Okay, I can agree with that. Exactly 1.0 for an exponent is not particularly likely. I just threw that out there as a *possible solution. Hell, maybe the galactic federation limits expansion such that you can only do it when your star is dying, enforcing the 1.0 relationship. But perhaps the exponent is < 1 for reasons we have yet to understand or consider, and civilizations either die before they expand, or they manage to expand for a little while before dying out. Or maybe civilizations do expand exponentially at first, but eventially run into other civilizations that attack them and stop their expension, much like ants that encounter other anthills instinctively go to war with them rather than join into a giant anthill.
The only real point I was trying to make in all this is that the question of “Where are they” can be answered in many ways that do not include “we must be alone”, or “there must a great filter”. Instead, we might accept that we know so little about the universe and our galaxy that we can’t even formulate the equations or terms necessary to answer the question.
And given the nature of coplexity and how it seems to show up at every scale, the situation the galaxy is in with regards to life could be incredibly complex and governed by rules we have yet to discover - physical, social, whatever.
< ETA: Sorry @BlinkingDuck, this is not a response to you. I can’t seem to get rid of that. >
I think some are getting a bit sidetracked on the topic of civilizations spreading out and colonizing worlds.
Because, once again, positing that no species wants to do that is not actually very helpful to the Fermi paradox.
Launching probes is something that will be pretty cheap for humans in the near future. Self-replicating probes could be littering the galaxy if even one small faction of one species ever decides to launch them. We don’t see evidence of any such probes yet.
Or, any kind of megastructure. Yes, we talk about Dyson spheres, but that’s just an example of a megastructure that we can conceive of with a purpose. Who knows what kind of megastructures might fulfill purposes we are not even aware of yet? And yet, we don’t see those either.
I don’t claim to know there are no advanced ETs. In fact, I suspect that they are out there. But we should take the (lack of) data that we have seriously. The empty skies are a data point. On its face, the data we have, suggest no advanced ETs yet.
I was with you until that.
I agree that most likely there are many filters and many unknown unknowns.
But, based only on what we know right now, it is rational to be concerned that a filter or set of filters lies ahead of us.
I’m not seeing it. You’re imagining a species that spreads out rock by rock, right? And each time they drill down for the resources they need, develop the infrastructure, then move on once the population grows. Right?
Where are you getting the food? Are you traveling with a farm?
And you can’t just ignore the possible health risks of extended space travel, or living at a lower gravity, for a lifetime. Our current studies (I linked above) suggest that genetic defects and inflammation may be increased, for example.
These are just two brainstormed ideas.
Ultimately, my argument is that it is not a fait accompli that an intelligent species will fill out the galaxy, given enough time. A solar system? I can buy it - although it would reflect an incredibly advanced culture. But I reiterate that there may simply exist practical limitations that prevent galactic expansion.
They could, but that doesn’t mean they should. I think it’s a mistake to imagine things that could exist, then try to draw conclusions when you don’t find them.
I don’t think they do. They don’t provide evidence in support of ETs, but that’s different than concluding that there is affirmative evidence of no ETs. At best, we can say that it’s an unproven premise, and relies solely on logic rather than evidence for support.
Uh, but the point is that poker, like all gambling games, is an artificial construct designed to have sufficiently high risk, and sufficiently rigid criteria for win or loss, to guarantee wiping out all players but one in the timeframe of the tournament.
Re-design the rules and the odds somewhat, and you could quite feasibly have a World Series of Poker whose expected duration to get down to one remaining player would be several human lifetimes, or longer.
Moreover, the basic rules of poker don’t intrinsically change the longer you stay in the tournament. There aren’t sudden massive increases of power or risk such as automatically eliminating your left-hand neighbor if you happen to draw the ace of hearts or automatically bankrupting yourself if you get a pair of jacks.
For human technology, though, both power and risk do greatly increase as a species develops. No 18th-century society could conceivably have destroyed all human civilization outside of a few scattered remnants, for example, but several 21st-century societies could plausibly do so.
Not saying that you’re necessarily wrong about the nonexistence of a “great filter”, just that your chosen analogy doesn’t really support your arguments. Yes, perhaps human technological development is just going to keep moving along unless and until some random comparatively small risk eventually torpedoes it, rather than inevitably running up against some insurmountably huge risk. But if so, it won’t be because the process is meaningfully comparable to the artificial setup of rigorously randomized small risks and inflexible success criteria in a poker tournament.
Well, by the time they achieved it they would have no longer been in the 18th century, though. 21st-century societies have the material means to wipe out most of humanity in a much shorter period of time.
That’s convenient: if there are ships in the sky, it’s obviously supportive of the position that they are out there. If there isn’t…it can just be ignored, it’s no longer a data point.
Look, I want to think there are people living on my street. But, if I have telescope that can see all the way along, continuously, and I never see any people, or any cars, or any lights on, or anything being delivered…I should accept that data.
It doesn’t prove that nobody’s home (and yes, obviously we can list potential ad hoc explanations). But, in itself, the data is more supportive of the position that no-one lives here than that someone does.
I assumed you just meant an 18th century tech level, not literally the 18th century. Technological progress could have stopped there; maybe because it was at the intellectual or organizational limits of the civilization in question; or maybe the planet they inhabit lacks some key resources for making further progress, like oil; or maybe political issues cause stagnancy; etc. It would only take a few centuries to ruin the biosphere quite badly.
I’ve never thought about it like that. That’s a hard one to digest.
That’s absolutely true. I think there are 3 possibilities here:
Our telescopes are not good enough to see whether earth-sized planets even exist, much less whether they have artificial satellites orbiting them or other sure signs of civilization. So instead of a telescope, we have …basically nothing and we’re blind as a bat. This is the reason why we keep hearing about “super-earths”. because they’re big enough to slightly alter the luminosity of their star when they get in the way, and our spectrographs capture that…
techno-people are too short lived and/or too rare to be able to communicate meaningfully each other. Like, if Proxima Centauri had a planet with living techno-folks, we could talk to them. It would take 4 years between each sentence, but we could have a vastly parallel multithreaded conversation between millions of Earthlings and Centaurians. But as far as we can tell, nobody is broadcasting to us from there.
We’re the chosen ones. We were lucky enough to hit the winning number at the survival & evolution roulette 10 times in a row and we are responsible for keeping the flame of consciousness alive, and spreading it in an ethical way in a dead unthinking universe.
I was referring to the aforementioned megastructures. Our telescopes are good enough to rule out several classes of megaproject, without us ad hoc supposing that all megastructures are cloaked or whatever.
Again, this isn’t that relevant to megastructures, self-replicating probes etc, as species don’t need to be coexistent for these to be extant.
Could be. It may also be the case that sentient life will be common but we are among the very first.
Lots of possibilities, and that’s why it’s fascinating.
It’s just slightly annoying that the Fermi paradox is often presented as the claim that intelligent life should be common and hence that the paradox is “solved” by questioning such assumptions.
There’s a huge set of unknowns here…nothing is “solved”
I take the same position on this as I do with respect to god (or… any other claim about reality). The time to believe intelligent life exists somewhere else in the universe is when evidence of intelligent life somewhere else in the universe is presented. Not before. This is not the same as believing there is no intelligent life elsewhere in the universe, it is simply the absence of a belief that intelligent life exists elsewhere in the universe. No evidence has yet been presented, and so I remain unconvinced, nonbelieving. I am no more persuaded by appeals to (as yet unquantified and unquantifiable) probabilities for the existence of extraterrestrial intelligent life than I am for similar claims made about the purported improbability of the universe arriving at its present state, with humanity evolving on Earth, by chance (by which some would argue so-called 'intelligent design" is a reasonable alternate hypothesis to all that “science” stuff).
I do not believe in the existence of a god because I have been presented with no evidence of any god’s existence.
I do not believe in the claims of intelligent design or creationism, as opposed to evolution and mainstream cosmology, because I have been presented with no evidence of the truth of the former claims, while the latter is at present best supported by the currently available evidence, and like all scientific claims subject to revision as evidence or understanding of evidence develops over time.
I do not believe in the existence of extraterrestrial intelligent life because no evidence of such life has been presented. The difference here (contrasted against god, creationism, and so-called “intelligent design”) being that, at the very least, the proposition is grounded in the natural world and can be explored as a proper scientific hypothesis, subject to conventional standards of evidence and good old methodological naturalism, no appeal to the supernatural required or implied. It can and should be evaluated on par with the theory of evolution and big bang cosmology. Which requires that we withhold belief until such time as the evidence arises to warrant such a belief. The evidence is there for evolution and the big bang. It is not there yet for intelligent life elsewhere in the universe.
And, if somebody did build one, it would become “home” and the inhabitants would probably lose interest in colonizing planets – the only reason to travel to another solar system would be scientific curiosity and picking up raw materials.
If we’re talking about an interstellar generation ship… well, yes, you’re traveling with a farm (as part of a stable closed ecosystem). If we’re talking about one the size of even a small asteroid, having enough shielding to keep cosmic radiation down to a tolerable level and spinning it for gravity are trivial compared to the larger engineering issues of moving it at even a few percent of lightspeed.
The difference is that we know the creation of intelligent life in our universe is possible because we exist. With ~1025 chances for it to be created elsewhere, I’m confident that it does.
We don’t know if the creation of gods is possible, because we don’t have proof of any existing. You can have infinite chances for gods to be created, but if they can’t exist, we’ll still have none.
In my mind, the big filter is whether something can exist. The probability of it existing is just a numbers game.
Well, the Fermi Paradox is not some sort of logical argument against the existence of other civilizations in our galaxy, it is simply the observation that we do not see them. If you think it is, then you are going about this entire thing completely wrong.
But, further from that, your “solution” is not even close to reasonable, it is far fetched and bears no insight into the issue here.
But that solution has to apply 100% of the time, to every civilization and to every group, and even to every individual of every civilization that has ever existed in the galaxy.
But your method of doing so is non-logical. You now have to come up with an explanation as to why every single one of these civilizations would follow the path you have laid out for them.
It’s not really that simple of a notion, and treating it as though it is may be one of the issues you are running into.
Yes, you can in fact concoct all sorts of solutions, and that’s exactly what you are doing, concocting solutions, not basing anything on actual evidence.
The Earth was more or less completely covered in algae for a while. But, as far as limiting factors, those are space, resources, competition and predation. Assuming that there are no other space faring civs out there to compete with or prey on us, that leaves us to consume all the space and resources for ourselves.
If there are other space faring civs to compete or prey on us, then where are they?
We can look out and see. And what we see is no limit of space or resources. I may be basing my position on speculation, but it’s speculation based on what we know about life, technology, and the potential future of our species. You are also speculating, but you are speculating based on what ideas you think you can come up with that “refute” what we know, not based on what we actually do know.
The evidence for a filter is that the galaxy is not packed full of space faring civs. Something had to prevent them from doing so. That something is a filter. If you choose a different term for it, then sure you are free to do so, but it would still mean the same thing.
That’s what a filter is.
That’s actually not how poker works, at all. But, in any case, yes, there is a giant risk that everyone has to face, at some point, every player goes all in at least once.
Poker is also competition, where there can be only one winner, which is completely unrelated to evolution, where each instance is independent of each other, and you could have all winners.
So, terrible analogy. If you really want to use a card game analogy, try Solitaire. First one to win gets the galaxy. BTW, not all decks contain all the cards, sorry.
That’s exactly what the filter is. I have no idea what you are doing here at this point, doubting a concept, and then explaining the validity of that very same concept.
The implication of a great filter ahead of us is not based on the Fermi Paradox, but based on our chances of wiping ourselves out through nuclear war, climate change, bioengineered plague, or some other crazy way someone can think of to wipe us all out, things that are real possibilities as we look at the world around us. That then informs back into the Fermi Paradox as a possible explanation as to what happened to everyone else. If things were all rosy here on Earth, then we probably wouldn’t even speculate about such a possibility.
IOW, your refutation is against your misunderstanding of the great filter hypothesis, where you have it exactly backwards.
Right, and there could be unicorns that shoot down any space ships that try to leave the solar system.
You invoke a galactic federation that enforces migration controls on the entire galaxy, there’s no way we wouldn’t see some evidence of this. Other civs out there competing that we could run into would mean that there are other civs that would have run into us by now. I’m sure you can come up with tons of “what-if’s” to explain our lack of evidence of other spacefaring life out there, but the quality so far has been severely lacking, and I have no real reason to believe that your others would be any more based on what we know about the universe, rather than shoehorned as an attempt to “refute”.
Question, do you think that we will colonize the Moon and asteroids? I seem to remeber you were on that side of the debate. If not, then I guess that answers that question, but I’d be curious as to why you think not.
If you do think that we will colonize the Moon and asteroids, what do you think will make us stop expanding and colonizing more and more asteroids? What makes you think that we will be limited and content with the rocks that are here in our solar system?
There’s a bit in there I’d agree with, but you seem to be implying something that I did not say. I have no reason to think that they would move on, just expand. You seem to be implying that they abandon what they have built already, which they wouldn’t, any more than we abandoned New York as settlers expanded out from the city.
Yes. Probably mostly hydroponics and vertical farming, but there would be plenty of land for traditional farming as well.
I am not ignoring them, I addressed them. If you dig down into a asteroid, you are protected from radiation. If you build your base as a rotating habitat, you get gravity.
That have solutions that have already been presented.
What limitations would those be?
If we can fill up a solar system, then what stops us from continuing on to the next?
Actually, in tournaments, the rules do change over time. The antes and blinds go up as it progresses, making it harder and harder to stay in. Ironically, the rules of the universe are probably more or less the opposite, making it more and more likely for intelligent life to emerge as time progresses. (assuming of course that the first life to emerge doesn’t actively prevent others from doing so.)
Someone has to be first. And whoever is first would see a universe much like we see it. Whoever is first would also doubt the odds, and not think themselves lucky enough to be first, and desperately try to either find evidence of other civs, or come up with ad hoc explanations as to why they don’t see them.
Assuming that we don’t wipe ourselves out, the next intelligence to arise, assuming we allow them to do so, will see a vastly altered universe when they look out at the stars.
Slight difference. I have been presented with no evidence of any god’s existence, so I believe in no gods. I have been presented with evidence of intelligent life, so I believe in that. Intelligent life, unlike gods, does in fact exist in the universe, so it’s a question of how common it is, not whether or not it exists at all.
Yes, which is why the idea of habitable planets is unnecessary, the only use for them would be scientific curiosity. If we found another world with life on it, no matter how similar or different from us, it would be a gold mine of scientific inquiry on the creation and evolution of life.
OTOH, you say raw materials as an offhand comment, but that is exactly the entire reason for expansion in the first place, to gain raw materials.
You don’t have to move at a few percent lightspeed. As you say, you got your whole home with you, you’re in no real hurry. As long as you have enough thorium or hydrogen to power your reactors, you’re good, and the supplies on even a modest asteroid should hold out for hundreds of thousands, if not millions of years.
I can see colonizing something way out in the Oort Cloud. You (as a community, or a hive or computer mind) decide you want to go to another solar system. So you build up giant engines that are going to throw away a significant portion of your mass over a short period of time, and then point yourself at the Sun. Pass as close by it as you dare, and fire off your engines there, getting a nice boost from the Oberth effect. That won’t get you to a few percent of the speed of light, but it may get you to a tenth of a percent or so of the speed of light. Fast enough to get to nearby stars in hundreds of years.
Hmm. Traditional farming is very space-, water- and energy-intensive. I think that most food in the far future will be bioprinted from cellular tissue vats, or converted from vat-grown material in some other way. You’d only really have enough room to farm ‘traditionally’ on the largest megastructures, or on the surface of particularly hospitable planets - and I expect even ‘traditional’ farming will be unrecognisable to our eyes by that time.
All that does is allow me to grant that the existence of life elsewhere is a scientific hypothesis, subject to eventual proof. It does not itself establish proof, or even warrant a belief, particularly where the number of chances for an event to occur is essentially irrelevant until such time as someone can actually affix a probability on that event occurring.
Intelligent life either does, or does not, exist somewhere in the universe besides Earth. Probability really has nothing to do with it until such time as we have actual data to affix a probability on. That would entail not mere supposition about the possibility of life arising on Earth or elsewhere, but actual evidence of life observed elsewhere in the Universe, or failing that, a much better model of the probability of life arising anywhere than we currently have.
The time to believe is when evidence is presented, not before, and especially not when people seem to want to conflate probability with mere hypothetical possibility.
ETA: I mean, without knowing anything about me, even absent an assertion on my part, you might posit that there is a very good probability that I own a home with a garage and there is a car in it. Not an invisible dragon, mind you, just a plain old ordinary car. But until such time as you actually have evidence of me owning a home with a garage and a car in it, you have no reason to believe such a state of affairs exists. It’s not “kooky” to withhold a belief absent even an assertion on my part (the most mundane form of evidence I could imagine) that such a state of affairs exists. Never mind that we have lots of examples (certainly way more than one example, as we do with planets sustaining intelligent life in the universe at this moment) of other people owning homes with garages and cars.
That’s a more specific prediction than is being made. Nobody is pointing at a particular star and stating that there is a very good probability that there is life nearby. It’s instead a more general argument that there is likely to be found life elsewhere, wherever that may be. To use your analogy, it’s the more general “based on the existence of my home with a garage containing a car, I bet there’s another such arrangement out there.”
And I must disagree that there is literally no evidence of life out there; to the contrary, a belief in other life is buoyed by evidence that the conditions for life exist elsewhere. At its most basic level, we’ve determined that those lights in our night sky are stars like our sun. Taking this to a more advanced level, scientists have begun to pinpoint those particular stars that are the same type as our own sun, and have now started to catalogue planets. I think this, coupled with other research into biological processes, do provide a basis to develop the hypothesis of other life.
Is it a proven hypothesis? Of course not. But it’s hardly indefensible.
(my bolding)
The clarity of our vision remains an assumption. We’re definitely improving our ability to see elsewhere, but I doubt we’ve reached a peak.
And, the nature of deep space means we must account for the fact that we are looking backwards in time when we survey our neighborhood. If, when you look through your telescope, the fact that you don’t see any cars, or any lights on, or anything being delivered, could be because you are seeing your neighbors as they appeared thousands of years ago, before they laid down roads, built single family residences, and started making Amazon orders.
