But I would also say there is no reason to assume we would *not *be able to communicate. There’s a big difference between trying to communicate with a sentient, technological species and the species that humans have up to now tried to communicate with.
Yes, that’s probably a fair point.
I’ve noticed the same confusion with characterization of the Fine Tuning Problem. On the one hand, we have the religious misconstruing “problem” to imply that cosmology has run into something that can only be explained by divine planning; then in reaction to that, people making the equally misleading claim that there is no problem. But it’s somewhat similar to Fermi - there is an open “problem” in the sense that apparent fine tuning requires an explanation; and there are possible (naturalistic) resolutions, but we aren’t certain which is correct.
There is actually a lot of reason to think that there may be great difficulty in communication from a neuroscience perspective. Much of the higher cognitive functionality of the human brain is evolved around verbal communication augmented by visual cues and other non-verbal “body language”. An alien lifeform will have evolved from a completely different basis from the core affective responses all the way up to whatever method they use for conceptual communication (assuming that they even communicate abstract concepts in any analogue to spoken and written communication), and indeed, they may have very fundamental differences in how they perceive and model the world from their sensory perception to their notions of mathematics.
An alien intellect that doesn’t look at the world in terms of discrete, countable objects, for instance, isn’t going to have any comprehension of basic arithmetic, so the common assumption that we can at least have a basis for communication based upon integer values and fundamental constants may not hold, and if we don’t share other sensory or social constructs–say, a species that does not have any concept for “hunger” because they have evolved in a nutrient-rich environment, or does not have familial groupings or rear children–it may be very difficult to establish any basis for communication in fundamental ways.
Stranger
All correct. And you’re close to the conclusion I wanted you to reach.
First, you might note that while ~2.5k years is a long time to reach the nearest star, it’s not so long as to be impossible. Second, you might note that human lifespans are a technical problem and one that alien species might have found a solution to, and we can reasonably expect that humans will find a solution to this one. Maybe not in time for anyone alive today, but it is not reasonable to expect over the next millennia for every adult human engineer, scientist, or research funder to just resign and go to their grave without trying to make progress on the problem first.
Radiation vulnerability is another technical problem and also the starship’s crew didn’t need to move, being most likely computational circuitry but *possibly *being mammalian brain tissue in some sort of support system you could use a heck of a lot less shielding.
Basically, if a voyage like this is even possible at all, and alien species with the technical capability to make it have existed for millions of years, and some members of that species have different desires than others, and once a subgroup of that species makes the first voyage, their descendants would be more likely to have that desire…
Basically if the rules of our universe work anything like we think, we should be up to our necks in aliens.
So either :
a. Like Stranger says, the rules are different
b. There aren’t alien species with advanced technical capabilities anywhere near Sol.
Here’s one alternative they have considered (see below). The mass requirement is nowhere near planet sized and quite doable.
Also, I am curious if your calculations assume lifting the mass off earth or starting from space? There is a big difference there. We could get fuel from Titan (which has more hydrocarbon fuel than there is on earth) and more easily boost it into orbit and then go from there.
I would think that given the impossibly huge requirements of fuel, the logistics of space travel, and the inordinate amount of time the journey would take (and whether humankind’s existence on the planet would even last that long), a much simpler project would be establishing some kind of a FaceTime like communication technique with other intelligent creatures in the universe. A much more sensible investment of resources I would think.
Agreed: I also think that a desire to close a gap that people have traditionally put a god in, makes some people rush to say there is no gap, or it’s been explained.
There’s no need to block “god of the gaps”; it’s fallacious. OTOH, admitting “we don’t know…yet” is one of the most important things for us to acknowledge, and often a necessary step to discovery.
Well yes “much” not “most”. There are a lot of functions that I can say “much” of the human brain has evolved around.
This is exactly the reasoning that I am alluding to, and that I think is flawed.
Imagine we have two alien species.
One evolved deep in the oceans of a world covered in water. Much of its brain is dedicated to processing a kind of sonar.
The other evolved on a fiery hellscape of a planet, and it’s main sense detects differences in Sulphur dioxide concentration.
But these two species master interstellar travel and encounter each other in space.
On the one hand we might say what hope is there of these two species communicating? Their worlds, their realities are 180 degrees separated, they have nothing in common etc etc
But on the other hand, one thing we know is these two species mastered interstellar travel. And interstellar space is neither an ocean nor is it on fire. Neither sonar nor SO2 detection is useful here.
So both species must have some kind of generalized intelligence that allows them to solve problems wholly unlike those encountered in their natural environments. And they are masters of this; they’ve solved countless thousands of individual problems like this to end up in space.
So now, consider detecting and decoding an alien language to be a problem / task. Why would this task be intractable?
I would argue it would be among the easier problems that either species has needed to solve: it’s structured data, and it’s a problem that will likely actively try to help you solve it. If only every problem the universe served up was like that.
(FTR: I am aware no-one said anything about two interstellar species in this thread, but I am arguing against a general statement that alien species may not be able to communicate.)
The Fermi Paradox is really only puzzling if you assume that some things that we have absolutely no examples of and have never succeeded at doing are commonplace and easy. Interstellar travel is a lot harder than shown in science fiction, and in general requires extreme energy investment or extreme amounts of time. None of the planets that we’ve found are anywhere near ‘earthlike’ in the sense that you could live on them for an hour without being in a controlled environment; when astronomers say ‘earthlike’ you have to remember that these are people that consider what makes up most of the air you breath as ‘metals’. Yes, people spread out from Africa, and animals spread to various places on the earth - but the Earth is an extremely close destination (none of that travel required an interstellar drive) that is extremely hospitible to life. There’s no economic incentive for intelligent life to spread arbitrarily wide, and harvesting materials at light-year distances generally doesn’t make much sense.
Basically, “The Fermi Paradox” is an overly dramatic name for “we aren’t sure exactly which of the myriad reasons we can think of why we don’t see aliens everywhere apply” and not the “we can’t think of any way that aliens would not spread anywhere” that most people think when hearing it.
Arguments based on ‘since the future is very long and there might be lots of people in it, and what I want to do might save some lives under this set of assumptions, therefore do what I want to do now’ aren’t actually convincing. In principle, it’s pretty easy to either refute the argument or make it apply to whatever alternate path there is (‘if I save 100,000 poor people today with famine relief, that’s saving their billions of descendants!’) . In practice, this kind of argument isn’t even noticed; it’s not like a congressman is going to lose an election because he didn’t deal with an entirely abstract problem that won’t hurt until billions of years in the future.
Not exactly. It just assumes that, in the ~13.5 billion years our galaxy has existed, at least one civilization has invented interstellar travel and chosen to start expanding into the galaxy.
And don’t forget the powerful effect of evolutionary forces. The members of that species with “wanderlust”, that are also ok with creating descendants of themselves that are not dependent on fragile biology (so they can survive the radiation and thousands of year low power waits of interstellar travel), would make descendants (or clones) of themselves with similar traits.
You would expect over a universe wide selection process to encounter aliens with the kind of traits that cause them to fill up the entire universe with more instances of themselves.
…And our peasant looks at the Moon:
Do you know me? Surely not.
Then how have I offended you
that you’ve gone a million miles just to plant your flag on my dreams?
Listen, America:
I, the poet Ben Abdel Jalil Noureddine, make this petition—
I know I don’t have much say in the matter—
but just a word, America, from one man to another:
How I read my soul by the light of her face
that she’s not what she used to be, or
will never again so brightly shine, or
rise singing that way through the dark morning,
brushing the stars from her hair.
So you spared no expense, seducer,
but for both our sakes, my enemy, send her back to me!
And this I plead in the name of my soul
in the name of my people
our revolution in the name of the Moon.
(a Moroccan poet in Hideous Kinky)
You are assuming that language (in some fashion, whether spoken, written, or in another form) is communication; in fact, language is merely a tool for the high level communication of abstract ideas and relies upon some kind of commonality in how the world is perceived and constructed in the mind of the entities communicating. Humans are able to communicate with one another because we have not only common experiences (emotions, physical needs, social structures) but because we also have an essentially common sensory experience of the world and an internal construction of it.
Communicating with an alien intelligence that does not share the fundamental affective (emotional) responses that underlie our cognitive experience may be very limiting, even moreso if we are at different stages of intellectual evolution. We can imagine trying to communicate with pre-modern humans from, say, a hundred thousand years ago, and even though we have a common cognitive structure for communication, there is very little experience that as modern humans in a technological society we could relay to them in terms they would understand, and even in the converse most modern humans would have little notion of the subsistence existence.
That both species “have some kind of generalized intelligence that allows them to solve problems wholly unlike those encountered in their natural environments,” is no guarantee that they will actually have any fundamental basis for communicating abstract ideas or even a similar enough cognitive construction of the world to share abstractions. Add to that that two wholly unrelated species may perceive the world on completely different timescales–we see the world as events on the order of fractions of a second, whereas an alien intelligence might see it in terms of hours, or years as gestalts–and the difficulties of having any kind of commonality for communication of anything beyond the most trivial and facile ideas may be essentially impossible.
Stranger
It took about 3 billion years for complex life to appear on Earth AFTER simple life had already appeared. We have no idea if this is a giant outlier or not. It could be that it generally takes 8 billion years before that happens, which could make us one of the first civilizations.
In addition, of the millions of species that have evolved, only one ever reached the point of being able to harness technology. And if it weren’t for a ‘lucky’ asteroid strike many millions of years ago, we might still have dinosaurs roaming the Earth and mammals could have been an evolutionary side show.
The fact is, we still know next to nothing about the universe. We’re pretty good at understanding fundamental laws that apply to us, but we’ve never traveled in interstellar space, never accelerated a large mass to fractions of light speed, have not directly imaged the surfaces of any planets outside of our solar system, etc. There could be a million unknown unknowns out there that prevented some exponential takeover of the universe by the first expansionary civilization to come along.
In fact, I think you could almost expect there to be some kind of limiting factor, because we see limiting factors to geometric expansion everywhere we look in nature. The fundamental flaw of malthusianism was to assume that exponential expansions go on forever, when in the real world they always seem to run into limits, and this also seems necessary for the world and the universe to be stable.
But forgetting that, let’s just focus on the numbers for a second. To start with, let’s exclude all the other galaxies, because we would have no chance to detect a civilization in another galaxy in the first place unless it was capable of engineering on a galactic scale.
So, in our own galaxy there are estimates of as many as 40 billion earth-like planets around sun-like stars in their habitable zones. That may sound like a lot, but it really isn’t. Now we can start whittling that down. How many of those suns are located in highly dense areas where radiation and gravitational disturbances might prevent a mult-billion year stability required for complex life to form? How many of those stars and planets have been inundated by nearby Supernovae, or were in the path of a gamma ray burst in the last four billion years, or had their systems distorted by gravitational waves from a nearby black hole or white dwarf merger, or were affected by other galactic catastrophes we don’t yet understand?
Of the ones that weren’t, how many were created in regions low in metals or other elements that would have prevented sophisticated life from evolving? How many of those systems had other problems like ‘hot Jupiters’ migrating out and completely distorting the orbits of the other planets?
The answers to all these questions, and probably a thousand more we don’t even know we need to ask, could be the answer to the Fermi paradox. For example, let’s start by saying that maybe our place in the galaxy is somewhat special - being two thirds of the way from the center of the galaxy in a spiral arm may in fact be the ‘sweet spot’ for life, and all the stuff near the center, where the majority of stars are, is just too hostile for life to survive for billions of years. Now suddenly the candidate list for planets that could evolve technological life could be in the low billions. Cut that in half because we probably wouldn’t be able to detect civilizations in any way on the other side of the galaxy.
Once you are down in the billions or hundreds of millions, you’re now in the realm where pure chance could be a factor. Maybe we’re just the lucky ones.
For the Fermi paradox to be a real paradox, you pretty much need to assume FTL travel, self-replicating probes, and a universe that will allow self-replication until everything has been taken over. If there’s no FTL, it’s entirely possible that we think we are ‘alone’ merely because we have had the bad luck of growing up in a sparse region where everyone else is too far away from us to detect - yet.
As for interstellar travel, we still don’t know the density of ‘stuff’ in the interstellar medium. The fact that a fairly large rock randomly came very close to us recently (Oumouamoua) suggests that there is actually a LOT of debris between the stars (by a ‘lot’ I mean enough that you might encounter on average at least a particle or two on any straight line between two stars). If that’s the case, then it may not be possible to travel at even a reasonable fraction of the speed of light, because at relativistic speeds even a grain of sand would release a nuclear bomb’s worth of energy if it hit you. What happens to the equations for speed of expansion if 99 out of 100 replicating probes is lost through impacts on the way to each star?
I think most people believe that if there were civilizations out there, we should have detected them by now. But that’s just not true. For example, if another civilization had antennas as large as ours and had them pointed right at us, and we broadcast omnidirectionally from our most powerful broadcast amplifiers, they couldn’t hear us at all unless they were within just a few dozen light years. So we shouldn’t expect to hear the equivalent of radio or TV broadcasts from anyone unless they were essentialy right next door - say, within the closest 100 stars or so. And that seems highly unlikely.
Also, the Earth is in the process of going ‘dark’, as we are moving to fiber, laser, and microwave communications instead of giant omnidirectional broadcasts. We can expect other civilizations to do the same, as it’s much more efficient to use directed energy than just omnidirectional broadcasting.
But here’s the happy news: We are going to get some serious answers to these questions very soon. Our next generation of telescopes coming online now and over the next two decades are going to dramatically change astronomy and our understanding of the universe. We are going to be able to directly image some exoplanets, and we’re going to be able to start sniffing the atmospheres of many, looking for telltale signs of life and/or industry.
So right now, our ability to detect life elsewhere has relied on scattered radio observations on just a few of billions of possible frequencies. Soon, we’ll be looking directly at planets and their atmospheres, which gives us a chance to spot even primitive life or primitive civilization if they pollute.
If we still have not spotted any signs of life 20 years from now after our 30 meter telescopes and James Webb and other scopes scour the nearest planets looking for bio-signatures, this discussion will be much more interesting.
That’s a fair distinction to make.
I would agree that there needs to be some kind of commonality before abstract meaning can be conferred.
However, I would add that it is not proportionate: to understand 70% of what you are trying to communicate, my experiences do not need to be 70% the same as yours. And of course two alien species trying to communicate already do have a number of things in common: the universe and physics, deep space which they are both inhabiting if encountering each other there, the fact that they both can cooperate within their species to develop complex technology etc.
I would disagree with at least half of this.
Humans from technological societies interact and decode languages from fairly primitive societies right now; because, like I say, you just need a little commonality to crack open the door, and from there, since language is structured, the rest gradually unravels. We can also translate ancient languages where enough written records exist (if we were able to interact with those ancient people, it would be much easier).
If we were to go into pre-historic times we may find there are concepts in our world we could never explain to adults even given years…it’s just too alien for them.
But I would never claim a less technological species would be able to understand everything about a more technological species could say.
Arguably, the most important realization that humans have come to is that our senses are not capable of perceiving every phenomenon: there are things that are too fast or slow for us to perceive, too small to see directly or just invisible. Pair that with the proposition that such phenomena can nonetheless be investigated, and you have the impetus for the scientific method and from there the modern world.
And nothing highlights this more than exploring space e.g. the breakthrough starshot project to send a probe to alpha centari. It will use unimaginable energies to send a probe a fraction of a gram in weight at speeds far too fast for humans to imagine, but will take decades to get to alpha cen, travelling through basically nothing all that time, before zipping through the alpha cen system in a couple of minutes.
The point being: space isn’t meant for human perception of time or distance, and any space-faring species has had to adapt to that reality. And bear in mind how primitive humans are likely to be compared to the average sentient species (given how old the universe is). I doubt different perception of time is going to be a big problem, let alone an insurmountable one, when it comes to decoding a language.
This idea of a generation ship seems to leave out Darwin’s evolution: when the colonists reproduce in space they will fight against Malthusian problems, no idea how they will solve that, but whatever they do, they will have to cull most of the descendants and/or impose a strikt 2-child policy. And those children will be subject to genetic drift and to a completely different evolutionary pressure than humans on Earth, so after the 100.000 or 50 Million years that have been mentioned in this thread, whatever arrives at a far away destination will no longer be the humans we know, and if they send two ships, there might be two new species. So when the whole galaxy is colonised, it will not be colonised by a single species, but many different ones. And whatever they take with them to eat will evolve as well: plants, animals, yeasts, funghi and bacteria. Evolving in such a small “island” as a spaceship for hundreds of thousands of years will be interesting but I have the feeling the results might not be only positive. Things you don’t “need” in space will probably be lost, but you might need them again when you arrive at a planet, but evolution does not retrace her steps.
Most of the arguments imply that the emergence of life (and more so complex life) in earth-like conditions is very, or at least somewhat, probable. This may not be true by orders of magnitude so that life on earth could have been an entirely quirky event. We may very well be alone - or de-facto alone - if a civilization exists 10 million light years away, it does’t change the loneliness situation.
These languages say otherwise.
The reason we can translate languages between different human societies with relative ease is because despite differences in grammatical structure and culture, we all have a generally common experience of the world and close analogues in every human society, notwithstanding sharing the same essential physiology and perception. For instance, not every human society or langauge has the same division of the ROYGBIV for the visible color spectrum of light, but all have some graduated description of colors that can be interpolated to make an approximation. But an alien intelligence that sees the world in different wavelengths, or perhaps using some wholly different means other than visible light, and may construct in interior image in a very different fashion may have no conception of what “color” means even if explicitly defined in terms of electromagnetic wavelength any more than we could intuit the different “hues” of two different bandwidths of radio-frequency spectra. And more importantly, the inborn emotional responses human beings have to color—which are largely biologically innate, even if affected by societial memes like the gender associations of pink and blue—are going to be completely incomprensible to an alien intelligence because there is no expectation they will have anything like the same evolutionary development and construction of the underlying affective aspects of cognition.
All human beings experience the world in terms of approximately 1/20th of a second (hence why the 24 frame per second speed of a projected film image looks seamless unless the camera is panning) and parse grammar in terms of individual actions in subject-predicate form that fit into that timeframe or multiples of it, regardless of the order of nouns, verbs, adjectives, prepositional modifiers, et cetera. An alien lifeform that experiences the world in a much slower rate—say, on orders of minutes or hours due to a much slower biochemistry, or perhaps on the rate of microseconds because their construction is based on high frequency electrical circuits in some kind of a self-replicating semiconductive substrate rather than our slow electrochemical potentiation—will almost certainly have a very different cognitive construction of the world and even in how causality works at a detail level.
Something that should be understood is that our perception of the world isn’t based directly upon information taken from the senses, but instead is constructed internally based upon sparse and sometimes seemingly contradictory information which the brain corrects and fills in with made up “perceptions”; this is what makes optical (perceptive) illusions work, and some people describe the experience of apparent direct perception as a “hallucination”, which is not wholly inaccurate (although what we think of as hallucinations typically involve radical distortions of perception combined with concepts drawn from imagination). In other words, what we ‘observe’ as the outside world is essentially something our brains have constructed, and not some kind of objective experience that any organism with a different cognitive physiology would experience.
This is true, and in fact, we cannot really perceive the underlying physics of the world using our brains. At best, we understand the basic mechanics by analogy to things we can directly experience, but those analogies break down and we have to resort to using the very non-intuititve mathatmetics of tensor field equations and C[SUP]*[/SUP]-algebras to try to make useful predictions. In the future, we will likely become reliant upon specialized machine intelligence using quantum logic to cope with the massive complexity of high degree-of-freedom quantum particle systems, which will further distance us from the sort of fundamental mechanics that might provide some universal shared basis for knowledge.
In the science fiction literature and television/film portrayal of aliens, they are often assumed to be essentially human (similar senses, familial experience, biochemistry, et cetera) with just particular cultural or biological quirks that distinguish them; only rarely is a truly alien species is presented, even though from an evolutionary standpoint it is highly unlikely that of all particularly paths a bisexual humanoid species would arise from any general form of life, much less than that it would be so alike as to share a common language or be able to interbreed as commonly portrayed. In fact, if two different societies managed to develop at the same rate at the same timeframe in sufficiently close proximity to communicate, much less somehow physically interact, it would be a coincidence of literally astronomical improbability unless technological societies emerge on every possible world.
Something else that should be pointed out is that while the common assumption is that life will most likely (or only) arise on “Earth-like” planets within a theoretical habitable zone about a star where liquid water can exist on the surface; however, although that is true of Earth, it may not be the most probable scenario. In fact, there is good reason to believe that life may be far more common on planets or moons with an ice-covered surface and underwater liquid (water or hydrocarbon) seas heated by tidal or radioactive decay sources. Whether intelligent, technological life could develop on such hypothetical reservoir is unknown (and without more evidence, really unknowable) but if it did it would certainly look very different and have a vastly divergent technological basis.
The emergence of life falls under a corollary to the Law of Large Numbers; that if there is any statistical likelihood of all of thermodynamically self-regulating life spontaneously emerging from an organic (or other) substrate, it should be arising all over the place just because of the vast number of suitable environments and the long duration of time for occurance. However, we do not know (and without more evidence, cannot infer) as to how long such life may exist, how far it may develop, and how frequently it may encounter extinction-level events (which is an argument to bolster the notion of life arising under the protective cover of surface ice and a subsurface ocean where it will be protected from the vagaries of atmospheric phenomena and charged particle radiation from more energetic and more variable stars such as M and K spectra stars that are more common that our G or F spectra stars and appear likely to have large and widely varied planetary systems.
Stranger
While it won’t change a persons personal decision related to if they choose an optimistic stance on the parameters of the Drake equation or assumption on the inevitability of future breakthroughs in physics here is some documentation from the people who had this conversation with Fermi that may be interesting to several of you.
I get that the apparent paradox that people like to ponder is not really tied to Fermi’s ideas at the time but it is interesting to read and to note that it was a non-sequitur during a lunch time discussion about a cartoon etc…
It is an interesting read or me at least but I fully admit that I may enjoy it because I agree with Dr. Enrico Fermi’s conclusions more than the typical modern conclusions which happen to be intriguing enough to be publicized. Hopefully others enjoy it and to be clear again I am not making any claim that thinking about it is in anyway a waste of time or wrong, just that it is understandable that one needs to invoke optimistic ideas or resort to concepts that are really fiction right now to move past Fermi’s conclusions (It is more correct to say the conclusions his peers remember him making).