't the odds of interstellar life evolving. The question is how frequently interstellar life evolves in neighboring regions of space at similar times while displaying mutually recognizable signs of intelligence.
The "paradox" ultimately comes down to a lack of data. If the milky way evolves interplanetary civilizations every 5 billion years, it's clear the odds are stacked against ever meeting another living civilization... especially if FTL is impossible and transporting large masses at C is not viable.
The assumption that life naturally lead to computronium and self-replicating structures also seems unfounded.
One of my favourite responses involves cryptography: Given a sufficiently advanced civilisation, one might imagine that their ability to encrypt information is perfect, therefore any signal is indistinguishable from noise.
I started to read Solaris, but found the translation stilted and difficult, so gave up. I've just read that Lem himself didn't like the Rnglish translation! It's unlikely I'll be learning Polish this lifetime.
It's possible intelligent species inevitably overcome/loose the desire for infinite self replication.
It's clear other animals will breed to occupy all available habitats. But it seems humans uniquely are developing the idea of the preserve in which environments are intentionally left unoccupied. I have even heard a tiny amount of talk questioning the impact of even a Mars landing. If that question is already coming up centuries before interstellar travel, one wonders what attitudes will be prevalent then.
Just a century ago it was quite desirable to intentionally release new species of bird's into new continents purely for aesthetic reasons. Now such an attitude would be abhorrent.
I suppose if one could demonstrate that the desire to endlessly replicate across the universe is somehow beneficial to individuals currently living then I imagine their values will embrace it. If endless self replication is not beneficial to the exiting population then they will eventually reason their way clear of that instinct and that reasoning will be integrated into their ethical code.
So while I, like most people reading this, am very excited by space exploration, that attitude may not be a permanent cultural characteristic.
> ...technological civilization doesn’t last long enough for it to happen.”
Writer:
> Both York and Teller seemed to think Fermi was questioning the feasibility of interstellar travel—nobody thought he was questioning the possible existence of extraterrestrial civilizations
What happens when a technological civilization 'doesn't last long enough'? It stops existing.
But it did exist, which is clearly the point here.
>> Both York and Teller seemed to think Fermi was questioning the feasibility of interstellar travel—nobody thought he was questioning the possible existence of extraterrestrial civilizations
>What happens when a technological civilization 'doesn't last long enough'? It stops existing.
(your emphasis.)
Your observation that a civilization does not exist after it has ceased to exist does not "question the possible existence of extraterrestrial civilizations". To the contrary, unless we assume the author intended to state an empty tautology (which would be too pedantic an assumption to take seriously), then the statement I have just quoted is actually predicated on the assumption that it is possible for them to exist. So, when Fermi suggests that civilizations tend to fail before they colonize the galaxy, he is not questioning their possible existence.
Either this is worded wrong or illogical. If this is true, as it's worded now, then we humans either do not exist or are not intelligent, by its very definition. Both are ridiculous conclusions. The assumption is "because they would inevitably colonize the Galaxy by star travel". What if they're not advanced enough to do so yet? Does that make them not intelligent? If so, that would make us non-intelligent. Does that prove aliens don't exist? If so, then we humans are proven to not exist (which is ludicrous).
Finally the stupid conclusion: "since we don’t see any obvious signs of aliens here, searching for their signals is pointless." So as a corollary, other aliens searching for us would be pointless since we humans don't exist since there are no signs of us on other planets.
This is incredibly stupid. No wonder Fermi never wrote it. He would never write something this dumb.
This is also assuming that aliens will want to scout out the universe, and that probes are the best way for an advanced civilization to do so. We might be like someone from the past who comes to the present and determines that we don't have any long distance communication because they don't see any smoke signals.
But are we even dealing with a large sample size? Maybe there's "only" been several dozen large interstellar civilizations out there, and a few hundred small ones that never really got far beyond a handful of planets. Or maybe there were a couple of attempts, but they failed horribly. The problem with the "paradox" is that there seems to be a huge number of possible answers. It ends up being "how come this one scenario I'm thinking about hasn't happened."
P(probes) = 1 - (1 - P(a civ can launch a probe)) ^ N(civ)
If we don't see probes, and if we don't think P(can launch) is exactly zero, then N(civ) just has to be small.
EDIT: HN deleted my Fortran-style exponentiation.
In our Local Group of galaxies, however, we can confidently conclude that nobody has ever launched self-replicating interstellar probes. Which means nobody has ever evolved a technical civilization slightly more capable than our own.
Radio signals are ephemeral; probes are forever.
Perhaps the lack of probes means there is a fundamental flaw to the concept when applied to the actual, physical universe. Or that technologically advanced civilizations exist which aren't interested in sending self-replicating probes into interstellar space.
Not every civilization capable of trying may retain such technological capability forever, either. Even if attempting the trick is relatively rare in the life cycle of civilizations, those that can may not care to do so within the window of their capabilities. You could just as well argue that it's not possible for a civilization exactly as advanced as our own to prevent the launch of a deadly bioweapon which leads to their extinction. You could argue any number of logically sound things which may simply not shake out due to chance in the real universe. Maybe only a few such civilizations have actually arisen, and by pure chance, none of them have done it.
In another comment, I described the odds of these probes arising as
P(probes) = 1 - (1 - P(a civ can launch a probe)) ^ N(civ)
and unless P(can launch) is zero, not just really small, I think that we can conclude that N(civ) is not a very large number.
...and continuing to do so reliably for millions of years, somehow being able to efficiently fabricate arbitrary components of exceeding strength and complexity out of dust and ice, without any appreciable loss in quality of hardware or software, even in the radioactive environment of interstellar space. Just because a model is mathematically consistent doesn't mean it's practically feasible.
On the other hand, we are surrounded by earthly self replicating probes and we seem to be doing fine.
https://en.wikipedia.org/wiki/Rare_Earth_hypothesis
"the Rare Earth Hypothesis argues that the origin of life and the evolution of biological complexity such as sexually reproducing, multicellular organisms on Earth (and, subsequently, human intelligence) required an improbable combination of astrophysical and geological events and circumstances. The hypothesis argues that complex extraterrestrial life is a very improbable phenomenon and likely to be extremely rare."
The only question here is that even here on Earth, out of the tens of millions of species, only one is capable of creating advanced technology.
I am almost certain life exists elsewhere, but likely not intelligent.
I think it's far from a solved question how likely life is, given we have exactly one example of it arising.
And, even if the advancement is probable enough, be aware that the other civilizations don't have to have good intentions. Better avoiding signalling around.
Then the timeline of the life on Earth spans almost 4 billion years:
https://en.wikipedia.org/wiki/Timeline_of_the_evolutionary_h...
But we're "intelligent" enough for space travel only the last 50 years. But notice how the backward ideologies even got significantly stronger during the last 30 years and add to that that we've also probably spent a half of all oil in the last 100 years, which was probably produced during hundreds of millions of years, and that the awareness of that simple fact and its effects is also low.
There's nothing that guarantees that "it's always going to be better for us" no matter what we do.
"More than 99 percent of all species, amounting to over five billion species, that ever lived on Earth are estimated to be extinct." We initiated the last wave of extinctions.
Or as Taleb would write: "Consider the turkey before and after Thanksgiving." Every day the hypothesis "it's going to be better" is confirmed again and again. Until...
http://4.bp.blogspot.com/-qok3PSFR6NU/Ug4_QOjDUZI/AAAAAAAAA6...
"This naive projection of the future from the past can be projected from anything."
This is particularly clear when you think of it in terms of the Drake equation. We can devise reasonable estimates for parameters in terms of "number of habitable planets," but we know so little about how life works or how it starts that any later variable turns out to be complete guesswork. It's also sobering to learn that even our own ability to discover the history of life for which we have physical evidence turns out to be rather poor--being able to decipher Mayan script showed us that a fair amount of what we thought we knew about the Mayan civilization was just projection of archaeologists' opinions.
https://en.wikipedia.org/wiki/Andromeda%E2%80%93Milky_Way_co...
Far enough in the future, even if we survive, we won't see any other galaxy -- they will zoom out of our observable universe! The expansion of the Universe accelerates, according to our last estimates.
There would be no way to prove that another galaxy ever existed.
In even more distant future, eventually the supply of gas needed for star formation will be exhausted:
https://en.wikipedia.org/wiki/Future_of_an_expanding_univers...
In the exponentially distant future the Universe is going to get always more and more boring.
When future civilizations read "old" science texts it will be virtually impossible for them to not think of them as crackpot science or fairy tales. The idea of other galaxies ever having existed will have about as much verifiable scientific evidence as the tooth fairy
It's no wonder, at least not to my imagination why we haven't found any other life yet, or visa versa.
And in any case, if there is anyone out there, there should be some evidence. Scientists have looked in various ways for megastructures (e.g. Dyson Spheres) and have found no evidence for their existence, even in the oldest of galaxies.
The picture in my mind is quite bleak. The evidence seems to point to a very limited number of scenarios:
1. We are unique (in existence, in our technology, in our desire to expand, etc.) 2. We are first. 3. Civilizations destroy themselves before they can expand. 4. Civilizations do something else we don't yet understand that doesn't involve gathering more and more energy from surrounding space.
Just because humans breed with no point or purpose and even invent religion to insist on unmitigated population growth, doesn't mean that's a value shared with a more intelligent alien race.
If anything, there is proof that more educated humans breed far less than their counterparts. Extend that further and imagine a planet the size of earth with only a few million sentient life forms. They might not feel the need to leave, outside of general exploration, but even then they might just use probes.
A few points I'll make for fun:
1. Life on Earth propagates as much as possible. It is only external factors (mostly resources, but also predation and other factors) which keep populations in check. This is likely a shared trait of all (successful) life in the universe. This doesn't preclude the possibility of a species moving beyond this trait* but it does suggest that either the trait fails at some point prior to stellar engineering or interstellar colonization or that all advanced civilizations move beyond it.
2. Even if spreading throughout the universe is not a species' goal, whatever their goals are will require energy. It is likely those goals will require greater and greater energies as our own goals have and will continue to do for the foreseeable future. The only way I see around this problem is novel physics which seem impossible in our current understanding of the universe.
3. At some point every species must leave their host star or perish. (However, if they find themselves around a red dwarf, they will have quite a bit of time - and will not have to have moved since the beginning of the universe. So it may be we are freaks because we are around a shorter-lived orange star.)
But this is speculation at best. I'd rather speculate that they all created their own pocket universes that are ideally suited to their species and left the rest of us behind. :)
*Although I would suggest that natural selection is an unlikely candidate for the development of such a trait. In my opinion, this would require directly modification of whatever passes for DNA in the species. Even enforced population controls would probably not be enough to contain a species.
To achieve frequent non-robotic travel beyond a solar system, a species would have to first master unlimited "free" energy (ie. fusion). This seems to be an extreme non-trivial problem. Even a civilization tens of thousands of years ahead of us may not have mastered it on a portable scale, limiting their travel and making "home" far more comfortable.
And again, with unlimited energy, they still might not even feel the need to leave their solar system except for basic exploration, they might be xenophobic.
If the spark of the dna for virtually all life on earth maybe came from somewhere else, injected into our potent primordial soup, perhaps it happened when the galaxy, even the universe was closer together so it didn't have to travel so far. But now the few other "cousins" of life we have in the galaxy/universe may be too far away simply from the expansion of space itself, not just big-bang momentum.
It can't be a paradox if you know you can change the question.
At this point, scientists are looking for someone who would want to talk to us. (We are very unlikely to intercept anything not intended for us.) Anyone who wanted to talk to a fledgeling civilization is probably smart enough to know to use radio waves.
It's like complaining that a letter from America to Europe would travel for many months in 1495. There were still incentives for Europeans to go to America.
If the speed of light is the ultimate speed limit, technological civilizations may just have to accept it and work within that limit. Just because a method of communication is slow doesn't mean it's not worth using.
They probably die.
It's traveling to other star systems what is hard.
OTOH we live in a relatively sparsely populated neck of galactic woods; thicker clusters of stars exist with much shorter interstellar distances. Conditions there are usually deadly for us, though.
Yes. So? I reiterate my previous argument.