this post was submitted on 29 Jun 2024
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So if they are right, the Earth is incredibly rare and would be a great find for space faring civilizations. They also had plenty of time to pass by and find this incredibly rare life bearing sphere. But they didn't. You can flip things how ever you want, the question remains - why haven't we seen anyone?
It's simple. We're the first intelligent life in the galaxy. There is nobody else yet in our galaxy.
Also, probably nobody capable of traveling the stars wants to settle a planet. Once you figure out how to make huge spaceships (which you'll need to travel interstellar space) you've essentially learned how to make cities in space. Our solar system would support a lot of people if we just used the resources available for space habitats, and by "lot" I mean in the quadrillions. And it turns out that all you need to support that population is a star to provide energy, and some planets to source materials from.
So with that in mind, why bother finding another habitable planet?
The thing is, out of a population of trillions (or even quadrillions as you say), you only need a few thousand to travel to the stars to colonize another planet. With how large the population is, that is bound to happen. Just like there were bound to be pioneers travelling to the new world to settle it, despite how dangerous the journey was. And how there will be pioneers to settle the moon or mars or further out.
And a civilization like that would absolutely send stuff to other star systems, if only for science, so most of the research for the journey would already be done. And this is assuming that a civilization wouldn't want ever greater quantities of resources for ever greater projects, or access to other star systems for reasons we cannot fathom today (maybe neutron stars or black holes have some incredibly tempting uses? Or maybe there's some useful resources out in the galaxy that we have yet to discover?)
Basically, a successful civilization like that is bound to spread out, it's difficult to see scenarios where a successful civilization would be so homogenous in thought as for that to not happen. Amd then it's before we even get to sending AI probes to "colonize" space and gather data.
I don't think it is a valid point. Yeah, if we can build a ship that take us to Alpha Centauri it would lool like a small city, but that does not mean that it can last forever and the traveller would never need to settle on a planet. And looking what the humans did in the past, it seems logic that while a part would want to continue to explore, another part would want to settle on a planet.
Because it is habitable and can be used as a transit point, advanced outpost, refuelling base or any other use you can do of an habitable planet where to do things you have not to fight even with the environment (tourism for example).
Or there are plenty of societies at least as advanced as we are, but we can't find each other because space is big and our stars tend to drown out our own puny EM emissions.
Yeah agreed, there's no way we're picking up alien radio broadcasts, not over the noise produced by a star.
On the other hand, if a civilization were creating a Dyson sphere, or other large constructions, we'd be able to see those unusual elements in the light spectrum coming off the star. So it is conspicuous that we haven't seen anything like that.
There's a fair question of "would it ever be practical to do such large constructs". As far as energy capture, between advances in energy efficiency and solar capture, one could imagine having energy beyond our greatest ambitions with no or minimal space based solar energy collection. The resources involved to construct such a thing would involve a mass equivalent to an entire planet to make a super thin shell, and we'd want to be pickier than just any old matter.
Similar to people dreaming of Mars colonization as a workaround for climate change. Anything we could do to make Mars livable would be even harder than engineering Earth's climate. Now maybe population growth may demand more area one day, or non replacement birth rates become so normal that population just starts shrinking.
There is the possibility that no one can "win" against the physics, and things didn't get much more advanced in space for any species than they are today for us. If that's the case, then we shouldn't be surprised that other hypothetical civilisations cannot be found.
Suhweeet! We can be the Old Ones, Chutulu flatghn la!
They actually haven't had much time to pass by. Earths only been around for 4.6 billion years, a couple hundred million of that was spent being a cooling ball of magma. Space is fucking huge and the universe is still very young. It's very likely we are on the early end of the development of life in the universe. A lot of things had to happen before our complex life could evolve.
As you said, after the formation of Earth, it took only a few hundred milion years for life to develop. That is incredibly short, almost instanteneously as soon as conditions for life were met, life formed. Our galaxy, the Milky Way, formed almost as soon as galaxies could form. So here we have a situation where a inteligent civilization could have formed anywhere in our galaxy 13 bil years ago or at any point in time after that. Chance is, if they had, by now they would have conquered the whole galaxy. Absence of any sign of inteligent life can be wxplained by the Great Filter. It could be any of the following: 1) interstellar travel is never feasible for any civ, no matter how advanced, 2) Earth-like planets are so rare, that we are probably the only inteligent civ in our galaxy, 3) Earth-like planets are not that rare, but inteligent civs tend to destroy themselves before they manage to spread out to other planets... We don't know what the Great Filter is, but it must be pretty destructive for a civ. I just want to point out the fact that the Great Filter is probably still ahead of us and that we shouldn't take our existence for granted. We need to meticulously examine and neutralize any possible threats to human civilization. This is not fearmongering. It's just common sense, after you take all the facts into account that I laid out.
Actually life needs complex elements that only form in neutron star collisions(kilonovas) It could have been that the universe needed to be a couple billion years old before the elements that could create complex life actually came into existence. Everything else is pretty accurate, and I do think interstellar travel will end up being impossible, even terraforming other planets seems like it's a couple thousand years away.
As far as earth-like planets being rare, even if they are only 1 in 10,000 there would likely still be tens of millions in our galaxy alone.
I think 1 in 10k is way too common still. Somewhere between 1 in a billion to one in a trillion is more reasonable.
If there is a great filter...
I mean, as you said, we're pretty early to the scene. Why can't we be the first in this galaxy? Perhaps planets like earth aren't rare over the lifetime of a galaxy, but they are rare in these early years of a galaxy. In other words, earth just developed quickly, so now we're here before any other earth-like planets have had a chance to develop intelligent life.
I don't think that we are pretty early. Our galaxy already exists for so long, it's unfathomable. Yet, it seems to be empty and lifeless.
My mistake, I thought you had said something to that effect.
Well for what it's worth, we do seem to be early. Our sun appears to be among the first wave of "3rd generation stars" (stars that were born from the nebula of a supernova of a star that was born the same way, from another supernova). It's thought that only those 3rd Gen stars will have planets with enough heavy elements to support life. All elements heavier than iron [26] on the periodic table, can only be created naturally in a supernova.
So yeah, the theory is, if we're one of the first 3rd Gen stars out there in this galaxy, and if life formed on this planet basically as soon as it could have after the earth cooled enough, then we're probably early on the scene for life.
I like the idea behind the concept of the Great Filter, but that point does not seems logic as it would imply that irregardless of how advanced a civ is, they would not be able to build anything that can even make just a one way travel to a star just a few year light far away. Right, it is not simple, but a civ even just a couple centuries head of us should be able to do it.
My friend, that's exactly my point. That is, they've had enough time to show up but they are nowhere to be seen.
Wait a moment, maybe I understand wrong (English is not my first language) but I understand that you said that the Great Filter is the reason why we don't see them and point out 3 possible points.
I dispute your first point to be not really an explanation or an option since saying "never feasible for any civ, no matter how advanced" just seems to be a too harsh limit on what a civ could do, which looking at our past history seems an unreasonable limit.
Your point seems to be that since there is the Great Filter (btw, to be proven) then there is no one else out there.
You exclude way simpler possibillities like the option that a civ just a couple centuries ahead of use could already be colonizating the nearby stars, they just are 1000 LY away so we cannot yet see them (assuming we even know what to look for).
Maybe it's because we're not as evolved as we think. If aliens did appear, how many kooks would want to attack them because they are different?
If they land in one country, would other countries get jealous or scared, thinking that country now has an advantage? Shit, what happens if the neighbouring country had nukes; would they launch?
More likely is that if aliens had detected life here, Earth would be marked as a red, no-go zone, because of how unstable, tribal and violent we are.
Every conservative on earth would demand we attack the flying illegal aliens. Our planet's dumbest of dipshit right-wingers would be outside shooting at clouds all night long.
Maybe it's impossible to travel faster than the speed of light? So it may not be a thing where aliens can just swing by our solar system to snap a few photos before heading off to the next one.
I'm sure that's the case. You can travel to other stars without ftl, it's just a lot slower and probably one way. It's really pretty limiting for society, for instance, without ftl an interstellar "civilization" is basically out of the question, you can't govern another star system without at the very least faster communication.