So you know the Great Filter, right?
It’s what happens when you look up at the stars and ask “Where the fuck is everyone”.
There are so many planets out there, yet it’s radio silent. The intelligent life to planet ratio is really, bad. So far we’re the only ones.
You gotta ask, why?
Enter, the Great Filter. Something, at some point in the pipeline, prevents planets from developing and maintaining intelligent life capable of electromagnetic communication.
We don’t know what it is. Maybe it’s a quirk of chemistry that makes the chance of multicellular life forming ridiculously low. Maybe it’s a quirk of biology that makes sapience incredibly rare. Maybe it’s a hyper intelligent space worm that eats any civilisation that makes too much noise. Maybe it’s runaway climate change.
The thing is, we really don’t want to be on the wrong side of that filter, because that suggests that an imminent demise is in our civilisation’s future. And with every discovery of non-intelligent life on other planets, it becomes increasingly likely that we’re on the wrong side of that filter.
Enter, the recent discovery of life on Venus. It means that we’re much more likely to be on the wrong side.
But, watching that debate tonight, I began to feel a sense of relief. At least if we’re on the wrong side of the filter, it’s not as though we’re wasting a once-in-a-galaxy chance. We’re just yet another civilisation that failed to get past that filter. I can live with being unexceptionally mediocre.
Any contact with an alien civ will be disastrous to us or them, for evolutionary goal orientation/economic material conditions related reasons. A parasitic wasp is likely to be far closer to us in habits and desires than anything we'll meet out there. So either we meet and one wipes out the other, or we meet and one forcibly changes what we want as a species. Kind Civs would just lock them in a reasonable size bubble and move on.
Luckily, unless they're super stealthed or very young, there are no Type1+ Civs in the Milky Way unless we are very, very bad interpreting our astronomical data.
No Dyson swarms anywhere, No Sentient star clusters, No Black hole energy factories. Not even tight beam laser traffic within 5000 Lightyears. Not a trace of stellar scale mega-engineering to be seen.
Of course, further out there's the Bootes Void and the Great Voids, Which are just a bit too large for standard cosmology models to explain, have a few very bright galactic clusters in the centre, and look an awful lot like someone turning off all the stars to conserve electricity (Hydrogen). We've got time before they're a problem, though
Of course, there's the other possibility: There's no way to 'cheat' around relativity. Alcubierre drives are already posited to have the problem of creating massive bubbles of energy that would atomize the star system they're being used in. Tachyons are becoming less and less likely.
Maybe the answer is that interstellar civilization just isn't feasible because the distance between stars is too great, and thus acquiring the resources for these grand space projects is an exercise in futility. A universe that isn't condusive to dyson spheres, or matrioshka brains, or multi-stellar polities. It could very well be that at best, the most advanced civilizations are a singular well-populated homeworld with a few small research colonies on other planets in their own solar system and maybe a few extrastellar colonies fed by generation ships that are just as likely to fail on their way to their destination as they are to make it there.
My worst nightmare and seemingly the most realistic. It just makes things boring compared to the sci-fi I've consumed my entire life.
You are thinking a bit too small. It would take, at the most conservative estimates 40 million years to conquer the Milky Way by small sublight constrction probes. That assumes no ftl, no advanced nanotech, no uploading or superhuman ai and no radical life extension.
If you dont care about how long its going to take its more than possible. And every single intelligent civ has to decide this is too much effort for its entire lifetime, when it would take trivial energy expenditure for it to begin and the rewards would be extensive ("let's start moving more stars towards us for power", for instance)
I mean, I don't see it as that unlikely. A consistent interest in a vision of expansion is in and of itself a feat, especially over millions of years, and more than that it's entirely within the realm, if not outright very likely, that sapient species in the industrialized, space-faring level of existence just aren't common. As you lower the numbers, the likelihood of them going "yeah, fuck taking a million years to accomplish something" as a whole becomes more and more plausible.
The science of nanotech is also looking less amazing than initially thought, what with needing to keep them continuously powered, running into barriers of just how small you can make a computer and have it follow complex commands and so there's that, and uploading also comes into certain barriers already well-tread by anyone who's dipped into existential philosophy and Ship of Theseus and yadda yadda you almost certainly know the arguments and are probably bored of them by now. Rapidly self-improving AI is... Well, I just don't expect the Yudkowskian vision of a singularity sparking superintelligence that will kick us all the way up the Kardashev scale.
Hell, if you want to move away from the problem of no relativity cheating, there's all sorts of other problems. If you want a space-faring species, you have so many hurdles to overcome. Naturally aquatic? Well, water and fluids in general are a lot heavier than gases and also a very disruptive to sensitive equipment. Carnivore or similar tertiary consumer? Good luck forming a sustainable urban society without causing a massive ecological collapse even faster than humans can. Hell, we don't even know if any of our senses are common out there in the cosmos. Sight seems almost mandatory if you're going out to space - optics are basically a necessity to let you know there is shit up there. Then of course when you're outside your ship, sound's not particularly useful since it needs a vector to travel through Maybe some sort of radio wave sensitivity would help. Of course a species would also need to be sturdy enough to stand the force of take-off into space, and also not die from extended time in zero-g (a problem we ourselves face). Could be there are plenty of species we would consider, in some way, intelligent and even sapient that just can't leave their planet for one reason or another and we are an anomaly on that front, being not so much 'suited' to space travel as... more capable of it?
Or maybe there is a lot of spacefaring life but it's all so alien that even their structures and priorities pertaining to those structures are so vastly different from our own that we wouldn't even recognize what they've made as the product of an intelligent species. I've been mulling this over while very tired so my point has probably been muddled severely. Sorry.
Would stellar megastructures even make sense at all to be built? We all imagine the future as large space ships and dyson spheres and crap, but maybe it's fusion electricity and everyone living in a pod plugged in an anime matrix.
Yes, it's possible the great filter is "everyone plays computer games". But you can run much better computer games much faster on a Matrioshka brain.
That's also an answer, the accelerando hypothesis they all uploaded, spent upwards of a trillion subjective years doing stuff we can't imagine, and decayed in a few thousand objective years. Still, we should be able to see the ruins, but I'm not sure we've checked for what a Dyson swarm looks like after a billion years of neglect.
The issue is it has to explain every civ from every plausible origin. It just takes one species to go expansionist in the real world and suddenly our planet is getting devoured by nanobots.
To me at least on paper a super large computer just sounds dumb. The smaller the computer the better. The larger the scale the slower the communication between parts. And if you want a super large network of computers, to me it makes way more sense to distribute that on the surface of the planet instead of hauling it to space. And hell cooling and powering it would be easier on earth probably, too. And of course a space computer will mean that anime matrix ping would be shit.
Expansionism may be impossible, because of the scales involved and the impossibility of faster than light travel. I'm not sure how feasible those super large generational ships that are common in sci fi are. Maybe there isn't an energy source that could get you into the next galaxy and power your ship for centuries/millenniums. And honestly, it takes one accident, one civil war or mutiny, and the generational ship is over.
It's not one computer. It's a very large number of networked computers in a swarm around the sun. The first shell uses the sun's light, the next shell uses the waste heat from the first shell etc. Its true there's a trade off between complexity of the computer and speed, you'd have microscopic fast thinkers mediating more complex machines all the way up to "jupiter brains"
The problems of interstellar travel are easily solved by Von neumann probe. It's very unlikely that your alien invasion is by anything bigger than a coke can. It hits the outer Kupier belt and begins building. By the time you notice it's too late. Swarm noms solar system, turns it into habitat for host species if that's it's thing, makes a bunch of probe copies and launches them.
I still don't get how that computer would not overheat massively, current computers need cooling solutions and so would any complex computation, the computer is also getting blasted by full spectral radiation from the sun. Current electronics and ultra violet-gamma ray spectrum go about as well together as snails and salt. I honestly don't know what kinda computation wouldn't get interrupted by it. Biological and optical solutions would have problems as well.
And of course, anime matrix ping is still shit.
You make it a diamonoid (possibly ferrousoid to prevent melting on the inner shells) molecular rod logic device.
You also make the architecture reversible to reduce heat, now most waste heat is from the entropy of the mechanical operation.
stirling engines on the front to reduce the light to usable energy, heat radiators on the back to cool, computation moves down the energy gradient.
All of these elements are very small.
The ultra violet-gamma spectrum will run havoc on molecular logic device, as well. And probably more so than on a transistor. Heat will also breakdown the molecules. And just radiating heat away is not feasible for the current computers (that are also around cold air, don't have that in space), but it will be enough to cool of a future computer, that is also being blasted by the sun?
And my waifu is teleporting all over the place, because anime matrix ping is so dog crap.
Real "A Topiary" hours
might be the only reason we evolved was we lived in a giant, quiet void