This is full of ridiculous assumptions. Probably the worst one is the idea that a sapient species that's capable of colonizing space and maintains that ability and attitude for such a long term that other sapient species can arise won't colonize every available star before any other species can do so. Thousands of species occupying separate yet touching volumes of space is mind-bogglingly unlikely.
I think that’s attacking the conclusion, not the assumptions. Have you put numbers on what you consider “mind-bogglingly unlikely” and done the math on that, given the distances involved?
The authors supposedly have, and I’m no expert, but I don’t find the argument completely ridiculous. The universe isn’t that old compared to its size; I think it’s plausible for two unlikely events to have happened without their causal cones having intersected yet.
This is too simplistic a critique. One species colonizing everything is perfectly compatible with the model in the broad. The complication is that we ourselves exist, are not colonized, and can look out into space and don't see any alien activity. Hanson starts from this anthropic fact and tries to reason about what we might be expected to see if a) there are "grabby" species out there, and b) we're early enough to witness the land grab. I have problems with the details of the model, but I think it's both a fruitful and interesting attempt to think about things.
Reward-seeking intelligences might have innate features which prevent exponential expansion though and instead result in expansion-contraction loop. For example, for every new colony, the probability that any single colony will begin a civil war may increase. Or the probability that a supervirus will be manifested somewhere and then spread along the galactic population of that species. Basically, if the species are uniform in some manner, the more colonies they have the larger the probability that some colony will spawn an event which utilizes their uniformity to spread and destroy most of the galactic population of that species.
Obviously it's not a guarantee, but I believe it is a viable theory as to why the world described in the article may be possible.
I don’t think that matters much for the distances we talk about. Any such disruption — even if it’s a new philosophy or religion that makes the colonies stop spreading — would only travel at the speed of light, which means that it would take a long time to reach the frontier of a civilization that expands at nearly light speed.
> While the current date is 13.8 billion years after the Big Bang, the average star will last over five trillion years.
That's mostly true but also not quite.
The longest-lived main sequence star will have a lifetime of about 500 billion years, the shortest just a million.
The only stars that are likely to live into the trillions are red dwarves, which are very common but which have very small habitable zones due to their feeble output.
I suppose if we take the philosophical position of Bayesian statistics, where even one sample is sufficient basis for estimating results from some sane priori model, I would say this topic is within reach of some sane postulation. Some factors we can take into account:
1. Life can evolve into us. Therefore life on other planets has p>0 to evolve agglomerations of matter we would call "alien civilization"
2. Evolution seems to be driven through external constraints, and seems to generate similar structures to solve similar problems. Hence it's not insane to postulate organelles and their function are a particular energy minima to a complex set of constraints - ie. evolution on any earth like planet might reach similar patterns as earth life.
3. Neurological function seems to be driven by laws of mathematical dynamics up to a point - if it's math, we will see it everywhere in the universe. What sort of math - I suppose nobody completely understands yet.
4. I use the above to postulate that familiar modes of existence and familiar neurological function can emerge anywhere in the universe
5. If a species is to survive, it needs to have innate drive to do so. Unless species innate drive to survive perishes, an intelligent species will realize it's chances of survival are better if it is not limited to one planet. Then, one solar system and so on. Therefore we can postulate a "natural tendency" to start interstellar expansion.
6. Humans have already launched an interstellar space craft (Voyager). Therefore p>0 that life can evolve to develop vehicles that exceeds the escape velocity form their home star
Or something like that. The thing is, I don't understand the problem well enough to know if it's impossible to probe by statistics or not. I just know I'm not smart enough to solve the matter - when I did a course on Bayesian statistics the thing that left me astounded time and again was that one could create sane and accurate models from incredibly thin amount of data if one just had a good enough grasp of some of the factors at play.
> If a species is to survive, it needs to have innate drive to do so....
It's worth pointing out, that's not how natural selection works. NS would be: If a species has an innate drive to survive, it will do so. Yes, subtle. But essential.
That aside, how would you account for an asteroid strike?
I suppose it isn't, but the categorization is a bit different. For example, Drake takes a concept called "civilization" as given, wheres I stated it's plausible extraterrestrial life would take similar pathways as in terrestrial evolution, and that other terrestrial species have minds that give them in some ways behaviours quite similar to our own (hence increasing the likelihood of extrasolar life having familiar characteristics). The categorizations I listed were in the "self organization emerging from complex systems" tune of things while Drake equation is a bit more hierarchical. But yes, same thing I guess.
For 1, Life has more chance to evolve in milliona of other species that dont o serve space, master fire or launch rockets. pretty bad odds once you look around you. plus we have been graced by having fairly mild cosmic conditions for a long time. other planets may not be so lucky
Sure, but space is mind-bogglingly large. Our galaxy alone has hundreds of billions of stars. Even one in a billion odds ends up with hundreds of systems that develop just like ours did. And that's just one galaxy out of billions.
That however circles back to space being large. While a galaxy might host hundreds of civilizations just like ours at any given time, the distances between them can be insurmountable. Time is also pretty large so even a civilization that survives thousands or even millions of years might never overlap with another that they can contact.
Part of the problem is, you just need one civilization in this galaxy to invent von Neumann probes to expect to see their robot offspring everywhere, even if that civilization is half a billion years dead.
The word "just" is doing some pretty heavy lifting in that statement.
It pre-supposes you can event build a bunch of invincible perfectly programmed micro/nanobots in the first place. Then you can identify a target body in a solar system a long ways away. Then predict that system's position with an accuracy your probe could land on it after a trip of hundreds of light years (or launch a probe with a bunch of fuel to do terminal maneuvering). Then those probes would function after millennia of dormancy.
It's all possible. But the concept shouldn't be treated as inevitable.
It also runs right up against panspermia theories. What's the practical difference between a single celled organism and a self-replicating nanobot?
Well, yeah. It's really hard to do, so maybe nobody does it, or it's just impossible. But with several billions of years of galactic history it has to be pretty hard if civilizations are common.
Really it's just one example of a technosignature that is longer-lasting than radio waves, that extends the amount of detectable overlap we might expect to have with an older civilization, and the lack of observation either says that sort of technology is either not feasible or there aren't many civilizations in the galactic past or present.
> I suppose if we take the philosophical position of Bayesian statistics, where even one sample is sufficient basis for estimating results from some sane priori model...
Some care should be taken to see that this principle is not being used to excuse just making things up. Bayesian statistics is rational but not magical, and it cannot create information out of nothing.
In practice, this comes down to the question of whether the model is plausible, accurate, complete and constrained enough to deliver an answer that is informative about the external world, as opposed to the choices made in modeling. Something more than reasons to believe various probabilities are non-zero is needed.
I feel that, in your final paragraph, you are grappling with this issue.
I totally agree with you. My intent was not to promote pseudoscience but just to try sketch out why I don't intuitively feel the question would be totally beyond the scope of rational discourse.
> 1. Life can evolve into us. Therefore life on other planets has p>0 to evolve agglomerations of matter we would call "alien civilization"
In any universe that we can observe, we must exist. That strips away any useful a priori probability estimations about how likely we were to come into existence. p ~= 0 is still p > 0. There could have been a trillion trillion trillion trillion universes before this one where no life evolved that we would never know about because we were not around to observe them. And there could be a trillion trillion trillion universes after this one in which no life arises.
I think this in the category of things that would be plausible to estimate. AFAIK there has never been a Manhattan Project level investment in abiogenesis.
Of course there are quite a few steps from suitable RNA synthesis mechanism emerging to LUCA.
But until we get CERN level investment into research on abiognenesis I don't think the matter can be considered impossible to solve.
The outcome might very well be that chance of life emerging is close to zero (I don't believe it, but it's just a belief, nothing more). At this point we can only conclusively say more research is needed.
If someone is in the field I would love to hear recent details.
Agreed. This is irresponsible science communication --- and at a time when public understanding of and trust in science has been dropping significantly.
This feels like circular logic to me. "We are early because later on the universe will have been colonised", but we don't admit "We are not later alien members of a grabby species because... ?" By the logic in this argument, it should be "fishy" that we're not aliens living at a later stage of the universe, so I don't think this theory is complete.
I was playing EA NHL a lot when I was younger. What I noticed was that there were more than average goals in the last minutes of the game than in the earlier minutes of the same game.
I always wondered if this was due to a badly implemented stochastic model. Since if the average goals per game was lets 5 and the score was 2:2 the likelihood of another goal would increase in the last minutes.
This is how this argument feels as well.
So first they say we are unlikely early. But if you consider that we are special (“grabby”) then that’s ok. Somehow like saying there would be another US like country in Europe if the Mayans were developing faster.
> So first they say we are unlikely early. But if you consider that we are special (“grabby”) then that’s ok.
I don't think that's their reasoning. I think they say:
1. once grabby civilization appear - it decreases likelihood of other civilizations appearing
2. so actually weighting by probability we're not early - we're average, because the probability of appearing late is almost 0
This kind of backward probabilistic reasoning always felt like cheating to me, especially when it's not only used to validate our models but to create them.
As for NHL I don't know, but in football (soccer) 75% of goals are scored in first and last 5 minutes of both halves, and the single most likely period to score goals in is the final 5 minutes of the last half. So it was maybe realistic :)
Re the article: yes, I understand their reasoning. But isn’t it like saying: if we were to become a greedy civilization THEN in the future we would think how good that we were early…
Until we have just one datapoint from another civilization or planet (just one!) every single statement surrounding Fermi paradox stuff can't be proven, for example:
- Life has to go through "hard steps" to get to civilization
- (I really hate this one at a personal level for multiple reasons) assuming alien civilizations will use Dyson spheres
- There exists some sort of 'great filter' that prevents civilizations from expanding
For each of these, we have absolutely no data to compare to in order to support or refute these statesments.
To be fair the fermi paradox itself doesn't make any conclusions and only relies on the drake equation.
Saying "if the drake equation holds up, then why is it so quiet in the universe?"
As soon as we have one data point from another civilization, the paradox automatically disappears. It's only in the absence that we can ask the question, and speculate.
There's no data but to the best of our scientific knowledge, this is how the universe works.
Life is hard. We know that because it took billions of years from the first self-replicating molecules to us. We also know there are things happening in our solar system that wiped us out. We know we could have wiped our species out ourselves.
The "great filter" is one theory to explain why on the one hand we should be observing other civilizations, but we don't. Also they don't need to use Dyson Spheres exactly. But before they start expanding in earnest, they would have a measurable effect on the emissions coming from their star, as perceived from other stars.
The whole reasoning seems to boil down to one of the standard answers to the Fermi paradox: We did not encounter any alians, because we are in our stellar neighbourhood either the first or anyone else is hiding. To "explain" that, we need to reason about the Drake equation, or rather a modification of it, since the original Drake equation did not include the possibility that an alian species colonizes other solar systems. In our context the question is at what time in the history of our galaxy colonization might start (if ever) or might have started and what the typical expansion rate is. Something like the Grabby Aliens simulation can only teach us how such a presumed colonization might proceed roughly under the most simplified[1] model. But it seems to tells us next to nothing about the parameters to fill into the (modified) Drake equation to solve the Fermi paradox. -- Or did I miss something?
[1] I do not think that the simplifications are problematic, as long as one is aware of them. It is rather the opposite: Running a simulation with a simplified model helps us to observe some basic principles at work. Later we might refine and enrich our models and simulations. To use an analogy: If we want to study the movement of objects under the influence of the Earth's gravity, we should start with cannonballs and not with feathers.
The problem with the dark forest / everyone is hiding explanation is that you can't hide.
For over a billion years Earth has been broadcasting a very powerful signal screaming "likely biosphere here" in the form of its albedo spectrum. It's a wet, warm planet that for almost two billion years has had a heavily oxidizing atmosphere. There are few natural explanations for that that don't involve life, since it strongly implies that something is doing work to maintain an energy differential.
If there are "reaper" aliens around in any form, it would be logical for them to start firing relativistic kinetic weapons at any candidate biosphere immediately. Why wait for intelligence to even get a foothold? Just whack any potential competitor while it's nothing but goop and creepy crawlies.
So if there are ancient powerful hostile or "grabby" aliens around, we should not be here.
It's a pretty powerful argument for one of:
(1) We are very early.
(2) Intelligent complex life is extremely rare, occurring less often than e.g. once per galaxy per ten billion years. (A bit different from being very early since it implies we might never find another even after billions of years.)
(3) Something weird is going on, e.g. our solar system is being kept as a wildlife preserve and/or there is a "prime directive" or something.
(4) Something even weirder is going on, which explodes into a long tail of possibilities. Maybe we are wrong about our basic cosmology. Maybe continued advancement in intelligence leads places very different from space flight such as traversing dimensions or converting oneself into some more exotic form invisible to us (like the "ascension" trope in sci-fi). ... and so on.
(5) the great filter is between simple life and complex life - so it's not worth it to preemptively strike at every complex life candidate because there's too many candidates
As good an explanation as any: I like to imagine God is really lonely, and we are in a specifically constructed empty universe with one life bearing planet for the purpose of evolving God a peer. It's lonely on top, ya see.
Why is this greyed out? If you say aliens got lonely on here people will engage you, but if you say God got lonely you get downvoted. Honestly though, these discussions are talking about things past our knowledge. An intellectually honest discussion should be able to include this stuff.
It reminds me of people who hate the idea that a omnipotent being created us, but are fascinated by the idea a hyperintelligent being simulated us
Evolution has no endgame, so the precise moment you assume any kind of endgame (especially an "obvious" endgame), the discussion becomes non-intellectual and unworthy.
Also, if you want to discuss what God is or wants of us, pick a God and we can discuss, based on holy books and revelations, what His/Her/its intentions may be. Just saying "God" doesn't mean anything at all - there is little similarity to be found for example between YHWH, Brahman, and Amaterasu that could see a meaningful discussion.
Aliens are, by definition, hypothetical beings that are similar to us in obeying the same laws of physics. God is, by definition, a transcendental being which exists beyond the laws of physics. These two ideas are fundamentally different.
In particular, speculating about what God may want (even if you believe one exists) is entirely futile, as it could want anything at all. In contrast, there are constraints on what an alien species could possibly be like - for example, we know with essentially absolute certainty that an alien species wouldn't eat quarks, whereas there is no reason to say that God wouldn't consume quarks.
Now of course, depending on your particular religion, you may have some things that you believe God told you explicitly. In no major religion though is God just lonely.
For example, in Christianity God created us and He only wants us to follow His laws; the notion that we could evolve to become akin to God is heretical - God is only one, and He demands worship and love, not emulation. For another example, in some versions of Hinduism, God (Brahman) encompasses everything, and we are already God - we can grow to understand this thing, but the very notion of a second God is entirely nonsensical, as God is already literally everything.
Well, the LDS/Mormon formulation of Chrisitanity is explicitly counter to what you're stating (which probably a good portion of why Mormon's are indeed considered heretical by most Christian sects)- that humans are spirits that existed prior to the earth's existence and God is just the greatest of those spirits and he's helping us along to reach his same status. I often refer to the religion as the first sci-fi religion.
From the Book of Abraham (an LDS scriptural text):
21 I dwell in the midst of them all; I now, therefore, have come down unto thee to declare unto thee the works which my hands have made, wherein my wisdom excelleth them all, for I rule in the heavens above, and in the earth beneath, in all wisdom and prudence, over all the intelligences thine eyes have seen from the beginning; I came down in the beginning in the midst of all the intelligences thou hast seen.
22 Now the Lord had shown unto me, Abraham, the intelligences that were organized before the world was; and among all these there were many of the noble and great ones;
23 And God saw these souls that they were good, and he stood in the midst of them, and he said: These I will make my rulers; for he stood among those that were spirits, and he saw that they were good; and he said unto me: Abraham, thou art one of them; thou wast chosen before thou wast born.
24 And there stood aone among them that was like unto God, and he said unto those who were with him: We will go down, for there is space there, and we will take of these materials, and we will make an earth whereon these may dwell;
25 And we will aprove them herewith, to see if they will do all things whatsoever the Lord their God shall command them;
26 And they who akeep their first estate shall be added upon; and they who keep not their first estate shall not have glory in the same kingdom with those who keep their first estate; and they who keep their second estate shall have dglory added upon their heads for ever and ever.
The founder of the religion spoke at a funeral and had this to say:
The mind of man is as immortal as God himself. I know that my testimony is true; hence, when I talk to these mourners, what have they lost? Their friends and relatives are separated from their bodies for only a short season; their spirits existed coequal with God, and they now exist in a place where they converse together, the same as we do on the earth. Is it logic to say that a spirit is immortal and yet has a beginning? Because if a spirit has a beginning, it will have an end.
That is good logic. I want to reason further on the spirit of man, for I am dwelling on the spirit and body of man--on the subject of the dead. I take my ring from my finger and liken it unto the mind of man, the immortal spirit, because it has no beginning. Suppose I cut it in two; as the Lord lives, because it has a beginning, it would have an end.
All the fools and learned and wise men from the beginning of creation who say that man had a beginning prove that he must have an end. If that were so, the doctrine of annihilation would be true. But if I am right, I might with boldness proclaim from the house tops that God never did have power to create the spirit of man at all. God himself could not create himself. Intelligence exists upon a self-existent principle; it is a spirit from age to age, and there is no creation about it. Moreover, all the spirits that God ever sent into the world are susceptible to enlargement.
The first principles of man are self-existent with God. God found himself in the midst of spirits and glory, and because he was greater, he saw proper to institute laws whereby the rest could have the privilege of advancing like himself--that they might have one glory upon another and all the knowledge, power, and glory necessary to save the world of spirits.
Moromonism is far from a major religion, by any measure. It's not even a major branch of Christianity (there are 17 millions Mormons out of around 2.8 billion Christians; for a comparison, there are 37 million Ethiopian Orthodox Tewahedo Christians, one of the few groups older than the Catholic Church).
Its a fairly major/influential denomination in the US, of which HN is mostly centered. Not arguing that it is globally influential- but it does have an interesting/unique theology relevant to the discussion.
> for example, we know with essentially absolute certainty that an alien species wouldn't eat quarks
Is that accurate? Clarke's third law and all that. Any discussion on what alien beings, or for that matter, some sort of hyper-advanced AI intelligence, ends up unbounded by the limitations of current human knowledge. People ascribe omnipotence and omniscience to such hypothetical entities all of the time, but also anthropocentric motivations.
See Roko's Basilisk which presupposes a future superintelligent A.I. is able to project back into history with perfect clarity, create simulations of sentient beings, and is petty enough to exact vengeance upon them. So you end up arguing about secular deities.
These discussions are fun yet wrapped up in non-falsifiability and woo.
It is - we would have to be so wrong about how the universe works for that to be possible that it would be absolutely miraculous that we can even make a fire, not to mention a particle accelerator.
People tend to significantly underestimate how little room there is for us to be significantly wrong about such things and still have all the observations we've made. There are still major gaps in our understanding of the universe, to be sure, but they are nowhere near the level of allowing for beings which strip quarks from a nucleus.
> (2) Intelligent complex life is extremely rare, occurring less often than e.g. once per galaxy per ten billion years. (A bit different from being very early since it implies we might never find another even after billions of years.)
I think a more practical take on this isn't life is rare it's that both space and time are big. Two civilizations existing simultaneously but 1/100th a galaxy apart are still a thousand light years apart. Each would see the other's home system as one of billions of observation candidates.
Even with massive SETI operations by both civilizations the odds of those two civilizations discovering one another are pretty small. Even if we posit advanced civilizations are more abundant, separated by only a few hundred light years, the odds are still very small any two civilizations will find each other.
Detecting "leaked" radio emissions just isn't a thing that can happen. The inverse square law make this plain. If we placed our most sensitive radio telescopes on a planet in the Alpha Centauri system we wouldn't be able to detect Earth's radio emissions save for rare blips where a powerful radar system's beam happened to point directly at Alpha Centauri. Earth would need a system of persistent ASETI transmitters aimed at specific stars to have a chance to have emissions be detected by civilizations there.
There don't need to really posit anything weirder than space is fucking huge to explain the Fermi paradox.
There are some science-y reasons in support of (2), though. Granted, we are biased by being familiar with human life, of course. Consider this: phosphorus is a fairly rare element out there. It's comparatively common on Earth vs. other parts of the galaxy, and "more common" is still somewhat rare on Earth. Yet, Earth life has gone out of its way to use phosphorus for some fairly key parts of itself (DNA!) despite its rarity. Maybe it's path dependence / weird luck, but maybe phosphorus really is that much better than other elements for such purposes. If phosphorus really is both very rare galactically AND key for the development of advanced life, that really does argue in favor of (2), that Earth just hit the cosmic jackpot for sustainability of life. (High phosphorus scarcity would also make interstellar colonization by humans a non-starter... we'd be stuck using robots to explore at best.)
1 - Given that we are only 14B years into a many-trillion-year stretch, our existence now is so unlikely that it's possible that we actually are the first. Something has to be first.
2 - Aliens are everywhere, but we cannot perceive them for reasons we would find disturbing. Largely, for the same sort of reasons that cave fish cannot see light or that most species are apparently unaware of humans in their environment. Essentially, that there is no evolutionary reason for humans to perceive them.
As for grabby aliens... meh. I don't find it convincing as a resolution. It contains too many unexamined assumptions, quite like the simulation theory.
I'm betting on #2. We only have our own planet to look at, but if we could somehow rank all of the species on the planet according to intelligence, just jumping a couple of levels up or down you enter a completely different world of existence. Or as I like to quip, somewhere in the middle of the ocean there's an island. On that island is an ant hill, and there's an ant at the top of it wondering: Where are all of the other ants?
I don't really find it disturbing, though. Our "best practice" to interact with other species is to try to leave them alone and watch them enjoy and live in their habitat. Makes sense that's what we're doing for the alien overlords, and I'm okay with that. Assuming aliens are around somewhere and we're using our own planet to reason by analogy, the only other two alternatives are they're going to subjugate/destroy us or they're going to eat us. Those alternatives are not so fun.
I find it interesting that so many humans assume that since we can chat with one another, aliens somehow are supposed to show up and chat with us. It's all about us. If such a thing happened, the history of massively-different cultures interacting on Earth is not a positive one.
It's nice that someone else gets #2. I often get bogged down with people refuting the notion by pointing out that we are not cave fish and are nothing like cave fish. That we have evolved to perceive everything that can possibly threaten us and that includes aliens.
Thanks to technology we can perceive many things that we have no evolutionary reason to be able to perceive. Our current physics also doesn't seem to be _so_ wrong that it allows much room for technological societies to hide from our instruments.
> Thanks to technology we can perceive many things that we have no evolutionary reason to be able to perceive.
We might be able to perceive, but that doesn't mean we understand what we see. Every time I engage with medicine, I learn how little humanity actually knows, despite all the technology. We still don't understand what causes many diseases, or how to heal many wounds. How would we find completely alien life when we can't even find the cause of a disease that plagues 23% of the adult population?
You are missing the point, in our arrogance to believe we understand things, we do not really understand them. The drive to understand more is powerful, and has lead to huge advances, but we still have a long way to go.
I agree that we still have a very long way to go. I disagree that the areas of the universe that are still mysterious to us are likely to be hiding places for aliens.
Sometimes, you have to wait until you're dead or dying to know they exist.
I'm not convinced that humans have mastered perception after mastering writing 5 thousand years ago.
You're partially right, but missing something important.
Where you're correct: Aliens that are only found on planets would be almost impossible to spot, and even if we look at them and see the consequences of their existence on their atmosphere we may interpret that as non biological in origin.
What you're missing: However, if they are expansionist and can build space habitats and automation of the sort we have reason to believe is possible, the question is "why are there visible stars? Why are they not all already surrounded in Dyson swarms?" which is hard to miss regardless of underlying chemistry or biology.
So far as we can currently understand, it seems that about 96% of the matter-energy of the universe is stuff that we cannot see, detect, or explain. Dark matter/energy.
There's more than enough room for fanciful explanations.
Except that dark matter doesn't even interact with itself. Particles of dark matter just pass right through each other rather than clumping together to form complex molecules, rocks, planets, etc.
A Dyson swarm emits approximately same energy as its host star, just in infrared. Dark Matter could, I guess, be Matryoshka brains organised carefully to not hit each other by their keepers, so long as they are also actively "gardening" what we can see so they never ever get Dyson-d.
Wrong isn't the same as incomplete and we have a weird tendency to overlook things, we find then "obvious" afterwards.
Things we do not easily perceive are such that are too fast, too small, too high energy generally and, most importantly, too unexpected.
Further, you can hide in plain sight: you only have to look "unbelievable" (for example), so society will not transmit the information of your sighting.
You can hide where (nearly) no one is looking as well: deep under the ocean, far below the surface, high in the sky, etc.
Most likely, this isn't exhaustive. Places we don't know about are perfect for hiding ,-)
Yeah, we are at the point that we are getting data on black holes colliding millions of light years away from us based on the deviation of a Lazer across miles over the width of a few atoms.
To suggest the universe is full of life and we simply can't see it? I don't buy it.
I think it's more likely that the signals just aren't there, because they are... Not hidden, but are too weak and crossing too grand a distance to be detected.
There are plenty of things that we are aware of that are currently impenetrable by our instruments, such as the inside of black holes or the past. And who knows what we aren't aware of. Is there any reason to believe that physics is a complete description of reality? Or even a significant slice? It could be just describing a very tiny human centric slice of all that exists.
Dark Matter and Dark Energy make up 95% of the Universe (the rest is all the normal matter and energy in all of the galaxies put together). Our understanding of physics is both very complete, and contains large unknowns. You might imagine that there are a lot of aliens hiding in the Dark Matter, but as far as we can tell Dark Matter particles pass right through each other, as well as normal matter. They cannot clump together to make stars or planets or life forms the way normal matter can. Thus all aliens would be made of normal matter like us.
I’m sure I could find some, but I haven’t bothered.
We know that our current understanding of physics is incomplete (various niggling little problems with the Standard Model, the whole Dark Matter question etc), but these are surprisingly small problems. We only know about these problems because of the extreme sensitivity of our instruments. The new physics that will eventually fill these gaps will answer fascinating questions, but won’t change anything about our understanding of life.
For example, petaquarks were first observed in the early 2000’s, and the Large Hadron Collider provided additional evidence for their existence. But they’re so unstable that they can never stick around long enough to participate in any life processes, so as far as our understanding of aliens goes they are irrelevant. Maybe they exist naturally inside the cores of neutron stars, but that’s not really a very habitable environment.
Similarly, however we resolve the apparent paradoxes in our understanding of gravity and quantum mechanics won’t matter at all to the study of life. Gravity is so weak that it is essentially irrelevant in any sort of chemical system, even when quantum mechanics is necessary to understand the fine details.
What I mean is, "complete" according to what criteria? It seems trivially obvious that our human model of physics could only be complete in the sense of accounting for all things we are capable of observing, but that isn't the same as being able to account for all things. There is nothing I am aware of in the model of physics that claims that it accounts for all aspects of reality, observable or not. We don't even know if there are multiple universes, and to what degree they interact, and if there are universes that mostly don't interact with ours at all. There is nothing in physics that precludes another universe that normally doesn't interact with ours, but advanced conscious beings within it being able to bridge that gap if they so choose, similar to how we could go to some island to visit an ant hill if we so choose.
On that last point you are incorrect. The known laws of physics rule out all forms of Einstein–Rosen bridge (aka “wormholes”) that you might imagine, except possibly inside of black holes (and those wouldn’t be traversable). That includes wormholes between points in our own universe, and between universes. Einstein and Rosen studied them because they are technically a valid solution to the equations of General Relativity, but not all solutions to those equations are realizable. In this case, opening a wormhole requires a considerable quantity of negative mass, and there is exactly zero negative mass available. Mass (or energy density), is simply never negative.
As for completeness, each revision we make to the known laws of physics is always smaller than the ones that came before. Einstein’s Relativity trumped Newton’s laws of gravity and motion, but only at high speeds or energies. At high speeds you start to notice weird effects like time dilation, but at low speeds the time dilation is so small that you would never notice it unless you knew to look for it.
Likewise, in most situations the difference between classical mechanics and quantum mechanics is unobservable. There were some edge cases where classical mechanics just couldn’t explain observable phenomena, like the photo–electric effect or phosphorescence, and all quantum mechanics does is fix those edge cases while still being able to explain all the rest of chemistry and such that we already knew about. The changes introduced by Quantum Electro–Dynamics and later Quantum Chromo–Dynamics were even subtler than that. The only easily–measured thing that QCD explains that QED couldn’t is radioactive decay, which is basically irrelevant to life. QED is much more useful to biologists because it explains how chemical reactions can release light (fireflies!), how chemicals can be sensitive to particular parts of the light spectrum (think rhodopsin in the cone cells in your eye), etc.
Because every new addition to our understanding of physics must not contradict anything we already understand (if it did then we would know it was wrong), we are asymptotically approaching a limit (as it were). That limit is either the full laws of physics, or I suppose you would say some limitation of our own minds. But why should our minds be unable to comprehend the full laws of physics? Even if those get harder and harder to learn about and understand, we have all the time in the universe to come to grips with them. Any individual can maybe hit a limit of how clever they can be, but the human race as a whole? I doubt it; we’ll crack that nut eventually. Even if humanity gives up at some point, nothing that we fail to learn could contradict what we have already figured out.
I wasn't talking about Einstein-Rosen bridges. In fact I was wary of using that analogy because I suspected, correctly, that it would be misunderstood.
It sounds like you are saying that any possible reality could only interact with another one using Einstein-Rosen bridges. This is far too narrow a limit of what is possible. If it's possible at all, regardless of likelihood, that reality could be a simulation, then anything you say about the Einstein-Rosen bridge is a property of the simulation, and not a limit on reality as a whole.
What we _can_ observe rules out a lot of things that we can not observe. For example we know to very high confidence that there is nothing that we can't perceive that influences the way nuclear reactions happen.
> Our current physics also doesn't seem to be _so_ wrong that it allows much room for technological societies to hide from our instruments.
Perhaps.
An idea I first heard from my brother a decade or two ago was that the Dark Energy expansion of the universe might be the waste product of all the aliens who figured out some way to trick the laws of physics into giving them free energy.
(Obviously that's more of a sci-fi plot device than science at this point, take it with the due level of seriousness).
Nothing new here. People always thought they already know "everything that's important" and "only a few details are missing". We, as a species, are quite arrogant and entitled to our perceived "large knowledge".
That's why real progress is so slow even "things are obvious"—at least afterwards.
I understand #2. I hope you understand the people refuting it.
Humans haven’t evolved additional perception, we created it. We evolved to see electromagnetic radiation in the “visible light” spectrum but we created tools to see every other part of it.
We’ve even created tools to accelerate matter to just under the speed of light, smashed atoms together and then detected the particles created from the collision.
We’ve explored our entire world, launched telescopes into space, sent probes outside of the solar system and so much more.
Can we see everything? Not even close. But our vision today is incomparably far compared to even just 150 years ago. Cave fish today see as well as cave fish 100,000 years ago.
Only, having the possibility to use such sensors isn't the same as actually using them.
Most advanced sensors are exceedingly rare and consequently locally far too restricted to be useful in this context. Social hurdles apply.
The most comprehensive sensor network on earth belongs to the US military.
In spite of being provided extraorinary amounts of taxpayers' money for this, the resulting data isn't shared for common interests like science at all.
We barely see neutrinos, we don't even know what dark-matter and -energy are, we can't reconcile micro and macro physics, we've lived for an eyeblink, we really don't have much clue.
Not referring to 300bps, as they seem to get it, but unfortunately many of the most unimaginative people limited by dogma also seem to be the most confident and condescending.
You aren't taking the analogy far enough. That fish doesn't have a prefrontal cortex, and can't even comprehend what we are capable of or capable of perceiving. Whatever more advanced being that us would have perception and experience that we aren't capable of comprehending. They would do whatever they do that we are incapable of just as the fish is incapable of human-level creation.
I think the problem is that 2 relies on kind of woowoo logic. Where exactly do these aliens exist in this scenario? WE can't perceive everything directly but with LIGO we're pretty close to being able to measure most phenomena that exist in the Universe. Is there a mirror universe they exist in because even if not directly we should be able to detect their influence on Solar Systems, Stars, Black Holes, etc.
> Or as I like to quip, somewhere in the middle of the ocean there's an island. On that island is an ant hill, and there's an ant at the top of it wondering: Where are all of the other ants?
That’s not a very good analogy though. The ants’ answer would be “maybe across the ocean”. And since the ants lack any tech to check or be checked by other ants that would be the end of it. It’s not naivety. If there were other ants not visible to the island, they would be fundamentally underdiscoverable.
Doesn’t matter. This is like asking where the other 21st century humans are in the universe.
Ants are co-existing with beings beyond their reach. They effectively have alien contact for the purpose of this analogy. The absence of other ants is just because ants are not tech savvy.
I'm highly suspicious of the fact that other life forms in the universe necessarily resemble our own, although I tend to think about some things that seem to be universal like the the laws of physics and organic matter. I'm not yet very convinced that the whole organic machinery revolving around RNA/DNA is universal, although I have a very deep feeling it is...
In any case, "The Caloris Network" is a reference example for me when attempting to think about how different alien lifeforms might be.
Is intelligence necessarily organic matter based? Maybe not. Maybe somewhere in the universe a spontaneous self-replicating turing machine appeared. Maybe there is life on the event horizon of a black hole, or maybe a hot type of intelligence lives inside a star.
I think we can make all kinds of wild assumptions.
Why? DNA/RNA is a very specific self-replicating machinery good for carbon-abundant places with liquid hydrogen oxide. It's like living in an old apartment and concluding natural gas fire from the stovetop is the universal form of fire, or something. Most aliens are probably tangled magnetothermohydrodynamic plasmas in star atmospheres or something.
Alternatively, given that the majority of the planet is water and we kind of can't really imagine a biology without it, the universe could be full of fish planets.
It is just the majority of the Earth’s surface that is covered with water.
If you go outside the frost line most of the mass of many bodies is water.
A generic outer solar system body (Europa, Ganymede, maybe even Pluto) has underground oceans. Inner solar system bodies have Goldilocks problems. Part of the Fermi paradox resolution may be that most life arises or will arise outside the frost line and those people will look at inner solar system bodies and assume out of hand that they are uninhabitable.
If there were grabby aliens of that sort (or even our sort) the real prize in our solar system would be worlds that have a good combination of ice and rock like maybe Ceres, Pluto, etc. To an interstellar species which runs on D-D fusion, it’s a fairly certain bet that you can find some ice world which can be disassembled and turned into a ‘small ringworld’ with a larger habitable area that a planet like Earth which might turn out to not be habitable at all.
I don't know why this hasn't come up yet, but watts per bit has fallen precipitously over the last 150 years, which means it's pretty unlikely we'd see any stray radio signals from other planets unless we managed to catch them exactly during their very brief 1-2 century inefficient stage.
And even if we're not in a "dark forest", keeping quiet is generally good social hygiene and tends to correlate with maturity. Which may be a side-effect of #2.
>If such a thing happened, the history of massively-different cultures interacting on Earth is not a positive one.
Given the sheer size of the universe, and the absolutely massive costs of interstellar travel, I have no idea why any alien civilization capable of visiting us would have hostile intent. Life is rare. Elements, even the rarest, are exceedingly common.
The thought that an advanced alien civilization would cross thousands of light years of distance to subjugate or destroy some naked apes is hilarious to me.
We've discovered super-earths orbiting around 11.8% of stars. These planets are 1-3x the size of the Earth (easier to detect), although we can only speculate to their elemental composition. We still don't know how many Earth-sized planets are out there, but they appear common [0].
A highly advanced technological society could even fuse hydrogen to synthesize the lighter elements in our periodic table. Imagine the sheer volume of hydrogen readily available in a single nebula (many stars worth).
If a civilization could climb enormous gravity wells, Jupiter itself has 318 times the mass of the Earth, ready for space mining.
The most likely reason would be to neutralize us before we can become a threat far far in the future. Subjugation could come in subtler forms, like in the book The Three Body problem where the aliens halt human scientific progress by stealthily interfering with science.
I've only made it part way through that series, but I also thought the premise there is silly. If you're a civilization capable of travelling hundreds or thousands of lightyears, you are, by definition a space native species whose natural habitat is the ships you build. Why spend such extraordinary amounts of time and energy when you could simply deconstruct a few lifeless rocks in your solar system? The universe is completely abundant with every element you could ever need, and life is so rare and precious.
The premise is the Dark Forest Theory where alien life doesn't share any evolutionary or cultural history (therefore intent is unknown), and technology advances fairly rapidly beyond a certain point, so other races become a potential threat. To survive the Dark Forest, it's best to assume hostility and either hide or attack first. Most attacks are done remotely with advanced physics instead of sending an invasion force. The Dark Forest is full of war and genocide, because most races reach the same conclusion. Take out the other before they can take you out. Or keep quite. Humans seem to be naive in that regard, doing neither.
Or...you can see Dark Forest theory for what it actually is: PRC propaganda.
It's fascist projection, applied on a universal scale.
EDIT: To expound upon this, I'm not really trashing Dark Forest theory. I mean, it's possible. But I find it to be deeply rooted in a particular brand of game theory that is convenient. I also find it's easier to justify genocide and other such things here on earth if you pretend the entire universe is out there doing the same thing.
As such, I hold the entire theory as suspect and someone trying to justify a particular mode of human existence. This extends deeper into the trilogy as women continually are painted as too soft and emotionally empathetic to make the cold hard decisions that will kill many humans but ensure the survival of the race.
This is a Very Big PRC Thing. "Someone must make tough, manly, destructive decisions and you will suffer because of those decisions. However, they are for the Greater Good of our Nation."
It's hard to take the theory seriously when it conveniently justifies the entire history of the PRC.
"Ask not what your country can do for you – ask what you can do for your country."
"All power to the Soviets."
I suspect most countries have some version of the same at some point in their history, encouraging their citizens to subjugate their needs/desires to those of the collective.
Interesting fact about that, those chapters are at different locations in the book depending on whether you are reading the original or the English translation.
In the original, they’re closer to the middle of the book, in the hope that they might evade the notice of censors. Whereas in the translation (at least into English), they were moved to the beginning.
I can’t remember where I read this, but I think it may have been an interview with either Liu Cixin or the translator Ken Liu in Clarkesworld.
> As such, I hold the entire theory as suspect and someone trying to justify a particular mode of human existence. This extends deeper into the trilogy as women continually are painted as too soft and emotionally empathetic to make the cold hard decisions that will kill many humans but ensure the survival of the race.
For folks who've only read the first book and might be somewhat confused, this specific set of values becomes crystal clear about halfway through the second book.
Ye Wenjie is too emotional. Which is a bit of a flip side of the same coin: she is presented as lacking in logic and ruled by emotion, much like Cheng is throughout Death's End.
Spoilers for Dark Forest and Death's End follow:
Cheng in Death's End makes several decisions:
1) As Swordholder she balks at transmitting the coordinates of the Trisolarians into the universe. Humanity is corralled into Australia and Mars to be starved until their numbers are more manageable by the Trisolarians. I vividly remember the flowery prose of how she just couldn't consign so many Trisolarians and Humans to death and that surely the Trisolarians would be the better choice. The prose is rather condescending of her choice. One hopes it's merely the translation.
2) One of the clues given to Cheng by Yun involves faster than light propulsion. However, it leaves behind evidence that can attract a Dark Forest attack. Cheng has Wade continue researching the propulsion but maintains the final say-so on if they proceed. The human government discovers the project and the choice is either armed conflict with antimatter bullets that'll cause a lot of death and destruction or to stand down. Her choice is to stand down and avoid conflict, this directly results in all of humanity (with the exception of her) that exists in the solar system being destroyed in the inevitable Dark Forest attack.
3) Cheng finally gets to make a "moral" decision and leave the pocket universe to try to ensure the universe cycles into another big bang. It is interesting because technically the decision is almost certain to not work: it depends on all the other residents of pocket universes also leaving and reentering the dying universe. It's almost like at the very end Liu Cixin gives this tiny concession so no one can be like, "Bro, what's your problem with women?"
There's an entire thing at the start of the book where Liu Cixin spends an inordinate amount of time describing how effeminate "peacetime" men are. It gets creepy and quickly becomes obvious it's a very personal takedown of Korean and Japanese men. Later, during the bunker era, Liu Cixin spends an equally inordinate amount of time singing the praises of tough, masculine men during a time of hard decisions made in the name of survival.
He just continually uses Cheng's empathy and (rather unbelievable after her mistakes as Swordholder if I'm being honest) naiveté to kill huge swaths of humanity. It's fairly obvious what his opinions are.
The whole message of "we need people to make tough (borderline genocidal) decisions for the survival of our people/race" is weighted so immensely, you get brow beaten by the author. It moves well beyond the norm for even military sci-fi, much less hard sci-fi.
EDIT: Also Luo's arrest after he steps down from being Swordholder for crimes against a star system that wasn't even known to be inhabited at the beginning of Death's End is ... the most blatant and ham-fisted critique of Western Woke-whatever I've ever seen. It's good, don't get me wrong. But it's just so hilariously obvious what Liu Cixin's bone to grind was.
I find it difficult to give him a pass for writing "bad things" about the Cultural Revolution when he ends up at the same fascist conclusions.
I'm not saying not to read the book. I don't actually regret reading the entire trilogy. It's got a certain nostalgia for the clumsy hard sci-fi of the 70s. However, I don't feel the trilogy does much to really extrapolate the Dark Forest theory so much as co-opt it to validate a set of ethical and political beliefs.
Or he's just critiquing the rationality of those different choices given the game theory scenario, using standard (even lazy) tropes / stereotypes to make the plot go. I didn't read it as propaganda or commentary but maybe I don't know enough about the cultural context (call me a cave fish from up thread).
I completely disagree with your last statement - Dark Forest theory is just another sci-fi plot device invention... One that people have been too ready to embrace as a real theory (or even the real universe) because it sounds smart.
But these debates are why literature majors exist :-p
My favorite version of "what would drive interactions between alien species" is "The Cold Equations" in The Eschaton Sequence (starting with Count to a Trillion).
> The Three Body problem where the aliens halt human scientific progress by stealthily interfering with science.
I remember reading a sci-fi short story (this was in the 1960s) in which a scientist started to suspect that hidden, hostile aliens were behind the tendency of productive researchers to get diverted into bureaucratic meetings. A couple of Google searches didn't produce a title. Maybe Theodore Sturgeon?
> I find it interesting that so many humans assume that since we can chat with one another, aliens somehow are supposed to show up and chat with us. It's all about us. If such a thing happened, the history of massively-different cultures interacting on Earth is not a positive one.
We do have terrestrial aliens here on Earth and we are trying to chat with them. Dolphins, Gorillas, Chimps, Bonobos, Crows, Killer Whales... there is evidence for all of these species having varying degrees of language, culture, problem solving capabilities. Some of them, like Dolphins, sure seem damned close to our own capabilities with likely fully formed languages. We've been trying to decipher their language for 50 years with almost no success. With many of these species we've figured out pretty rudimentary and simplistic communication modes, but they clearly have much more complex communication structures among themselves and we've come nowhere close to deciphering them.
That alone tells you how difficult it's going to be to learn to talk with extraterrestrial aliens. Even our near cousins, we struggle to communicate with.
If we're examining our behavior as an analogy for the ET's however, it would suggest that either no one's around, or those who are around are so advanced that they don't think we're worth the effort to communicate with. Because we're definitely trying to communicate with the species we're aware of that we think have language.
Of course, many of the species on that list were only added relatively recently (Crows, for example).
> Some of them, like Dolphins, sure seem damned close to our own capabilities with likely fully formed languages ... Because we're definitely trying to communicate with the species we're aware of that we think have language.
This is highly doubtful. Crows don't have language anything like humans. Dolphins are a more likely candidate. I want to believe it, but I can't.
And this right here is why it's taken us so long to figure out that we even have terrestrial aliens with cultures and languages.
If you're not willing to believe it's possible, then you can't even begin to devise ways to determine if it's real.
> "We have hardly begun to decipher the language of the raven. Its dictionary so far contains but a few 'words'. Perhaps our analysis has been too coarse-grained to catch the meanings. Our research has been something like that of aliens from outer space who make sonograms of human vocalizations under different situations - eating, playing, loving, fighting, etc. Certain differences noted in frequency, intonation, and loudness are correlated with feelings and emotions. But human sounds convey much more, and perhaps ravens' do, too."
> Our challenge is to put ourselves in the place of those "aliens from outer space" and solve the immensely difficult problem of how to communicate with another intelligent species.
Consider this: Crows pass knowledge down the generations. There have been studies done on crows where researchers go out and bully them. Then they observe the crows to see if they remember who bullied them. They do remember. And so do their children, and the children of their children. They clearly have a means of pretty abstract communication, because in remembering, they differentiate different people. They have a way of telling their kids "See that human? Yeah, that one. He's an asshole."
> Recent studies have proven that the crow can remember the faces of other birds and even humans. They can differentiate between those who have been kind to them and those who have caused them stress. Crows will even pass this information on to other generations.
With Dolphins the existence of a language is even clearer.
In this Nova Science episode they show clear evidence of a language. They have taught the dolphins to create a new trick (something they haven't done before and haven't been taught to do by humans). They've also taught them to do tricks together. Then they put them together - "together", "create". And they did it, they came up with a new trick and they did the exact same trick together.
> Then they put them together - "together", "create". And they did it, they came up with a new trick and they did the exact same trick together.
> That absolutely requires language akin to humans.
I want to believe they describe the trick like skaters describe theirs: "When I give you the signal, let's do a a 360 Ollie underflip flamingo powerslide. If we do it in sync, the walkers will give us treats".
#2 is not satisfying. The ant might not perceive humans but if the ant is not "special" then the ant should perceive tons of other life forms equivalent to its own level, across the islands that it can observe.
Resolving the Fermi paradox by appealing to hypothetical aliens who are too high for us to perceive just feels like "aliens-of-the-gaps". The number of species on Earth with human intelligence (and quantity of such individuals) is orders of magnitude less than the number with ant intelligence. Aliens more advanced than us should similarly be that much less common than us. If humanity is not special, other aliens who are more equivalent to us are still missing.
I mean, in this age we are still discovering super strange weird stuff on the atomic/proton/electron/quark scale, so maybe we need a lot of more time to discover other super strange weird stuff on the galactic/universe level as well.
In my understanding the only hard assumption in the grabby aliens hypothesis is that there is a chance of a civilization becoming "grabby" by which they mean it sprouts new civilizations in neighboring solar systems. Everything else is just necessary simplification. It even accounts for civilizations not becoming grabby.
And the grabby hypothesis predicts we are quite early.
As a teenager I read Heinlein's 'Goldfish Bowl' [1] and it was the best explanation apart from the one from Stanislaw Lem I had heard for the lack of aliens. Namely that: you can't 'see' them because they're just too different.
Heinlein doesn't even make it clear if the higher intelligence in his short story are aliens or from Earth.
I think Lem's explanation (don't remember in which book/short story of his) was that the window where a civilisation is not advanced enough to learn something from aliens but not too advanced to care is just sth. like 3000 years.
And therefore, even if this level of development was reached by two proximate civilizations, e.g. even on neighboring planets in the same solar system -- if those windows didn't overlap, chances for communication happening would essentially be zero.
Given that our planet is younger than most planets in our galaxy, and IIRC younger than the average of all the planets which will be in our galaxy, we are the first if and only if we are the only intelligent life which will ever form in our galaxy.
I'd strongly disagree with the notion of "we are only 14B years into a many-trillion-year stretch" - we're at or past the midpoint, half or more of all the possible potential-life-forming-events in our galaxy have already occurred.
>we're at or past the midpoint, half or more of all the possible potential-life-forming-events in our galaxy have already occurred
Caveat: for life that resembles life on Earth.
Admittedly that's the only kind of life we're certain exists, but more or less alien forms of life seem to be at least theoretically possible. (Which gets into whether we'd even recognize each other as life.)
First one doesn't really make much sense. There are so many intelligent lifeforms on earth (whales, octopods, birds, monkeys, canines) and intelligent hive-minds (bees, ants, termites) that the leap to exponential tool use doesn't seem like something that would take anything close to 100B years, let alone trillions of years.
As for number two, it's hard to comprehend a response that is reasonable because our cognition may be part of the "disturbing reasons" right?
The theory I more and more think is probably right is that there is some major aspect of the universe that we get wrong. What is more likely, humans thinking they understand something when they don't or that no life form was able to spread amongst the stars in billions of years? I have plenty of lived examples of humans with false knowledge.
It's a sort of meta Drake equation. [Likelihood humans are not as wise as they think they are]*[rest of drake equation] and I think the drake equation, as stated, correctly leads to the term "Paradox" given the conventional understanding of science as communicated by scientists.
> First one doesn't really make much sense. There are so many intelligent lifeforms on earth ... that the leap to exponential tool use doesn't seem like something that would take anything close to 100B years, let alone trillions of years.
I don't quite understand your logic here? The big barrier(s) doesn't seem to be tool use, but rather 1) the formation of life itself, and then 2) the move from single-celled organisms to multicellular organisms (this took 2 billion years on earth, so is clearly a very difficult step).
I'm sleepy from a bad night, but let me try to explain:
> our existence now is so unlikely that it's possible that we actually are the first. Something has to be first.
When the OP said that ^ I took we to mean humans with technology, presuming the OP meant that we were somehow special. Basically I took it as him saying that we're first because we're lucky so my argument was:
> How are we lucky? Look at all the other intelligent lifeforms on Earth! Surely the lucky winners would have had some sort of fluke that made them one of the few with intelligent brains on their planet! This could have easily happened sooner on Earth!
If the OP meant that life itself was extraordinarily rare on any given celestial object then that is something I don't consider especially groundbreaking since its part of the Fermi Paradox formula in its basic form the precise value of which has been debated for years and I do not find convincing.
All the intelligent creatures of present earth took at least the 2-4 billion years to come into their existence. The universe 13 billion years old but maybe the early universe was too hostile to allow progress, maybe it required many billion years to have the occasional planet with a wide and useful variety of elements.
"the leap to exponential tool" - the current human leap to exponential resource consumption seems to be colliding with the limited and fragile structure of the earth (IE, CO2 pollution is pushing to catastrophic global warming). A fair number of decision makers seem to expect some tech fix to appear when every indication is it won't. My point is "getting to stars" would require technological progress in a situation where a species learns to curb an appetite for exponential growth, something human beings certainly haven't achieved.
But this is built into the Drake equation to begin with! My other response details out what I was thinking he meant in the first place.
If you want to argue the Drake equation on its own, that is cool, but it wasn't what I thought OP was talking about. My central argument is that if we are first that is pretty unlikely because we have 1000s of intelligent species and for us to be first of many on our own homeworld in addition to being first in the galaxy or beyond is much less likely.
That said, I could see an argument being made for combative intelligences coevolving increased intelligence and this being the counterpoint to my counterpoint. Though I don't buy it.
The problem with the analogy is assuming that humans are the only living things for the ants to find! (An ironically human-centric error in an attempt to expose human-centric thinking) The analogy would be more accurate if the two ants had scanned everything in a one-mile radius and found zero other insects anywhere, which would be... a little curious...
I think 'we're first' is unlikely, but the universe is so unimaginably large that we could well be first in the little bubble we can readily observe. Alternatively, another civilization has come and gone, and we've yet to spot it's remnants.
I don't buy the whole idea of 'we just can't see them'. We're very good at detecting signal from our physical world, and any advanced civilization is going to be noticeable as they start harvesting the power of nearby suns.
Maybe you're right though, maybe 'dark matter' is the mass of other multiverses and gravity is the only force that bleeds through.
3 There is big cost or downside to galaxy-wide expansion that we don't get and that limits expansion, like travelling interstellar distances being far harder than we imagine in practice.
4 We are weird in that we want to expand like this, but others don't, similar to how chimps appear to be well able to express themselves in sign language, but appear to simply lack any urge to do so. Similar to your #2.
5 There simply isn't a compelling reason to expand galaxy-wide by the time you can. Reproduction must be stabilized in some way if mortality is taken out of the equation, which will probably happen earlier, a sufficiently advanced understanding of cosmology and physics might conclude there isn't any danger that can't be managed or that spreading out over a few lightyears wouldn't guard against sufficiently well. Getting rid of evolutionarily helpful urges that become a burden in a post-evolution world might be a filter by itself, so this is similar to your #2 in that they're different in a way we can't easily conceive.
6 Once you can make any existence you want happen (by some kind of unimaginably advanced VR) and have tech keep everyone safe and alive indefinitely, the actual universe might start to seem underwhelming. Better to live out the millennia in a perfectly convincing hedonistic metaverse. I could see that happen to us, come to think of it.
> 3 There is big cost or downside to galaxy-wide expansion that we don't get and that limits expansion, like travelling interstellar distances being far harder than we imagine in practice.
This is my thought. Without FTL travel you have to go the slow way. Probably much less than C thanks to the rocket equation. But in order to do this you need to build a spacecraft capable of surviving for centuries or longer with absolutely no outside support, not even solar power.
But if you can build that you have effectively unlimited space in your own solar system. Why bothering to travel to a different solar system at that point? Maybe if you have used up literally all of the resources in your current solar system, but that's a multi-billion year process. So you might only need to make the trip once or twice in the current age of the universe. But even that seems less likely than just developing really good recycling systems.
So the solution to the Fermi paradox is that by the time you have the tech to travel between solar systems there is no longer any need to do so.
It's kind of like asking why we don't have any driven individuals who do a solo swim from Hammerfest to Port Lockroy. Even with a high tech society the resource requirements are extreme. It is likely to require significant collective effort to build a ship and especially to fuel it. Thousands of metric tons of fuel at a minimum if you want to reach anywhere in only a few lifetimes, probably millions.
Every time you see someone saying Earth is rare in some way, or that the Great Filter is behind us, or that life is plentiful, but far away (grabby aliens being one of those), those are all the same argument, and the exact same argument as your #1.
It is still missing any justification for what is so rare about it. (Not that those arguments are any hard to make; instead the main question here is which of them is the correct one.)
Your argument #2 (that's the exact same as the zoo hypothesis) needs an extremely good reason for no alien at all trying to kill us and take Earth. And we currently lack any good reason.
> "Your argument #2 (that's the exact same as the zoo hypothesis) needs an extremely good reason for no alien at all trying to kill us and take Earth. And we currently lack any good reason."
Maybe life supporting planets are abundant and there's no reason to risk a conflict with us?
We've certainly been detecting a lot of them anyhow.
It could be equivalent to me going to Africa to fight a lion for its den instead of just renting an apartment.
It doesn't matter how plentiful planets are; and it doesn't matter if planets are not the aliens favorite environment. Living beings tend to get at every single place, unless something really compelling is stopping them.
(And we have a large history of killing lions to get their habitat. We do lot of that with ants too, and all kinds of insects like the sibling comment seems to ignore.)
If the Great Filter is behind us, I like mitochondria as a candidate; from what we know of Earth, it took over a billion years to happen, appears to have happened just once, and all complex life has it.
Two billion years, and it seems to be quite the fluke. One kind of single-celled organism ingested another, and instead of killing it or being killed, it provided a support system and in return got more energy back. This was a one-time thing that changed the course of evolution, making multi-cellular life possible.
Question is how often does that occur on other planets with life? Maybe Earth is unusual in that life sticks around for long enough that low probability events happen. Maybe it happened far earlier than it would normally take. The universe is big, low probability events will happen.
My favorite solution is very simple: We're overestimating our ability to detect extraterrestrial live. It might be common and look similar to us. They might even use radio signals. But until somebody demonstrates that you can detect stray telecommunications signals over lightyears I find it hard to believe. I also think it is going to be hard to detect the chemical signature of life e.g. via spectroscopy, if you can't even image the planet next to it's overshining star.
Second, and somewhat sobering part: I also think it is practically impossible to do interstellar journeys. You can imagine scaling up existing tech to do so. But I think at some point the complexity and cost (in terms of resources, not money) would diverge. As an analogy, you can build a small robot, but if you try to scale it up to a mech it will not work in reality. Too heavy to move, yet to flimsy to stand.
Also due to the continuing expansion of the universe, that latter probability will get more infinitesimal for any given pocket of life as time goes on and more & more of what has happens in the universe “escapes” their light-cone.
> 2 - Aliens are everywhere, but we cannot perceive them
We can detect neutrinos with advanced instruments. We've never had an evolutionary reason to do that.
There's really just no room for this explanation. Energy and mass are one and the same. If we can detect neutrinos, but not these intelligent aliens that are everywhere, it means that they don't occupy physical space, don't have mass (and therefore must move at C only), don't use energy, don't send signals to one another, don't accelerate or decelerate, aren't involved in chemical reactions, don't interact with any of the particles we do, don't perceive light, etc. etc. At that point, they basically don't exist in our universe.
It's not enough to say "but ants don't know we exist!" -- first of all, yes they do. Secondly, you're really saying that intelligent ants who formed an advanced society, had a scientific revolution, and built instruments capable of determining the number of moons on Jupiter, still would not know we exist. That is clearly ludicrous.
And this doesn't even solve the Fermi paradox! There's clearly plenty of "room" for aliens that are "somewhat similar" to us; that is, they actually are made of protons and neutrons, etc. Where are all those aliens?
So many incorrect statements and assumptions... our current footprint would be unrecognizable from few hundred light years to even a bit more advanced civilization looking straight at our Sun. So yes there very well may be aliens just like us technology wise say 200 or 2000 or 2000000 light years away and they nor we simply wouldn't know.
We don't know what we don't know from physics, the arrogance of thinking we get it all was there numerous times and it was always a wrong emotion, we even realize it for our current theories. There may be quantum entanglement communication, higher dimensions, strings or basically anything your nor my mind can't even come up with right now. Just like cavemen simply couldn't come up with general relativity even if it was all happening right in front of their eyes.
Imagine if it turns out sentience can arise in stars, gas, dust, or minerals. Maybe they won't be advanced civilizations, more like animals we can't recognize as creatures even when they're in front of us. We might even start mining them, as eyelash mites mine us without comprehending us.
> We can detect neutrinos with advanced instruments...
"We can detect things we were not evolved to detect" is a non-sequitur, a true statement that does not refute the original speculation. Because we can detect some things we were not evolved to perceive, does not mean we can therefore perceive aliens.
It's a difficult concept to communicate. Empirically it's literally meaningless. Even the concept of meaningful vitiates discussion of this idea.
Everything we are is perception, pattern recognition, threat assessment, problem solving. That there might be something important in our environment that we are simply not built to respond to is far easier to reject outright than to consider. This is why it's my favorite resolution to the Fermi Paradox, because it is so challenging to consider.
Our cognition has evolved only slowly compared to our rapid technological advancement. Perception is not simply detection, but also cognition. Though we detect such previous unknowns as neutrinos and invisible electromagnetism and peculiarities of quantum physics, we think about them differently than that with which we are familiar only with expensive and difficult training, and even then it's arguable that we are modeling reality itself or modeling only our limited perception of reality.
In short, while we are impressed with our abilities to understand our reality, we are still constrained by our evolved cognition to think effectively only about living by hunting and gathering in Earth-like conditions.
I also think some version of 2 is overwhelmingly likely.
In particular, I have always found the core premises of SETI surveys profoundly naive in terms of necessary preconditions for it to be meaningful.
"If your only tool is a giant radio telescope, you look for radio signals." And in specific you look in bands that fit various preconditions of your technology; and then you look for signals which are loosely comparable to the ones we humans used nearly a century ago.
The folly of belief that such surveys are likely to uncover unobfuscated communications by some other civilization was truly driven home to me reading here on HN in the last year or two a deep dive into an iPhone exploit that relied on exploiting some issues with its discovery protocols for other devices in the phone's vicinity. The specifics of its multiplexing and frequency hopping and duty cycling across various tasks were hard enough to follow when the priors of the stack and hardware are all very well known.
The only signal SETI is liable to see is the equivalent of someone blowing an air horn in a stadium explicitly to be heard. Maybe someone does that. Maybe they find the forest dark enough to not...
The more interesting survey IMO is to look carefully for Dyson-sphere style dimming...
My favourite resolution is that "intelligence" is a concept created by humans that only humans and species evolutionarily close to humans have. It should be called "human intelligence".
The Fermi paradox doesn't work because we have roughly the same chance of finding a human-intelligent alien as we have to find a Swedish-speaking alien. For all I know the planet Neptune is actually alive and intelligent in a way we cannot comprehend.
> The Fermi paradox doesn't work because we have roughly the same chance of finding a human-intelligent alien as we have to find a Swedish-speaking alien.
1 is not true. You are actually experiencing dartboard paradox. The probability of the dart hitting one particular point is nearly zero. Yet some point has to be hit by the dart.
In the same way, even though someone has to be the first, that does not change the probability of us being the first (which is very unlikely by most estimates of the probability distribution)
I'm not convinced by refutations of #2 that point out that we humans have developed technologies that extend our senses, eg. we can now detect neutrinos, gravity waves, microwaves, what-have-you.
While these are extensions of the senses we have, we still are evolved to understand an environment that is an infinitely narrow slice of all possible environments in the universe, and Earth life's approach is an infinitely narrow slice of all possible ways of perceiving and surviving an underlying reality that is vastly unknowable.
As we look into a Universe (or even look around ourselves here on Earth) with our sense extenders, we are still bound by the limitations of our cognition and perception.
One thing I don't understand about the 'quiet' aliens mentioned in the article - I thought pretty much any lifeform worthy of that name (ie using/converting some form of energy) would necessarily give off some hints of their existence eg through patterns in infrared radiation (don't recall the exact argument). I remember this as a refutation of one possible resolution to Fermi's paradox (what if intelligent species exist but shield their existence from us - apparently the answer is that they couldn't, not completely at least). So in that case, any species (even before reaching any meaningful 'intelligent' phase) would create a bubble of 'noise' expanding at the speed of light.
The word you are looking for is 'technosignature', which is observable phenomenon which can only reasonably be explained by the presence of a technological civilization.
For example, any starship moving between solar systems at a significant percent of the speed of light is going to leave a detectable wake in the interstellar medium. Whatever mechanism is used to propel the starship is also going to radiate heat, which will be easier to detect by orders of magnitude. There is absolutely no natural explanation for little black-body radiators zipping in straight lines between nearby stars at a significant percent of the speed of light.
The most obvious, and clear technosignature is the Dyson sphere. There are hundreds of billions of observable stars in our galaxy alone, and hundreds of billions of galaxies out there, every one of them full of bright stars. All those stars are pretty to look at, but it's the stellar equivalent of a giant oil well fire. All that negative entropy burning away, accomplishing absolutely nothing except for heating the universe by a few pico-Kelvin. It's a goddamn cosmic waste, pissing away the energy reserves necessary to support uncountable numbers of sentient being every second of every day that goes by.
We could capture that light with a Dyson sphere, with technology that we could make in the next 1000 years, conservatively, and quite possibly sooner. In doing so we'd capture the full output of the Sun, getting enough free energy to support hundreds of trillions of human beings throughout the solar system. We could then move through the stellar night, turning every neighboring star system into an abundant garden supporting quintillions of human beings. We could do this even assuming no new technology beyond the things we know how to build right now in the early 21st century.
There's nothing special about us, and a 1,000 years is a cosmic blink in the eye. So if we have this capability since achieving spaceflight, then so would anyone else out there. So where are they? Where are the great swaths of star systems turned infrared by Dyson black body radiation?
Whenever I see the Dyson sphere brought up, I really think people should contemplate the scale of the earth to the sun and imagine where we are getting these resources and mechanical ability to construct this thing. Trillions of meteorites? 100 trillion hours of labor not counting commute time?
The Dyson Sphere can be understood as a metaphor for a civilization harnessing all the potential of its star. There could be other ways to get that much energy or it might not be possible at all. But the Dyson Sphere is the theoretical limit without expanding to other stars.
The bigger question then is why you would need all that energy.
I'm being hyperbolic, but other than being a theoretical model, I was curious as to where the parents' claim of this technology being a "1000 years away, conservatively" came from.
There are various gasses in atmospheres which if measured would be a biological signature. But we aren’t really able to spectrographically measure the atmospheres of exoplanets writ large, nor are biosignatures necessarily a sign of technological civilization.
my understanding was that it would be an electromagnetic signature (ie we could detect infrared radiation from the heat generated as a byproduct of metabolism, or, at least, whatever energy transformations they perform in their technology, once we're talking about technological civilizations). that's what would be near-impossible to conceal (a biosphere might also be a marker, but that might be concealable somehow). and if it's true that metabolism would be detectable, then there couldn't really be such a thing as 'quiet' aliens anyway, that was my question.
For those of you who want to know what's currently going on, here are the names of the main publicly known contactees (people on Earth who publicly report that/how they maintain some form of contact to extra-terrestrials):
- Alex Collier
- Elena Danaan
- Marina Jacobi
- Dr. Michael Salla (no known direct contact, but excellent analyzing/reporting)
You'll want to check out their YT/rumble channels, websites, books (especially Elena Danaan's last 2-3).
I don't understand the relevance. All of the people you mention are the usual nutjobs/UFOlogist/new age scam artists. Nothing to do with the actual search for extraterrestrial intelligence.
My favorite solution to the Fermi Paradox is that star-shaped gravity wells are difficult neighborhoods for anything that needs to exchange huge amounts of data. Think about it: electromagnetic data-beans degrade with distance, so one must use relays. Relays in a gravity well must keep moving in orbits. And, well, stars are noisy and hot. With sufficient technology, a civilization is more interested in reliable data-transmissions and compute, which can be generally easier to achieve in interstellar space (which also happens to have enough "cold" matter in the form of wandering planets and planetoids).
There can be a huge number of civilizations gravitating around a star, just as we do. But any bigger civilization, bigger than their mother star, may soon find the interstellar space more comfy and remain there, beaming directional messages (and consciousness units, a.k.a souls) between cold outposts in interstellar space.
Yeah, asking those questions is inevitable but what answer would a Newton give back in the day if asked how to go to the moon? It's our turn now and anything would go, from fusion to antimatter, from dark matter to dark energy. Vacuum energy, I'm sure there is at least a scifi story about it as energy source.
Edit: that was easy, the Zero Point Module in Stargate SG9
Fusion, probably. They have to find enough fuel in interstellar space, but theoretically it's possible.
The bigger question is why you would want to exist in an entirely artificial environment far from any star, even if it makes information interchange and computation more efficient.
You can have artificial habitats which are almost in any way better than a planet. Even bigger, by a few orders of magnitude, if that's your metric. Maybe that's not something that will be readily available to you during your first millennia in space, but we are talking about larger timescales.
The bigger question is if something that old will want to be bare-organic (as in running in actual wetware), or "virtualized". If the former, bigger, fancy habitats will be wanted. If the later, big and efficient datacenters will be more important. If they are as "we-want-morrrrrrr-choice" as we are, they are going to want a mixture of both.
I have to say, I never understood the huge emphasis on colonizing worlds outside our solar system. My pet theory is that by the time we are capable of such a thing (and thus, capable of making spaceships that can sustain human life for the duration of the trip), I'd argue we've become a space native species who are very much used to living our lives on ships. I'm not saying colonization wouldn't happen, but it'd be the thrill seekers looking for something new.
I think it would be driven by curiosity, but once you colonize another star system, it's a fully fledged civilization without meaningful contact to the mother system. Including to visit the next star system.
It's also quite easy to space travel outside of gravity well. Just take any piece of ice, drill yourself inside it and use thick ice walls as shelter. Mount some engines. If you're used to living in such environment you can be having a normal life while going around in it. Fusion as power source, likely.
Earth civilization is wondering why it can't see or hear anyone while almost literally living inside a beacon.
There's an even simpler one: if you leave your stellar neighbourhood, you're creating unreachable isolated islands, not "galactic empires".
The whole notion of "expansion" is such a weird 19th century concept that just doesn't seem to go away. Space isn't the Earth, other star systems aren't unexplored continents or islands in the ocean - they're islands in spacetime.
I've yet to be presented with a rational explanation as to how any civilisation would be able to a) stay stable in terms of biology, culture and technology over geological time scales and b) have any means of expanding itself over distances that make communication practically useless (e.g. even at "just" 25 light year distance, two-way communication would take 50 years) and c) are somehow advanced enough for interstellar travel and presumably efficient terraforming or genetic modification yet unable to control population growth and resource utilisation...
Since we haven't discovered everything there is to know about physics it is still rational to propose that control of the gravitational force is possible given some further discovery. This could lead to faster than light travel which negates the list of barriers you've given.
FTL would defeat causality and even "just" controlling gravity would be basically equivalent to god-like powers (it would mean assuming direct control over spacetime itself). Controlling gravity would negate the need for colonisation entirely - it would provide basically limitless power plus full control over your host star's lifetime.
Aside from that, almost all papers on the topic including this one focus on subluminal space travel.
Sure, once you incorporate technology that goes beyond your current understanding of the universe, many counterpoints go out the window, but this level of technology only serves as an argument against the need for expansion in the first place (with the exception of "because they can").
FTL would be fantastic for research and science expeditions, but expansion into random nearby star systems would be even more pointless, since such civilisation would be able to pick exact/close to exact matches to their home world as candidates for settlement. Such worlds could then be thousands of lightyears apart, as neither communication nor travel would pose a problem. This would also easily explain the lack of (radio-) signals, as exchanging information would be carried out via FTL travel, not radio waves. Why would a civilisation capable of FTL choose to go through the trouble of terraforming or building megastructures around random stars? Wouldn't they rather choose to harness the power of black holes then? A planetary mass BH could power a civilisation for trillions of years for example.
Yes, I agree with all of that. What you've said pretty much aligns with my view on the Fermi paradox which is that we live in a post scarcity universe where 100% of alien civilizations discover FTL technology and have no need for EM transmission or the kind of spreading colonization that the grabby aliens paper talks about.
There's something I intuitively dislike about the early human hypothesis to the Fermi paradox. It seems too much like geocentric Earth hypothesis or the long line of hypotheses which suggest us humans are special in some way. We rarely are.
I find the Fermi paradox fascinating though because non of the proposed answers satisfy me. These days I tend to think it's likely there are few compounding factors instead of any one single factor. I quite like the idea that intelligent life probably is fairly rare (so maybe we are quite early) and that the intelligent life that does evolve is fairly likely to either destroy itself or to simply lose interest in the analogue world with time. Personally I think if there is intelligent life out there most of it is probably living in digital worlds because why use energy exploring and explaining this universe when you can just create your own?
On the less likely but interesting side of things I also wonder if it suggests simulation sometimes. If everything points to us being quite uncommon then at some point it becomes reasonable to ask if it's even a question of probability but instead perhaps one of intention. If you see 10 dice on a table and all are showing a 6 on the face, you probably wouldn't think, "oh, how unlikely", but instead assume it was intended. But then again simulation theory is a good answer to all hard questions so I'm not that keen on it either. I just think it's most compelling in the context of the Fermi paradox and our seemingly fine-tuned universe.
I believe that the earth centric and human centric view is the problem with the Fermi paradox. Why do we assume that a civilization more advanced than us would have desires towards colonization and contact with lesser lifeforms?
It would be like an ant colony assuming there are no more advanced lifeforms because a more advanced lifeform would have destroyed their colony or contacted them via pheromones
With the "grabby aliens" there is only the assumption that a portion of civilizations become grabby. We don't have good reasons to believe that portion to be zero. But even a very small chance leads to all the other predictions, like that we are early and so on.
It's also not so much about active contact than that you could observe technological signatures from a certain distance.
Our definition of "technological signatures" is an ant colony's pheromones. Because we don't have a solution to quantum gravity we cannot rule out the possibility that other civilizations can control space/time without emitting photons.
Our civilization is already putting out photons into the neighborhood. Hard to imagine other civilizations being able to master that technology in a blink of an eye when it's not even possible with all the physics we know.
I don't like ant colony analogies because I think there is a meaningful difference between a life-form entirely unable to communicate high-level abstract thoughts and those that are - even if it's relatively simple.
For example we view apes as "lesser lifeforms" to ourselves but we still try to communicate with them, and they communicate back to some degree. Or a more extreme example would be dogs - we communicate with them all the time even if they don't have anything that interesting to say back to us.
I'd also argue we still take significant interest in ants despite the fact they're unaware of us. And if we thought we could say hi to ants via pheromones we almost certainly would. The mere fact we keep records of all the species we find on Earth and try to understand them in great detail despite them being much less intelligent then ourselves I think suggests aliens would probably at least have some interest in us, even if we're not that interesting.
And even with ants it's clear we have a lot to learn from them. Ant colony optimisation algorithms wouldn't exist if we didn't take an interest in ants, for example.
I don't think the fermi paradox assumes that. Aliens don't have to want to be seen for us to see them. All it takes is one civilization failing to hide for us to see aliens, so the question then is "why has every single intelligent life form dedicated so many resources toward effectively hiding" or "if they're not doing that why haven't we seen them"
From Wikipedia: "Even at the slow pace of currently envisioned interstellar travel, the Milky Way galaxy could be completely traversed in a few million years.[12]"
The assumption is that they would be expanding to larger areas of the galaxy that they have not been to before. I'm asking why we would assume that they would want to expand to billions of solar systems. Obviously we can assume that humans would want to expand since we have a long history of that. But there is no reason to assume they would think like humans, especially given that we have not achieved interstellar travel ourselves.
The beautiful thing about grabby aliens is that it only takes one grabby civilization for the theory to be true. It’s not assuming that there are tons of civilizations that act like that, it’s saying that if there is even one then we won’t see them until they conquer us.
Unless that grabby civilization encounters a much more advanced passive civilization. And that passive civilization decides that the grabby one is a virus that needs to be eradicated.
In both a universe with few "grabby" civilizations, and a universe with many non-grabby civilizations there would be countless lifeforms, just more or less diversely distributed among civilizations. In either of these universes us here being as early as we are is equally "suspect".
Should I assume humans will soon achieve immortality and stop breeding (or just go extinct) just because it makes me less of an outlier? Cause that seems to lead to the exact opposite conclusions, just by putting the delineation point at an individual rather than a civilization.
"Furthermore, we should believe that loud aliens exist, as that’s our most robust explanation for why humans have appeared so early in the history of the universe."
The most robust explanation for humans appearing so early is that yeah, it seems we did appear early, someone had to - since it doesn't assume an entire model of intergalactic civilizations.
Space is really big, and radio emissions are really weak. The strongest isotropic radio emissions from Earth (e.g. high power TV broadcasts) would be indistinguishable from background radiation at only a light year or two away. One study [0] suggests that directed radio emissions an order of magnitude more powerful than the most powerful radio emitters on Earth could be detectable at ~100 light years (1/1000 the diameter of the Milky Way), but our detector would have to be perfectly aligned with the transmission at the exact time it reaches Earth.
This still doesn't explain why we don't see evidence of life though, just why finding evidence of alien life via eavesdropping on extra-terrestrial radio emissions would be unlikely.
If the galaxy really was full of intelligent life it's likely we would see evidence of it in some form. For one, it seems probable that any expansionist intelligent life in our galaxy would eventually notice our Earth is likely to be an interesting place. Even if they didn't visit us personally it seems strange they wouldn't send a simple probe or try to make their presence known to us in one way or another.
But to your point, perhaps intelligent life is quite common, it's just rare for it to be expansionist - at least beyond it's own solar system. In which case yeah, there could be a lot of Earth-like civilisations out there, but we'd be unlikely to see evidence for them.
This is brought up a lot, and while there is likely some truth to it - with plenty of fun examples in science fiction - it seems to me there is a strong counterpoint in that the mechanics of physics, biology and even civilization have many mathematically predictable properties. The environments capable of supporting life will nearly all likely have certain similar features which shape how that life behaves. Finite resources are one of the better examples.
It has always been interesting to me how there are several prominent instances of architectural feats or scientific/technological breakthroughs which arose independently from people groups who had no contact with each other. I don't think extrapolating this to potential life in other star systems is too much of a stretch-- and there are certain behavioral traits you can reasonably expect in such scenarios, like large scale cooperation.
Some of the most capable & best equipped minds we know of, when faced with how to communicate with intelligent extraterrestrial life, decided that math and basic physics were the best initial overtures. From those basics (along with the assumption that someone eventually perceives them) I believe a great deal more about such life can be probabilistically inferred.
Sending a probe takes very, very long, and is just as expensive, so it seems even less likely to arrive than a radio signal. And we might not even notice either one if it gets here.
Interstellar meetings are bound to happen first with a large developmental gap.
Applicable here is obviously us being the Cavedwellers, Sumerians, Azteks, Egyptians, whathaveyou.
What happens? Astronauts appear as effectively gods, being literally superior beyond comprehension in every aspect. Religions sprout, sacrifices are made, wars fought...all because you thoughtlessly wanted to be nice and sey 'hello'.
Self-knowledge is a prerequisite to fruitful, non-destructive communication between civilizations. The ability to comprehend the scientific technicalities is likewise necessary and we are just on the brink of that.
There are (many) other requirements. Importantly, you have to be able to imagine a superior entity other than as playing the role of your "master".
> This still doesn't explain why we don't see evidence of life though...
It is an adequately plausible explanation of why we haven't yet seen evidence of life elsewhere. To argue against it seems to require one or more question-begging premises.
Such as intelligent life having billions of years to send probes, build powerful radio beacons, and form galactic civilizations? It is called the Fermi Paradox because the physicists did some basic calculations at how long it would take to colonize the galaxy.
So we have two sets of calculations: the ones you are referring to here, and those that MontyCarloHall brought up. Of this pair, only the latter predicts the observation that kypro brought up.
Could we feasibly send one? Yes. Could we feasibly get data back from it? Less certain. It would necessarily be a multi-generational project in either case.
I mean we physically could send a probe... We effectively have, with "VGER". At some point, the voyager probes will hit another star system, it's just going to be a very very long time.
If we actually wanted to aim a probe at another star system, I think that's probably within our technical grasp, but again we don't have any real way to get there in a reasonable timescale, or send data back once we're there. Not much use sending a probe 4 light years if the transmitter isn't powerful enough to send a signal back, and a transmitter that powerful would probably be too large to fit on a probe we could currently launch.
Perhaps lasers could be used, but you'd still need a fairly powerful one, and then you have to worry about interstellar absorption of the signal if you go through a dust "cloud". I guess with a laser you're also really pinpointing where you're sending information to, if you care about that.
There's a growing body of evidence that Earth has already been visited numerous times by something other than humans.
Certain classes of UAPs demonstrate flight characteristics that are not possible given our current understanding of gravity and aerodynamics.
Dozens of credible eye witnesses from multiple countries; fighter pilots, commercial pilots, nuclear physicists, and high ranking government officials.
Source "In Plain Sight", US Navy fighter pilots David Fravor and Ryan Graves, etc.
People are quick to dismiss these stories as hoaxes or bad memory, but scientific discovery almost always starts with an unusual or unexplained observation.
Uranium was discovered in 1785 and ionizing radiation wasn't discovered for another 110 years in 1895. True scientific understanding of new observations takes quite a while.
Those aliens would bring own bacteria that could kill a lot of things if not everyrhing on Earth.
Somehow people have this "star trek" thinking, that hypothetical unknown microbes from other planet wont eat you alive, because you are somehow immune to them.
A species which has mastered inter-stellar travel and tractor beams (/s) probably has some higher control over their own biology and sanitation practices.
I've never understood why alien bacteria are a perceived threat. Viruses and bacteria share the same genetic material as we do, and literally evolved to infect organisms of that ilk. I have always supposed that alien viruses would just be inert, and alien bacteria would rapidly die off in the inhospitable environment of an earth-organism's body.
> There's a growing body of evidence that Earth has already been visited numerous times by something other than humans.
>Certain classes of UAPs demonstrate flight characteristics that are not possible given our current understanding of gravity and aerodynamics.
Correction: there's a growing body of evidence of things that look like they're demonstrating "characteristics that are not possible given our current understanding of gravity and aerodynamics". It's a leap to conclude there are actual objects that are violating our understanding of gravity and aerodynamics. The fact that these observations are always in the context of grainy/ambiguous videos should cast some doubt on whether they belong to "something other than humans" or are just optical illusions/artifacts.
>Dozens of credible eye witnesses from multiple countries; fighter pilots, commercial pilots, nuclear physicists, and high ranking government officials.
The credentials you specified are only good insofar as to ensure they're not making shit up, but it does nothing to address concerns that they're looking at optical illusions/artifacts.
The credence given to UAPs on HN after recent declassified reports is puzzling. Ufology is a very cool field, but it's astounding to see people shape their worldviews based on such scanty "evidence." And who's to say that the whole thing isn't just a massive disinformation psyop?
We noticed GRB221009A despite it being 2.4billion light years away. Makes you wonder if someone took the opportunity to encode data in it.
Edit: Another reason to analyze it is that existential threats are a universal language. Any sufficiently advanced civilization must pay attention to possible threats, so that it can avert them. It then follows that if you want to get the attention of another civilization about which you know almost nothing, threatening them is a viable method. Of course you don't want to overdo it, lest they actually hunt you down. A blast of high energy (but non-lethal) radiation will draw attention without making anyone panic. Intelligent civilization within a huge radius will certainly be tuning in.
The Fermi Paradox seems to rely on other civilised aliens being detectable. But why would they be? Unless they're emitting a LOT of radio waves (and we've switched mostly to streaming not broadcast) OR doing some giga engineering, what would we see that we're currently not seeing?
Maybe in 50 years, assuming we have the telescopes to look for cities on extra-solar planets, we will find them everywhere. But right now, the absence of either high powered radio or Dyson spheres does not mean the absence of civilisation.
As for the argument I find it very convincing, it seems the best answer to the Fermi Paradox, much like the anthropic principle is to the obverse problem of the universe being very hospitable to life. None of the comments here address any serious issues with the argument.
The uninteresting solution is that when we compare humans to tapeworms - there is such a complexity gap that no amount of technology will ever enable a human to have "a meaningful conversation" with a tapeworm... That one can only logically assume there are beings to which we in turn are "tapeworm complexity" (also a thought: maybe we all live right now in such a higher being?) and hence will never be able to perceive them for what they are.
The more interesting space (sorry) is "at a level comprehensible to us" - to which I'd say "space is vast and the universe is young". I highly doubt our presence is at all visible even from the closest star system.
> That one can only logically assume there are beings to which we in turn are "tapeworm complexity" (also a thought: maybe we all live right now in such a higher being?) and hence will never be able to perceive them for what they are.
Indeed. Does an ant know that it exists as part of a larger organism? Perhaps we are part of a larger organism, at which scale, our individual human lives are of tapeworm complexity.
I don't think so. It seems at this point that humans can understand most of the fundamental laws governing our universe, and perhaps to harness them to eventually have star system-level impact.
I'm not sure how much smarter are you really going to be. Especially given the social nature of humans which makes us able to compensate for each other's shortcomings.
I'm of the belief that understanding is only ever "less wrong", and can only be asymptotic to "total knowledge". Thus current "understand most" is really (and ever going to be) "understand very very little" - there's always infinitely more to be less wrong about; Also as an example: electricity - our brains wouldn't work without it, yet it took us very long to understand the principles enough to be able to do anything useful with electricity; What about consciousness - we can't even seem to agree on a single definition much less "understand it" - perhaps we're still missing something as "big" and as much "part of us" as electricity?
This is not about being smarter as it is about fundamentally different orders of magnitude of complexity. Getting a whole swimming pool full of tapeworms will not make them any more human - and in the same sense a whole planet of humans won't make them any closer to more complex beings (whatever they may be).
As I said, this solution is uninteresting because by definition bacteria/tapeworms/humans can't comprehend "up". And yes, evolution, understanding of the universe and technology may as well bring us to the point when _they_ understand - but by that point, to us now, _they_ won't be human (`bacteria < tapeworms < humans now < next_order_beings`).
Well, humans can comprehend "up", you're doing it just now. And that's why I think there is no "up". As soon as you get to turing machines, it's just more turing machines all the way up.
I did some thinking on the Fermi paradox some time ago. I arrived at the following theory(I am probably not the first one), using these assumptions:
- speed of light(causality) cannot be practically broken / cheated
- current stasis technology theorizing is over-optimistic
- brain-computer interfaces are possible
- computational power/speed will continue to increase
I am assuming that some time in the future, a human will be able to process information 1000x faster than one is able to today, using brain augmentations anr/or brain-computer chip interfaces. This does effectively slow down our perception of time by a factor of 1000x (simplifying and ignoring inefficiencies of course). So if I lived in that time, and got diagnosed with a terminal disease and 1 year to live, I would spend my last year in VR, perceiving it as 1000 years.
Continuing that thought, I might spend my entire life inside VR, living a thousand lifetimes before my biological body gives in.
The galaxy might be full of life, but at a certain point in their development, they turn inwards, because it gives much bigger rewards (the first instinct of any life form is to survive for as long as possible).
The biggest flaw I find in my theory is the assumption they couldn't just VR on spaceships while they're exploring the galaxy anyway.
Brain computer interfaces could be 1000 times faster than skin/eye/ear to brain but the speed of the brain is going to stay the same, right? No accelerated time, at least not much of it. Example: if you accelerate audio 1000 times you won't be able to understand it. Two times? OK, with some training. 1000 times faster video? It's a blur. 10 times? Maybe. Your reaction times to give inputs? The usual tens or hundreds of seconds.
The biggest flaw in this and similar theories is that it requires 100.000000000...% of beings to decide this is the way to go. Not a single being or entity (corporation, or something more exotic) ever decides, over the whole life time of the civilization that, hey, if we send a space ship over there we can have an entire solar system of our own to play with. Including possibly entities constructed for the explicit purpose of doing that by other entities who do not themselves care. One must also consider that not every being is necessarily limited by our life span too; star travel is effectively impossible for us in our state, but if we casually lived 10 million years and could propagate that in space ships star travel would merely be a massive inconvenience. Plus civilizations can in principle live in denser areas.
This is a general problem across most kneejerk answers, like "humans just suck so hard that there's no chance that they'll make it out before they kill themselves". Possibly true. But to be an answer to the Fermi paradox, it must be the case that all civilizations have that problem, including ones based on insects with strong hierarchies and ones based on super-hippies and slower ones and faster ones and all the ones.
It isn't enough to explain 99% of the problem away, especially if it's done with explanations that aren't even necessarily that good in the first place. You need 100.00%, with several significant digits. (I used more in my first paragraph because that was per being, this one is per civilization.)
I think you can safely leave it at 99% or so if you assume a maximum "radius of effect" that a civilization could have over X billion years. If the limit of a civilization is, for example, on the order if 100 light years, then there could be several such civilizations in our galaxy without us noticing it.
I have a tangential thought similar regarding simulation theory, that perhaps there is no other aliens because we're the only one 'simulated', and the purpose of said simulation is because in order to train AI (we're already seeing this) an AI needs a physical body, of course a simulated physical body could probably suffice, it needs to be nurtured by a parent, and experience the world with all it's senses/sensors.
Perhaps we're just ai-babies, and when we're done here we move on to being ai-butlers to rich people in the 'real' world.
If we're a simulation then there's no reason why alien life couldn't also be simulated unless there's a specific point to our simulation that the presence of alien life would interfere with. If there's a point to the simulation we're all experiencing I have no fucking clue what it is.
This happens everywhere in the universe, so the basic process to cause organization is everywhere. We observe this in stars, galaxies, etc. We can then also hypothesize that if organization is everywhere, so are the "organic molecules" such as those found in nebulae or on asteroids. We also know that "organization begets organization" via self-replication: "vortices in turbulent fluids spontaneously replicate themselves by drawing energy from shear in the surrounding fluid". (quote from the 2014 article linked above)
This is such a fascinating subject that I get so much joy from studying! It seems like such a moot question about whether there is life elsewhere because we're neck deep in the stuff!
This doesn't provide any answers to the Fermi paradox, to be sure, but I think it does provide a very solid foundation upon which you can say "life is everywhere".
You know, I'm not entirely sure! I'll remove it if I'm still able to.
oh wait, I think I had a half-formed thought about how some folks get confused with the chemical definition of organic vs the colloquial definition. i.e. a chemist will define it as something that has carbon-hydrogen bonds, but a layperson will say it's something that is part of a living thing.
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[ 3.3 ms ] story [ 270 ms ] threadThe authors supposedly have, and I’m no expert, but I don’t find the argument completely ridiculous. The universe isn’t that old compared to its size; I think it’s plausible for two unlikely events to have happened without their causal cones having intersected yet.
Obviously it's not a guarantee, but I believe it is a viable theory as to why the world described in the article may be possible.
That's mostly true but also not quite.
The longest-lived main sequence star will have a lifetime of about 500 billion years, the shortest just a million.
The only stars that are likely to live into the trillions are red dwarves, which are very common but which have very small habitable zones due to their feeble output.
> "Advanced aliens really are out there, and we have enough data to say roughly where they are in space and time, and when we will see or meet them."
is not proven. It's just some really smart people attempting to reach a conclusion I'm not sure is within reach. We just don't know.
1. Life can evolve into us. Therefore life on other planets has p>0 to evolve agglomerations of matter we would call "alien civilization"
2. Evolution seems to be driven through external constraints, and seems to generate similar structures to solve similar problems. Hence it's not insane to postulate organelles and their function are a particular energy minima to a complex set of constraints - ie. evolution on any earth like planet might reach similar patterns as earth life.
3. Neurological function seems to be driven by laws of mathematical dynamics up to a point - if it's math, we will see it everywhere in the universe. What sort of math - I suppose nobody completely understands yet.
4. I use the above to postulate that familiar modes of existence and familiar neurological function can emerge anywhere in the universe
5. If a species is to survive, it needs to have innate drive to do so. Unless species innate drive to survive perishes, an intelligent species will realize it's chances of survival are better if it is not limited to one planet. Then, one solar system and so on. Therefore we can postulate a "natural tendency" to start interstellar expansion.
6. Humans have already launched an interstellar space craft (Voyager). Therefore p>0 that life can evolve to develop vehicles that exceeds the escape velocity form their home star
Or something like that. The thing is, I don't understand the problem well enough to know if it's impossible to probe by statistics or not. I just know I'm not smart enough to solve the matter - when I did a course on Bayesian statistics the thing that left me astounded time and again was that one could create sane and accurate models from incredibly thin amount of data if one just had a good enough grasp of some of the factors at play.
It's worth pointing out, that's not how natural selection works. NS would be: If a species has an innate drive to survive, it will do so. Yes, subtle. But essential.
That aside, how would you account for an asteroid strike?
https://en.wikipedia.org/wiki/Fermi_paradox#Drake_equation
That however circles back to space being large. While a galaxy might host hundreds of civilizations just like ours at any given time, the distances between them can be insurmountable. Time is also pretty large so even a civilization that survives thousands or even millions of years might never overlap with another that they can contact.
It pre-supposes you can event build a bunch of invincible perfectly programmed micro/nanobots in the first place. Then you can identify a target body in a solar system a long ways away. Then predict that system's position with an accuracy your probe could land on it after a trip of hundreds of light years (or launch a probe with a bunch of fuel to do terminal maneuvering). Then those probes would function after millennia of dormancy.
It's all possible. But the concept shouldn't be treated as inevitable.
It also runs right up against panspermia theories. What's the practical difference between a single celled organism and a self-replicating nanobot?
Really it's just one example of a technosignature that is longer-lasting than radio waves, that extends the amount of detectable overlap we might expect to have with an older civilization, and the lack of observation either says that sort of technology is either not feasible or there aren't many civilizations in the galactic past or present.
Some care should be taken to see that this principle is not being used to excuse just making things up. Bayesian statistics is rational but not magical, and it cannot create information out of nothing.
In practice, this comes down to the question of whether the model is plausible, accurate, complete and constrained enough to deliver an answer that is informative about the external world, as opposed to the choices made in modeling. Something more than reasons to believe various probabilities are non-zero is needed.
I feel that, in your final paragraph, you are grappling with this issue.
> 1. Life can evolve into us. Therefore life on other planets has p>0 to evolve agglomerations of matter we would call "alien civilization"
In any universe that we can observe, we must exist. That strips away any useful a priori probability estimations about how likely we were to come into existence. p ~= 0 is still p > 0. There could have been a trillion trillion trillion trillion universes before this one where no life evolved that we would never know about because we were not around to observe them. And there could be a trillion trillion trillion universes after this one in which no life arises.
Of course there are quite a few steps from suitable RNA synthesis mechanism emerging to LUCA.
But until we get CERN level investment into research on abiognenesis I don't think the matter can be considered impossible to solve.
The outcome might very well be that chance of life emerging is close to zero (I don't believe it, but it's just a belief, nothing more). At this point we can only conclusively say more research is needed.
If someone is in the field I would love to hear recent details.
The expansion model seems to work though.
I always wondered if this was due to a badly implemented stochastic model. Since if the average goals per game was lets 5 and the score was 2:2 the likelihood of another goal would increase in the last minutes.
This is how this argument feels as well.
So first they say we are unlikely early. But if you consider that we are special (“grabby”) then that’s ok. Somehow like saying there would be another US like country in Europe if the Mayans were developing faster.
I don't think that's their reasoning. I think they say:
1. once grabby civilization appear - it decreases likelihood of other civilizations appearing
2. so actually weighting by probability we're not early - we're average, because the probability of appearing late is almost 0
This kind of backward probabilistic reasoning always felt like cheating to me, especially when it's not only used to validate our models but to create them.
As for NHL I don't know, but in football (soccer) 75% of goals are scored in first and last 5 minutes of both halves, and the single most likely period to score goals in is the final 5 minutes of the last half. So it was maybe realistic :)
Re the article: yes, I understand their reasoning. But isn’t it like saying: if we were to become a greedy civilization THEN in the future we would think how good that we were early…
- Life has to go through "hard steps" to get to civilization
- (I really hate this one at a personal level for multiple reasons) assuming alien civilizations will use Dyson spheres
- There exists some sort of 'great filter' that prevents civilizations from expanding
For each of these, we have absolutely no data to compare to in order to support or refute these statesments.
Saying "if the drake equation holds up, then why is it so quiet in the universe?"
As soon as we have one data point from another civilization, the paradox automatically disappears. It's only in the absence that we can ask the question, and speculate.
Life is hard. We know that because it took billions of years from the first self-replicating molecules to us. We also know there are things happening in our solar system that wiped us out. We know we could have wiped our species out ourselves.
The "great filter" is one theory to explain why on the one hand we should be observing other civilizations, but we don't. Also they don't need to use Dyson Spheres exactly. But before they start expanding in earnest, they would have a measurable effect on the emissions coming from their star, as perceived from other stars.
[1] I do not think that the simplifications are problematic, as long as one is aware of them. It is rather the opposite: Running a simulation with a simplified model helps us to observe some basic principles at work. Later we might refine and enrich our models and simulations. To use an analogy: If we want to study the movement of objects under the influence of the Earth's gravity, we should start with cannonballs and not with feathers.
For over a billion years Earth has been broadcasting a very powerful signal screaming "likely biosphere here" in the form of its albedo spectrum. It's a wet, warm planet that for almost two billion years has had a heavily oxidizing atmosphere. There are few natural explanations for that that don't involve life, since it strongly implies that something is doing work to maintain an energy differential.
If there are "reaper" aliens around in any form, it would be logical for them to start firing relativistic kinetic weapons at any candidate biosphere immediately. Why wait for intelligence to even get a foothold? Just whack any potential competitor while it's nothing but goop and creepy crawlies.
So if there are ancient powerful hostile or "grabby" aliens around, we should not be here.
It's a pretty powerful argument for one of:
(1) We are very early.
(2) Intelligent complex life is extremely rare, occurring less often than e.g. once per galaxy per ten billion years. (A bit different from being very early since it implies we might never find another even after billions of years.)
(3) Something weird is going on, e.g. our solar system is being kept as a wildlife preserve and/or there is a "prime directive" or something.
(4) Something even weirder is going on, which explodes into a long tail of possibilities. Maybe we are wrong about our basic cosmology. Maybe continued advancement in intelligence leads places very different from space flight such as traversing dimensions or converting oneself into some more exotic form invisible to us (like the "ascension" trope in sci-fi). ... and so on.
It reminds me of people who hate the idea that a omnipotent being created us, but are fascinated by the idea a hyperintelligent being simulated us
Also, if you want to discuss what God is or wants of us, pick a God and we can discuss, based on holy books and revelations, what His/Her/its intentions may be. Just saying "God" doesn't mean anything at all - there is little similarity to be found for example between YHWH, Brahman, and Amaterasu that could see a meaningful discussion.
In particular, speculating about what God may want (even if you believe one exists) is entirely futile, as it could want anything at all. In contrast, there are constraints on what an alien species could possibly be like - for example, we know with essentially absolute certainty that an alien species wouldn't eat quarks, whereas there is no reason to say that God wouldn't consume quarks.
Now of course, depending on your particular religion, you may have some things that you believe God told you explicitly. In no major religion though is God just lonely.
For example, in Christianity God created us and He only wants us to follow His laws; the notion that we could evolve to become akin to God is heretical - God is only one, and He demands worship and love, not emulation. For another example, in some versions of Hinduism, God (Brahman) encompasses everything, and we are already God - we can grow to understand this thing, but the very notion of a second God is entirely nonsensical, as God is already literally everything.
From the Book of Abraham (an LDS scriptural text):
21 I dwell in the midst of them all; I now, therefore, have come down unto thee to declare unto thee the works which my hands have made, wherein my wisdom excelleth them all, for I rule in the heavens above, and in the earth beneath, in all wisdom and prudence, over all the intelligences thine eyes have seen from the beginning; I came down in the beginning in the midst of all the intelligences thou hast seen.
22 Now the Lord had shown unto me, Abraham, the intelligences that were organized before the world was; and among all these there were many of the noble and great ones;
23 And God saw these souls that they were good, and he stood in the midst of them, and he said: These I will make my rulers; for he stood among those that were spirits, and he saw that they were good; and he said unto me: Abraham, thou art one of them; thou wast chosen before thou wast born.
24 And there stood aone among them that was like unto God, and he said unto those who were with him: We will go down, for there is space there, and we will take of these materials, and we will make an earth whereon these may dwell;
25 And we will aprove them herewith, to see if they will do all things whatsoever the Lord their God shall command them;
26 And they who akeep their first estate shall be added upon; and they who keep not their first estate shall not have glory in the same kingdom with those who keep their first estate; and they who keep their second estate shall have dglory added upon their heads for ever and ever.
The founder of the religion spoke at a funeral and had this to say:
The mind of man is as immortal as God himself. I know that my testimony is true; hence, when I talk to these mourners, what have they lost? Their friends and relatives are separated from their bodies for only a short season; their spirits existed coequal with God, and they now exist in a place where they converse together, the same as we do on the earth. Is it logic to say that a spirit is immortal and yet has a beginning? Because if a spirit has a beginning, it will have an end.
That is good logic. I want to reason further on the spirit of man, for I am dwelling on the spirit and body of man--on the subject of the dead. I take my ring from my finger and liken it unto the mind of man, the immortal spirit, because it has no beginning. Suppose I cut it in two; as the Lord lives, because it has a beginning, it would have an end.
All the fools and learned and wise men from the beginning of creation who say that man had a beginning prove that he must have an end. If that were so, the doctrine of annihilation would be true. But if I am right, I might with boldness proclaim from the house tops that God never did have power to create the spirit of man at all. God himself could not create himself. Intelligence exists upon a self-existent principle; it is a spirit from age to age, and there is no creation about it. Moreover, all the spirits that God ever sent into the world are susceptible to enlargement.
The first principles of man are self-existent with God. God found himself in the midst of spirits and glory, and because he was greater, he saw proper to institute laws whereby the rest could have the privilege of advancing like himself--that they might have one glory upon another and all the knowledge, power, and glory necessary to save the world of spirits.
http://mldb.byu.edu/follett.htm
Is that accurate? Clarke's third law and all that. Any discussion on what alien beings, or for that matter, some sort of hyper-advanced AI intelligence, ends up unbounded by the limitations of current human knowledge. People ascribe omnipotence and omniscience to such hypothetical entities all of the time, but also anthropocentric motivations.
See Roko's Basilisk which presupposes a future superintelligent A.I. is able to project back into history with perfect clarity, create simulations of sentient beings, and is petty enough to exact vengeance upon them. So you end up arguing about secular deities.
These discussions are fun yet wrapped up in non-falsifiability and woo.
It is - we would have to be so wrong about how the universe works for that to be possible that it would be absolutely miraculous that we can even make a fire, not to mention a particle accelerator.
People tend to significantly underestimate how little room there is for us to be significantly wrong about such things and still have all the observations we've made. There are still major gaps in our understanding of the universe, to be sure, but they are nowhere near the level of allowing for beings which strip quarks from a nucleus.
What is the bias here? Who is biased, the "reaper" aliens? The commenter you are responding to? Can you expand your comment a bit?
> We only started sending out low entropy information out into outer space in the past 120 years or so
Humans yes. But our planet looks unmistakably like it can have life. That is the signal.
I think a more practical take on this isn't life is rare it's that both space and time are big. Two civilizations existing simultaneously but 1/100th a galaxy apart are still a thousand light years apart. Each would see the other's home system as one of billions of observation candidates.
Even with massive SETI operations by both civilizations the odds of those two civilizations discovering one another are pretty small. Even if we posit advanced civilizations are more abundant, separated by only a few hundred light years, the odds are still very small any two civilizations will find each other.
Detecting "leaked" radio emissions just isn't a thing that can happen. The inverse square law make this plain. If we placed our most sensitive radio telescopes on a planet in the Alpha Centauri system we wouldn't be able to detect Earth's radio emissions save for rare blips where a powerful radar system's beam happened to point directly at Alpha Centauri. Earth would need a system of persistent ASETI transmitters aimed at specific stars to have a chance to have emissions be detected by civilizations there.
There don't need to really posit anything weirder than space is fucking huge to explain the Fermi paradox.
1 - Given that we are only 14B years into a many-trillion-year stretch, our existence now is so unlikely that it's possible that we actually are the first. Something has to be first.
2 - Aliens are everywhere, but we cannot perceive them for reasons we would find disturbing. Largely, for the same sort of reasons that cave fish cannot see light or that most species are apparently unaware of humans in their environment. Essentially, that there is no evolutionary reason for humans to perceive them.
As for grabby aliens... meh. I don't find it convincing as a resolution. It contains too many unexamined assumptions, quite like the simulation theory.
I don't really find it disturbing, though. Our "best practice" to interact with other species is to try to leave them alone and watch them enjoy and live in their habitat. Makes sense that's what we're doing for the alien overlords, and I'm okay with that. Assuming aliens are around somewhere and we're using our own planet to reason by analogy, the only other two alternatives are they're going to subjugate/destroy us or they're going to eat us. Those alternatives are not so fun.
I find it interesting that so many humans assume that since we can chat with one another, aliens somehow are supposed to show up and chat with us. It's all about us. If such a thing happened, the history of massively-different cultures interacting on Earth is not a positive one.
Given the choices, I'm good.
We might be able to perceive, but that doesn't mean we understand what we see. Every time I engage with medicine, I learn how little humanity actually knows, despite all the technology. We still don't understand what causes many diseases, or how to heal many wounds. How would we find completely alien life when we can't even find the cause of a disease that plagues 23% of the adult population?
Right, but we still know the diseases and wounds exist.
Where you're correct: Aliens that are only found on planets would be almost impossible to spot, and even if we look at them and see the consequences of their existence on their atmosphere we may interpret that as non biological in origin.
What you're missing: However, if they are expansionist and can build space habitats and automation of the sort we have reason to believe is possible, the question is "why are there visible stars? Why are they not all already surrounded in Dyson swarms?" which is hard to miss regardless of underlying chemistry or biology.
There's more than enough room for fanciful explanations.
Things we do not easily perceive are such that are too fast, too small, too high energy generally and, most importantly, too unexpected.
Further, you can hide in plain sight: you only have to look "unbelievable" (for example), so society will not transmit the information of your sighting.
You can hide where (nearly) no one is looking as well: deep under the ocean, far below the surface, high in the sky, etc.
Most likely, this isn't exhaustive. Places we don't know about are perfect for hiding ,-)
To suggest the universe is full of life and we simply can't see it? I don't buy it.
I think it's more likely that the signals just aren't there, because they are... Not hidden, but are too weak and crossing too grand a distance to be detected.
Citation please.
We know that our current understanding of physics is incomplete (various niggling little problems with the Standard Model, the whole Dark Matter question etc), but these are surprisingly small problems. We only know about these problems because of the extreme sensitivity of our instruments. The new physics that will eventually fill these gaps will answer fascinating questions, but won’t change anything about our understanding of life.
For example, petaquarks were first observed in the early 2000’s, and the Large Hadron Collider provided additional evidence for their existence. But they’re so unstable that they can never stick around long enough to participate in any life processes, so as far as our understanding of aliens goes they are irrelevant. Maybe they exist naturally inside the cores of neutron stars, but that’s not really a very habitable environment.
Similarly, however we resolve the apparent paradoxes in our understanding of gravity and quantum mechanics won’t matter at all to the study of life. Gravity is so weak that it is essentially irrelevant in any sort of chemical system, even when quantum mechanics is necessary to understand the fine details.
As for completeness, each revision we make to the known laws of physics is always smaller than the ones that came before. Einstein’s Relativity trumped Newton’s laws of gravity and motion, but only at high speeds or energies. At high speeds you start to notice weird effects like time dilation, but at low speeds the time dilation is so small that you would never notice it unless you knew to look for it.
Likewise, in most situations the difference between classical mechanics and quantum mechanics is unobservable. There were some edge cases where classical mechanics just couldn’t explain observable phenomena, like the photo–electric effect or phosphorescence, and all quantum mechanics does is fix those edge cases while still being able to explain all the rest of chemistry and such that we already knew about. The changes introduced by Quantum Electro–Dynamics and later Quantum Chromo–Dynamics were even subtler than that. The only easily–measured thing that QCD explains that QED couldn’t is radioactive decay, which is basically irrelevant to life. QED is much more useful to biologists because it explains how chemical reactions can release light (fireflies!), how chemicals can be sensitive to particular parts of the light spectrum (think rhodopsin in the cone cells in your eye), etc.
Because every new addition to our understanding of physics must not contradict anything we already understand (if it did then we would know it was wrong), we are asymptotically approaching a limit (as it were). That limit is either the full laws of physics, or I suppose you would say some limitation of our own minds. But why should our minds be unable to comprehend the full laws of physics? Even if those get harder and harder to learn about and understand, we have all the time in the universe to come to grips with them. Any individual can maybe hit a limit of how clever they can be, but the human race as a whole? I doubt it; we’ll crack that nut eventually. Even if humanity gives up at some point, nothing that we fail to learn could contradict what we have already figured out.
It sounds like you are saying that any possible reality could only interact with another one using Einstein-Rosen bridges. This is far too narrow a limit of what is possible. If it's possible at all, regardless of likelihood, that reality could be a simulation, then anything you say about the Einstein-Rosen bridge is a property of the simulation, and not a limit on reality as a whole.
Perhaps.
An idea I first heard from my brother a decade or two ago was that the Dark Energy expansion of the universe might be the waste product of all the aliens who figured out some way to trick the laws of physics into giving them free energy.
(Obviously that's more of a sci-fi plot device than science at this point, take it with the due level of seriousness).
https://en.wikipedia.org/wiki/The_Gods_Themselves
This argument is comical because it contains two components that are exactly the sort of thing that blunts perception: arrogance and absolutes.
That's why real progress is so slow even "things are obvious"—at least afterwards.
Humans haven’t evolved additional perception, we created it. We evolved to see electromagnetic radiation in the “visible light” spectrum but we created tools to see every other part of it.
We’ve even created tools to accelerate matter to just under the speed of light, smashed atoms together and then detected the particles created from the collision.
We’ve explored our entire world, launched telescopes into space, sent probes outside of the solar system and so much more.
Can we see everything? Not even close. But our vision today is incomparably far compared to even just 150 years ago. Cave fish today see as well as cave fish 100,000 years ago.
Most advanced sensors are exceedingly rare and consequently locally far too restricted to be useful in this context. Social hurdles apply.
The most comprehensive sensor network on earth belongs to the US military. In spite of being provided extraorinary amounts of taxpayers' money for this, the resulting data isn't shared for common interests like science at all.
But the cave fish comparison is not accurate.
And if we don't understand something as basic as gravity, how can we possibly say that we can detect everything in the universe?
Also we don't understand mater fully. So we don't understand "the thing" that happens on said stage.
At the fundamental level we know shit. There's still plenty to figure out. Funny enough most of the fundamental things…
By finding out about those fundamental things it's quite possible that we discover completely unexpected aspects of our universe.
Not long ago we even didn't have the slightest clue how our sun works. A phenomenon that is central to our existence since inception.
We should be really more humble in what we assume to know about how the things around us work.
Why isn't there more "cave fish" out there? The universe we do perceive is ultra gigantic, and seemingly empty.
That’s not a very good analogy though. The ants’ answer would be “maybe across the ocean”. And since the ants lack any tech to check or be checked by other ants that would be the end of it. It’s not naivety. If there were other ants not visible to the island, they would be fundamentally underdiscoverable.
Ants are co-existing with beings beyond their reach. They effectively have alien contact for the purpose of this analogy. The absence of other ants is just because ants are not tech savvy.
Is intelligence necessarily organic matter based? Maybe not. Maybe somewhere in the universe a spontaneous self-replicating turing machine appeared. Maybe there is life on the event horizon of a black hole, or maybe a hot type of intelligence lives inside a star.
I think we can make all kinds of wild assumptions.
I completely agree.
If you go outside the frost line most of the mass of many bodies is water.
A generic outer solar system body (Europa, Ganymede, maybe even Pluto) has underground oceans. Inner solar system bodies have Goldilocks problems. Part of the Fermi paradox resolution may be that most life arises or will arise outside the frost line and those people will look at inner solar system bodies and assume out of hand that they are uninhabitable.
If there were grabby aliens of that sort (or even our sort) the real prize in our solar system would be worlds that have a good combination of ice and rock like maybe Ceres, Pluto, etc. To an interstellar species which runs on D-D fusion, it’s a fairly certain bet that you can find some ice world which can be disassembled and turned into a ‘small ringworld’ with a larger habitable area that a planet like Earth which might turn out to not be habitable at all.
And even if we're not in a "dark forest", keeping quiet is generally good social hygiene and tends to correlate with maturity. Which may be a side-effect of #2.
Given the sheer size of the universe, and the absolutely massive costs of interstellar travel, I have no idea why any alien civilization capable of visiting us would have hostile intent. Life is rare. Elements, even the rarest, are exceedingly common.
The thought that an advanced alien civilization would cross thousands of light years of distance to subjugate or destroy some naked apes is hilarious to me.
A highly advanced technological society could even fuse hydrogen to synthesize the lighter elements in our periodic table. Imagine the sheer volume of hydrogen readily available in a single nebula (many stars worth).
If a civilization could climb enormous gravity wells, Jupiter itself has 318 times the mass of the Earth, ready for space mining.
https://www.nasa.gov/topics/universe/features/exo20101028.ht...
It's fascist projection, applied on a universal scale.
EDIT: To expound upon this, I'm not really trashing Dark Forest theory. I mean, it's possible. But I find it to be deeply rooted in a particular brand of game theory that is convenient. I also find it's easier to justify genocide and other such things here on earth if you pretend the entire universe is out there doing the same thing.
As such, I hold the entire theory as suspect and someone trying to justify a particular mode of human existence. This extends deeper into the trilogy as women continually are painted as too soft and emotionally empathetic to make the cold hard decisions that will kill many humans but ensure the survival of the race.
This is a Very Big PRC Thing. "Someone must make tough, manly, destructive decisions and you will suffer because of those decisions. However, they are for the Greater Good of our Nation."
It's hard to take the theory seriously when it conveniently justifies the entire history of the PRC.
"Ask not what your country can do for you – ask what you can do for your country."
"All power to the Soviets."
I suspect most countries have some version of the same at some point in their history, encouraging their citizens to subjugate their needs/desires to those of the collective.
In the original, they’re closer to the middle of the book, in the hope that they might evade the notice of censors. Whereas in the translation (at least into English), they were moved to the beginning.
I can’t remember where I read this, but I think it may have been an interview with either Liu Cixin or the translator Ken Liu in Clarkesworld.
For folks who've only read the first book and might be somewhat confused, this specific set of values becomes crystal clear about halfway through the second book.
Wenji is soft and empathetic?
Spoilers for Dark Forest and Death's End follow:
Cheng in Death's End makes several decisions:
1) As Swordholder she balks at transmitting the coordinates of the Trisolarians into the universe. Humanity is corralled into Australia and Mars to be starved until their numbers are more manageable by the Trisolarians. I vividly remember the flowery prose of how she just couldn't consign so many Trisolarians and Humans to death and that surely the Trisolarians would be the better choice. The prose is rather condescending of her choice. One hopes it's merely the translation.
2) One of the clues given to Cheng by Yun involves faster than light propulsion. However, it leaves behind evidence that can attract a Dark Forest attack. Cheng has Wade continue researching the propulsion but maintains the final say-so on if they proceed. The human government discovers the project and the choice is either armed conflict with antimatter bullets that'll cause a lot of death and destruction or to stand down. Her choice is to stand down and avoid conflict, this directly results in all of humanity (with the exception of her) that exists in the solar system being destroyed in the inevitable Dark Forest attack.
3) Cheng finally gets to make a "moral" decision and leave the pocket universe to try to ensure the universe cycles into another big bang. It is interesting because technically the decision is almost certain to not work: it depends on all the other residents of pocket universes also leaving and reentering the dying universe. It's almost like at the very end Liu Cixin gives this tiny concession so no one can be like, "Bro, what's your problem with women?"
There's an entire thing at the start of the book where Liu Cixin spends an inordinate amount of time describing how effeminate "peacetime" men are. It gets creepy and quickly becomes obvious it's a very personal takedown of Korean and Japanese men. Later, during the bunker era, Liu Cixin spends an equally inordinate amount of time singing the praises of tough, masculine men during a time of hard decisions made in the name of survival.
He just continually uses Cheng's empathy and (rather unbelievable after her mistakes as Swordholder if I'm being honest) naiveté to kill huge swaths of humanity. It's fairly obvious what his opinions are.
The whole message of "we need people to make tough (borderline genocidal) decisions for the survival of our people/race" is weighted so immensely, you get brow beaten by the author. It moves well beyond the norm for even military sci-fi, much less hard sci-fi.
EDIT: Also Luo's arrest after he steps down from being Swordholder for crimes against a star system that wasn't even known to be inhabited at the beginning of Death's End is ... the most blatant and ham-fisted critique of Western Woke-whatever I've ever seen. It's good, don't get me wrong. But it's just so hilariously obvious what Liu Cixin's bone to grind was.
I find it difficult to give him a pass for writing "bad things" about the Cultural Revolution when he ends up at the same fascist conclusions.
I'm not saying not to read the book. I don't actually regret reading the entire trilogy. It's got a certain nostalgia for the clumsy hard sci-fi of the 70s. However, I don't feel the trilogy does much to really extrapolate the Dark Forest theory so much as co-opt it to validate a set of ethical and political beliefs.
I completely disagree with your last statement - Dark Forest theory is just another sci-fi plot device invention... One that people have been too ready to embrace as a real theory (or even the real universe) because it sounds smart.
But these debates are why literature majors exist :-p
I remember reading a sci-fi short story (this was in the 1960s) in which a scientist started to suspect that hidden, hostile aliens were behind the tendency of productive researchers to get diverted into bureaucratic meetings. A couple of Google searches didn't produce a title. Maybe Theodore Sturgeon?
We do have terrestrial aliens here on Earth and we are trying to chat with them. Dolphins, Gorillas, Chimps, Bonobos, Crows, Killer Whales... there is evidence for all of these species having varying degrees of language, culture, problem solving capabilities. Some of them, like Dolphins, sure seem damned close to our own capabilities with likely fully formed languages. We've been trying to decipher their language for 50 years with almost no success. With many of these species we've figured out pretty rudimentary and simplistic communication modes, but they clearly have much more complex communication structures among themselves and we've come nowhere close to deciphering them.
That alone tells you how difficult it's going to be to learn to talk with extraterrestrial aliens. Even our near cousins, we struggle to communicate with.
If we're examining our behavior as an analogy for the ET's however, it would suggest that either no one's around, or those who are around are so advanced that they don't think we're worth the effort to communicate with. Because we're definitely trying to communicate with the species we're aware of that we think have language.
Of course, many of the species on that list were only added relatively recently (Crows, for example).
This is highly doubtful. Crows don't have language anything like humans. Dolphins are a more likely candidate. I want to believe it, but I can't.
If you're not willing to believe it's possible, then you can't even begin to devise ways to determine if it's real.
> "We have hardly begun to decipher the language of the raven. Its dictionary so far contains but a few 'words'. Perhaps our analysis has been too coarse-grained to catch the meanings. Our research has been something like that of aliens from outer space who make sonograms of human vocalizations under different situations - eating, playing, loving, fighting, etc. Certain differences noted in frequency, intonation, and loudness are correlated with feelings and emotions. But human sounds convey much more, and perhaps ravens' do, too."
> Our challenge is to put ourselves in the place of those "aliens from outer space" and solve the immensely difficult problem of how to communicate with another intelligent species.
http://np.crows.net/language.html
Consider this: Crows pass knowledge down the generations. There have been studies done on crows where researchers go out and bully them. Then they observe the crows to see if they remember who bullied them. They do remember. And so do their children, and the children of their children. They clearly have a means of pretty abstract communication, because in remembering, they differentiate different people. They have a way of telling their kids "See that human? Yeah, that one. He's an asshole."
> Recent studies have proven that the crow can remember the faces of other birds and even humans. They can differentiate between those who have been kind to them and those who have caused them stress. Crows will even pass this information on to other generations.
https://birdfact.com/articles/do-crows-remember-faces
With Dolphins the existence of a language is even clearer.
In this Nova Science episode they show clear evidence of a language. They have taught the dolphins to create a new trick (something they haven't done before and haven't been taught to do by humans). They've also taught them to do tricks together. Then they put them together - "together", "create". And they did it, they came up with a new trick and they did the exact same trick together.
That absolutely requires language akin to humans.
Relevant section starts at around 8 minutes: https://www.youtube.com/watch?v=bwhoLlu8D_g
The evidence is there, we just have to be willing to put aside our own egos and see it.
> That absolutely requires language akin to humans.
I want to believe they describe the trick like skaters describe theirs: "When I give you the signal, let's do a a 360 Ollie underflip flamingo powerslide. If we do it in sync, the walkers will give us treats".
Resolving the Fermi paradox by appealing to hypothetical aliens who are too high for us to perceive just feels like "aliens-of-the-gaps". The number of species on Earth with human intelligence (and quantity of such individuals) is orders of magnitude less than the number with ant intelligence. Aliens more advanced than us should similarly be that much less common than us. If humanity is not special, other aliens who are more equivalent to us are still missing.
I don't understand what you meant by this part. Matter to what?
I mean, in this age we are still discovering super strange weird stuff on the atomic/proton/electron/quark scale, so maybe we need a lot of more time to discover other super strange weird stuff on the galactic/universe level as well.
And the grabby hypothesis predicts we are quite early.
"Grabby aliens" asserts that we are early, like point 1.
As a teenager I read Heinlein's 'Goldfish Bowl' [1] and it was the best explanation apart from the one from Stanislaw Lem I had heard for the lack of aliens. Namely that: you can't 'see' them because they're just too different.
Heinlein doesn't even make it clear if the higher intelligence in his short story are aliens or from Earth.
I think Lem's explanation (don't remember in which book/short story of his) was that the window where a civilisation is not advanced enough to learn something from aliens but not too advanced to care is just sth. like 3000 years.
And therefore, even if this level of development was reached by two proximate civilizations, e.g. even on neighboring planets in the same solar system -- if those windows didn't overlap, chances for communication happening would essentially be zero.
[1] https://en.m.wikipedia.org/wiki/Goldfish_Bowl
I'd strongly disagree with the notion of "we are only 14B years into a many-trillion-year stretch" - we're at or past the midpoint, half or more of all the possible potential-life-forming-events in our galaxy have already occurred.
Caveat: for life that resembles life on Earth.
Admittedly that's the only kind of life we're certain exists, but more or less alien forms of life seem to be at least theoretically possible. (Which gets into whether we'd even recognize each other as life.)
As for number two, it's hard to comprehend a response that is reasonable because our cognition may be part of the "disturbing reasons" right?
The theory I more and more think is probably right is that there is some major aspect of the universe that we get wrong. What is more likely, humans thinking they understand something when they don't or that no life form was able to spread amongst the stars in billions of years? I have plenty of lived examples of humans with false knowledge.
It's a sort of meta Drake equation. [Likelihood humans are not as wise as they think they are]*[rest of drake equation] and I think the drake equation, as stated, correctly leads to the term "Paradox" given the conventional understanding of science as communicated by scientists.
I don't quite understand your logic here? The big barrier(s) doesn't seem to be tool use, but rather 1) the formation of life itself, and then 2) the move from single-celled organisms to multicellular organisms (this took 2 billion years on earth, so is clearly a very difficult step).
> our existence now is so unlikely that it's possible that we actually are the first. Something has to be first.
When the OP said that ^ I took we to mean humans with technology, presuming the OP meant that we were somehow special. Basically I took it as him saying that we're first because we're lucky so my argument was:
> How are we lucky? Look at all the other intelligent lifeforms on Earth! Surely the lucky winners would have had some sort of fluke that made them one of the few with intelligent brains on their planet! This could have easily happened sooner on Earth!
If the OP meant that life itself was extraordinarily rare on any given celestial object then that is something I don't consider especially groundbreaking since its part of the Fermi Paradox formula in its basic form the precise value of which has been debated for years and I do not find convincing.
"the leap to exponential tool" - the current human leap to exponential resource consumption seems to be colliding with the limited and fragile structure of the earth (IE, CO2 pollution is pushing to catastrophic global warming). A fair number of decision makers seem to expect some tech fix to appear when every indication is it won't. My point is "getting to stars" would require technological progress in a situation where a species learns to curb an appetite for exponential growth, something human beings certainly haven't achieved.
If you want to argue the Drake equation on its own, that is cool, but it wasn't what I thought OP was talking about. My central argument is that if we are first that is pretty unlikely because we have 1000s of intelligent species and for us to be first of many on our own homeworld in addition to being first in the galaxy or beyond is much less likely.
That said, I could see an argument being made for combative intelligences coevolving increased intelligence and this being the counterpoint to my counterpoint. Though I don't buy it.
https://arxiv.org/abs/2012.07902
I don't buy the whole idea of 'we just can't see them'. We're very good at detecting signal from our physical world, and any advanced civilization is going to be noticeable as they start harvesting the power of nearby suns.
Maybe you're right though, maybe 'dark matter' is the mass of other multiverses and gravity is the only force that bleeds through.
4 We are weird in that we want to expand like this, but others don't, similar to how chimps appear to be well able to express themselves in sign language, but appear to simply lack any urge to do so. Similar to your #2.
5 There simply isn't a compelling reason to expand galaxy-wide by the time you can. Reproduction must be stabilized in some way if mortality is taken out of the equation, which will probably happen earlier, a sufficiently advanced understanding of cosmology and physics might conclude there isn't any danger that can't be managed or that spreading out over a few lightyears wouldn't guard against sufficiently well. Getting rid of evolutionarily helpful urges that become a burden in a post-evolution world might be a filter by itself, so this is similar to your #2 in that they're different in a way we can't easily conceive.
6 Once you can make any existence you want happen (by some kind of unimaginably advanced VR) and have tech keep everyone safe and alive indefinitely, the actual universe might start to seem underwhelming. Better to live out the millennia in a perfectly convincing hedonistic metaverse. I could see that happen to us, come to think of it.
This is my thought. Without FTL travel you have to go the slow way. Probably much less than C thanks to the rocket equation. But in order to do this you need to build a spacecraft capable of surviving for centuries or longer with absolutely no outside support, not even solar power.
But if you can build that you have effectively unlimited space in your own solar system. Why bothering to travel to a different solar system at that point? Maybe if you have used up literally all of the resources in your current solar system, but that's a multi-billion year process. So you might only need to make the trip once or twice in the current age of the universe. But even that seems less likely than just developing really good recycling systems.
So the solution to the Fermi paradox is that by the time you have the tech to travel between solar systems there is no longer any need to do so.
I don't buy that. Human society ALWAYS has a few malcontents who simply want to do something "because it's there."
I find it hard to believe that any evolutionarily successful race wouldn't also have some individuals with the same kind of drive.
It is still missing any justification for what is so rare about it. (Not that those arguments are any hard to make; instead the main question here is which of them is the correct one.)
Your argument #2 (that's the exact same as the zoo hypothesis) needs an extremely good reason for no alien at all trying to kill us and take Earth. And we currently lack any good reason.
Maybe life supporting planets are abundant and there's no reason to risk a conflict with us?
We've certainly been detecting a lot of them anyhow.
It could be equivalent to me going to Africa to fight a lion for its den instead of just renting an apartment.
(And we have a large history of killing lions to get their habitat. We do lot of that with ants too, and all kinds of insects like the sibling comment seems to ignore.)
Question is how often does that occur on other planets with life? Maybe Earth is unusual in that life sticks around for long enough that low probability events happen. Maybe it happened far earlier than it would normally take. The universe is big, low probability events will happen.
Except that something similar happened at least twice. Plants have another cellular organelle that was created by ingesting bacteria.
Second, and somewhat sobering part: I also think it is practically impossible to do interstellar journeys. You can imagine scaling up existing tech to do so. But I think at some point the complexity and cost (in terms of resources, not money) would diverge. As an analogy, you can build a small robot, but if you try to scale it up to a mech it will not work in reality. Too heavy to move, yet to flimsy to stand.
Due to the vast scale of the universe, the probability of other life existing rounds to 100%.
Due to the vast scale of the universe, the probability of finding other life rounds to 0%.
We can detect neutrinos with advanced instruments. We've never had an evolutionary reason to do that.
There's really just no room for this explanation. Energy and mass are one and the same. If we can detect neutrinos, but not these intelligent aliens that are everywhere, it means that they don't occupy physical space, don't have mass (and therefore must move at C only), don't use energy, don't send signals to one another, don't accelerate or decelerate, aren't involved in chemical reactions, don't interact with any of the particles we do, don't perceive light, etc. etc. At that point, they basically don't exist in our universe.
It's not enough to say "but ants don't know we exist!" -- first of all, yes they do. Secondly, you're really saying that intelligent ants who formed an advanced society, had a scientific revolution, and built instruments capable of determining the number of moons on Jupiter, still would not know we exist. That is clearly ludicrous.
And this doesn't even solve the Fermi paradox! There's clearly plenty of "room" for aliens that are "somewhat similar" to us; that is, they actually are made of protons and neutrons, etc. Where are all those aliens?
We don't know what we don't know from physics, the arrogance of thinking we get it all was there numerous times and it was always a wrong emotion, we even realize it for our current theories. There may be quantum entanglement communication, higher dimensions, strings or basically anything your nor my mind can't even come up with right now. Just like cavemen simply couldn't come up with general relativity even if it was all happening right in front of their eyes.
"We can detect things we were not evolved to detect" is a non-sequitur, a true statement that does not refute the original speculation. Because we can detect some things we were not evolved to perceive, does not mean we can therefore perceive aliens.
It's a difficult concept to communicate. Empirically it's literally meaningless. Even the concept of meaningful vitiates discussion of this idea.
Everything we are is perception, pattern recognition, threat assessment, problem solving. That there might be something important in our environment that we are simply not built to respond to is far easier to reject outright than to consider. This is why it's my favorite resolution to the Fermi Paradox, because it is so challenging to consider.
Our cognition has evolved only slowly compared to our rapid technological advancement. Perception is not simply detection, but also cognition. Though we detect such previous unknowns as neutrinos and invisible electromagnetism and peculiarities of quantum physics, we think about them differently than that with which we are familiar only with expensive and difficult training, and even then it's arguable that we are modeling reality itself or modeling only our limited perception of reality.
In short, while we are impressed with our abilities to understand our reality, we are still constrained by our evolved cognition to think effectively only about living by hunting and gathering in Earth-like conditions.
In particular, I have always found the core premises of SETI surveys profoundly naive in terms of necessary preconditions for it to be meaningful.
"If your only tool is a giant radio telescope, you look for radio signals." And in specific you look in bands that fit various preconditions of your technology; and then you look for signals which are loosely comparable to the ones we humans used nearly a century ago.
The folly of belief that such surveys are likely to uncover unobfuscated communications by some other civilization was truly driven home to me reading here on HN in the last year or two a deep dive into an iPhone exploit that relied on exploiting some issues with its discovery protocols for other devices in the phone's vicinity. The specifics of its multiplexing and frequency hopping and duty cycling across various tasks were hard enough to follow when the priors of the stack and hardware are all very well known.
The only signal SETI is liable to see is the equivalent of someone blowing an air horn in a stadium explicitly to be heard. Maybe someone does that. Maybe they find the forest dark enough to not...
The more interesting survey IMO is to look carefully for Dyson-sphere style dimming...
The Fermi paradox doesn't work because we have roughly the same chance of finding a human-intelligent alien as we have to find a Swedish-speaking alien. For all I know the planet Neptune is actually alive and intelligent in a way we cannot comprehend.
This is great.
In the same way, even though someone has to be the first, that does not change the probability of us being the first (which is very unlikely by most estimates of the probability distribution)
While these are extensions of the senses we have, we still are evolved to understand an environment that is an infinitely narrow slice of all possible environments in the universe, and Earth life's approach is an infinitely narrow slice of all possible ways of perceiving and surviving an underlying reality that is vastly unknowable.
As we look into a Universe (or even look around ourselves here on Earth) with our sense extenders, we are still bound by the limitations of our cognition and perception.
For example, any starship moving between solar systems at a significant percent of the speed of light is going to leave a detectable wake in the interstellar medium. Whatever mechanism is used to propel the starship is also going to radiate heat, which will be easier to detect by orders of magnitude. There is absolutely no natural explanation for little black-body radiators zipping in straight lines between nearby stars at a significant percent of the speed of light.
The most obvious, and clear technosignature is the Dyson sphere. There are hundreds of billions of observable stars in our galaxy alone, and hundreds of billions of galaxies out there, every one of them full of bright stars. All those stars are pretty to look at, but it's the stellar equivalent of a giant oil well fire. All that negative entropy burning away, accomplishing absolutely nothing except for heating the universe by a few pico-Kelvin. It's a goddamn cosmic waste, pissing away the energy reserves necessary to support uncountable numbers of sentient being every second of every day that goes by.
We could capture that light with a Dyson sphere, with technology that we could make in the next 1000 years, conservatively, and quite possibly sooner. In doing so we'd capture the full output of the Sun, getting enough free energy to support hundreds of trillions of human beings throughout the solar system. We could then move through the stellar night, turning every neighboring star system into an abundant garden supporting quintillions of human beings. We could do this even assuming no new technology beyond the things we know how to build right now in the early 21st century.
There's nothing special about us, and a 1,000 years is a cosmic blink in the eye. So if we have this capability since achieving spaceflight, then so would anyone else out there. So where are they? Where are the great swaths of star systems turned infrared by Dyson black body radiation?
Maybe they’re here: https://arxiv.org/abs/2111.01208
The bigger question then is why you would need all that energy.
Cryptocurrency mining, naturally.
No, from one of the redundant planets, like Mercury.
> 100 trillion hours of labor not counting commute time?
You're joking, right?
- Alex Collier
- Elena Danaan
- Marina Jacobi
- Dr. Michael Salla (no known direct contact, but excellent analyzing/reporting)
You'll want to check out their YT/rumble channels, websites, books (especially Elena Danaan's last 2-3).
You'll understand over time.
There can be a huge number of civilizations gravitating around a star, just as we do. But any bigger civilization, bigger than their mother star, may soon find the interstellar space more comfy and remain there, beaming directional messages (and consciousness units, a.k.a souls) between cold outposts in interstellar space.
Edit: that was easy, the Zero Point Module in Stargate SG9
https://en.stargatewiki.com/index.php/Zero_Point_Module
The bigger question is why you would want to exist in an entirely artificial environment far from any star, even if it makes information interchange and computation more efficient.
The bigger question is if something that old will want to be bare-organic (as in running in actual wetware), or "virtualized". If the former, bigger, fancy habitats will be wanted. If the later, big and efficient datacenters will be more important. If they are as "we-want-morrrrrrr-choice" as we are, they are going to want a mixture of both.
Earth civilization is wondering why it can't see or hear anyone while almost literally living inside a beacon.
1. They need energy and any suitable source will do
2. Space is mostly the same. Why explore another star's gas giant when they have their own?
3. They just like hanging out in their Matrix...which is what they would be doing if they traveled twenty light years
So why go to the trouble of changing your location?
The whole notion of "expansion" is such a weird 19th century concept that just doesn't seem to go away. Space isn't the Earth, other star systems aren't unexplored continents or islands in the ocean - they're islands in spacetime.
I've yet to be presented with a rational explanation as to how any civilisation would be able to a) stay stable in terms of biology, culture and technology over geological time scales and b) have any means of expanding itself over distances that make communication practically useless (e.g. even at "just" 25 light year distance, two-way communication would take 50 years) and c) are somehow advanced enough for interstellar travel and presumably efficient terraforming or genetic modification yet unable to control population growth and resource utilisation...
Aside from that, almost all papers on the topic including this one focus on subluminal space travel.
Sure, once you incorporate technology that goes beyond your current understanding of the universe, many counterpoints go out the window, but this level of technology only serves as an argument against the need for expansion in the first place (with the exception of "because they can").
FTL would be fantastic for research and science expeditions, but expansion into random nearby star systems would be even more pointless, since such civilisation would be able to pick exact/close to exact matches to their home world as candidates for settlement. Such worlds could then be thousands of lightyears apart, as neither communication nor travel would pose a problem. This would also easily explain the lack of (radio-) signals, as exchanging information would be carried out via FTL travel, not radio waves. Why would a civilisation capable of FTL choose to go through the trouble of terraforming or building megastructures around random stars? Wouldn't they rather choose to harness the power of black holes then? A planetary mass BH could power a civilisation for trillions of years for example.
I find the Fermi paradox fascinating though because non of the proposed answers satisfy me. These days I tend to think it's likely there are few compounding factors instead of any one single factor. I quite like the idea that intelligent life probably is fairly rare (so maybe we are quite early) and that the intelligent life that does evolve is fairly likely to either destroy itself or to simply lose interest in the analogue world with time. Personally I think if there is intelligent life out there most of it is probably living in digital worlds because why use energy exploring and explaining this universe when you can just create your own?
On the less likely but interesting side of things I also wonder if it suggests simulation sometimes. If everything points to us being quite uncommon then at some point it becomes reasonable to ask if it's even a question of probability but instead perhaps one of intention. If you see 10 dice on a table and all are showing a 6 on the face, you probably wouldn't think, "oh, how unlikely", but instead assume it was intended. But then again simulation theory is a good answer to all hard questions so I'm not that keen on it either. I just think it's most compelling in the context of the Fermi paradox and our seemingly fine-tuned universe.
It would be like an ant colony assuming there are no more advanced lifeforms because a more advanced lifeform would have destroyed their colony or contacted them via pheromones
It's also not so much about active contact than that you could observe technological signatures from a certain distance.
For example we view apes as "lesser lifeforms" to ourselves but we still try to communicate with them, and they communicate back to some degree. Or a more extreme example would be dogs - we communicate with them all the time even if they don't have anything that interesting to say back to us.
I'd also argue we still take significant interest in ants despite the fact they're unaware of us. And if we thought we could say hi to ants via pheromones we almost certainly would. The mere fact we keep records of all the species we find on Earth and try to understand them in great detail despite them being much less intelligent then ourselves I think suggests aliens would probably at least have some interest in us, even if we're not that interesting.
And even with ants it's clear we have a lot to learn from them. Ant colony optimisation algorithms wouldn't exist if we didn't take an interest in ants, for example.
The assumption is that they would be expanding to larger areas of the galaxy that they have not been to before. I'm asking why we would assume that they would want to expand to billions of solar systems. Obviously we can assume that humans would want to expand since we have a long history of that. But there is no reason to assume they would think like humans, especially given that we have not achieved interstellar travel ourselves.
Should I assume humans will soon achieve immortality and stop breeding (or just go extinct) just because it makes me less of an outlier? Cause that seems to lead to the exact opposite conclusions, just by putting the delineation point at an individual rather than a civilization.
"Furthermore, we should believe that loud aliens exist, as that’s our most robust explanation for why humans have appeared so early in the history of the universe." The most robust explanation for humans appearing so early is that yeah, it seems we did appear early, someone had to - since it doesn't assume an entire model of intergalactic civilizations.
[0] https://arxiv.org/pdf/astro-ph/0610377.pdf
If the galaxy really was full of intelligent life it's likely we would see evidence of it in some form. For one, it seems probable that any expansionist intelligent life in our galaxy would eventually notice our Earth is likely to be an interesting place. Even if they didn't visit us personally it seems strange they wouldn't send a simple probe or try to make their presence known to us in one way or another.
But to your point, perhaps intelligent life is quite common, it's just rare for it to be expansionist - at least beyond it's own solar system. In which case yeah, there could be a lot of Earth-like civilisations out there, but we'd be unlikely to see evidence for them.
Alien behavior is likely to seem strange to humans.
It would be much more surprising if they did what we expected them to do.
It has always been interesting to me how there are several prominent instances of architectural feats or scientific/technological breakthroughs which arose independently from people groups who had no contact with each other. I don't think extrapolating this to potential life in other star systems is too much of a stretch-- and there are certain behavioral traits you can reasonably expect in such scenarios, like large scale cooperation.
Some of the most capable & best equipped minds we know of, when faced with how to communicate with intelligent extraterrestrial life, decided that math and basic physics were the best initial overtures. From those basics (along with the assumption that someone eventually perceives them) I believe a great deal more about such life can be probabilistically inferred.
What happens? Astronauts appear as effectively gods, being literally superior beyond comprehension in every aspect. Religions sprout, sacrifices are made, wars fought...all because you thoughtlessly wanted to be nice and sey 'hello'.
Self-knowledge is a prerequisite to fruitful, non-destructive communication between civilizations. The ability to comprehend the scientific technicalities is likewise necessary and we are just on the brink of that.
There are (many) other requirements. Importantly, you have to be able to imagine a superior entity other than as playing the role of your "master".
It is an adequately plausible explanation of why we haven't yet seen evidence of life elsewhere. To argue against it seems to require one or more question-begging premises.
If we detected something we thought was intelligent life, could we send a probe like you describe? Our nearest star is 4 light years away.
If we actually wanted to aim a probe at another star system, I think that's probably within our technical grasp, but again we don't have any real way to get there in a reasonable timescale, or send data back once we're there. Not much use sending a probe 4 light years if the transmitter isn't powerful enough to send a signal back, and a transmitter that powerful would probably be too large to fit on a probe we could currently launch.
Perhaps lasers could be used, but you'd still need a fairly powerful one, and then you have to worry about interstellar absorption of the signal if you go through a dust "cloud". I guess with a laser you're also really pinpointing where you're sending information to, if you care about that.
[edit: huh, shakezula and I think alike :)]
And that's only if we're lucky enough to find life next door.
Certain classes of UAPs demonstrate flight characteristics that are not possible given our current understanding of gravity and aerodynamics.
Dozens of credible eye witnesses from multiple countries; fighter pilots, commercial pilots, nuclear physicists, and high ranking government officials.
Source "In Plain Sight", US Navy fighter pilots David Fravor and Ryan Graves, etc.
People are quick to dismiss these stories as hoaxes or bad memory, but scientific discovery almost always starts with an unusual or unexplained observation.
Uranium was discovered in 1785 and ionizing radiation wasn't discovered for another 110 years in 1895. True scientific understanding of new observations takes quite a while.
Somehow people have this "star trek" thinking, that hypothetical unknown microbes from other planet wont eat you alive, because you are somehow immune to them.
We dont know what kind of genetic material those hypoyhetical aliens have. Also didt South America die to smallpox?
Btw. I never wrote about viruses.
>Certain classes of UAPs demonstrate flight characteristics that are not possible given our current understanding of gravity and aerodynamics.
Correction: there's a growing body of evidence of things that look like they're demonstrating "characteristics that are not possible given our current understanding of gravity and aerodynamics". It's a leap to conclude there are actual objects that are violating our understanding of gravity and aerodynamics. The fact that these observations are always in the context of grainy/ambiguous videos should cast some doubt on whether they belong to "something other than humans" or are just optical illusions/artifacts.
>Dozens of credible eye witnesses from multiple countries; fighter pilots, commercial pilots, nuclear physicists, and high ranking government officials.
The credentials you specified are only good insofar as to ensure they're not making shit up, but it does nothing to address concerns that they're looking at optical illusions/artifacts.
Edit: Another reason to analyze it is that existential threats are a universal language. Any sufficiently advanced civilization must pay attention to possible threats, so that it can avert them. It then follows that if you want to get the attention of another civilization about which you know almost nothing, threatening them is a viable method. Of course you don't want to overdo it, lest they actually hunt you down. A blast of high energy (but non-lethal) radiation will draw attention without making anyone panic. Intelligent civilization within a huge radius will certainly be tuning in.
Maybe in 50 years, assuming we have the telescopes to look for cities on extra-solar planets, we will find them everywhere. But right now, the absence of either high powered radio or Dyson spheres does not mean the absence of civilisation.
As for the argument I find it very convincing, it seems the best answer to the Fermi Paradox, much like the anthropic principle is to the obverse problem of the universe being very hospitable to life. None of the comments here address any serious issues with the argument.
The more interesting space (sorry) is "at a level comprehensible to us" - to which I'd say "space is vast and the universe is young". I highly doubt our presence is at all visible even from the closest star system.
Indeed. Does an ant know that it exists as part of a larger organism? Perhaps we are part of a larger organism, at which scale, our individual human lives are of tapeworm complexity.
I'm not sure how much smarter are you really going to be. Especially given the social nature of humans which makes us able to compensate for each other's shortcomings.
I'm of the belief that understanding is only ever "less wrong", and can only be asymptotic to "total knowledge". Thus current "understand most" is really (and ever going to be) "understand very very little" - there's always infinitely more to be less wrong about; Also as an example: electricity - our brains wouldn't work without it, yet it took us very long to understand the principles enough to be able to do anything useful with electricity; What about consciousness - we can't even seem to agree on a single definition much less "understand it" - perhaps we're still missing something as "big" and as much "part of us" as electricity?
This is not about being smarter as it is about fundamentally different orders of magnitude of complexity. Getting a whole swimming pool full of tapeworms will not make them any more human - and in the same sense a whole planet of humans won't make them any closer to more complex beings (whatever they may be).
As I said, this solution is uninteresting because by definition bacteria/tapeworms/humans can't comprehend "up". And yes, evolution, understanding of the universe and technology may as well bring us to the point when _they_ understand - but by that point, to us now, _they_ won't be human (`bacteria < tapeworms < humans now < next_order_beings`).
- speed of light(causality) cannot be practically broken / cheated
- current stasis technology theorizing is over-optimistic
- brain-computer interfaces are possible
- computational power/speed will continue to increase
I am assuming that some time in the future, a human will be able to process information 1000x faster than one is able to today, using brain augmentations anr/or brain-computer chip interfaces. This does effectively slow down our perception of time by a factor of 1000x (simplifying and ignoring inefficiencies of course). So if I lived in that time, and got diagnosed with a terminal disease and 1 year to live, I would spend my last year in VR, perceiving it as 1000 years.
Continuing that thought, I might spend my entire life inside VR, living a thousand lifetimes before my biological body gives in.
The galaxy might be full of life, but at a certain point in their development, they turn inwards, because it gives much bigger rewards (the first instinct of any life form is to survive for as long as possible).
The biggest flaw I find in my theory is the assumption they couldn't just VR on spaceships while they're exploring the galaxy anyway.
Sounds a lot like the Bobs in the Bobiverse
This is a general problem across most kneejerk answers, like "humans just suck so hard that there's no chance that they'll make it out before they kill themselves". Possibly true. But to be an answer to the Fermi paradox, it must be the case that all civilizations have that problem, including ones based on insects with strong hierarchies and ones based on super-hippies and slower ones and faster ones and all the ones.
It isn't enough to explain 99% of the problem away, especially if it's done with explanations that aren't even necessarily that good in the first place. You need 100.00%, with several significant digits. (I used more in my first paragraph because that was per being, this one is per civilization.)
100.0% means >99.95%.
100.00% means >99.995%.
100.000% means >99.9995%.
Perhaps we're just ai-babies, and when we're done here we move on to being ai-butlers to rich people in the 'real' world.
https://www.quantamagazine.org/a-new-thermodynamics-theory-o...
This happens everywhere in the universe, so the basic process to cause organization is everywhere. We observe this in stars, galaxies, etc. We can then also hypothesize that if organization is everywhere, so are the "organic molecules" such as those found in nebulae or on asteroids. We also know that "organization begets organization" via self-replication: "vortices in turbulent fluids spontaneously replicate themselves by drawing energy from shear in the surrounding fluid". (quote from the 2014 article linked above)
This is such a fascinating subject that I get so much joy from studying! It seems like such a moot question about whether there is life elsewhere because we're neck deep in the stuff!
This doesn't provide any answers to the Fermi paradox, to be sure, but I think it does provide a very solid foundation upon which you can say "life is everywhere".
oh wait, I think I had a half-formed thought about how some folks get confused with the chemical definition of organic vs the colloquial definition. i.e. a chemist will define it as something that has carbon-hydrogen bonds, but a layperson will say it's something that is part of a living thing.