this post was submitted on 29 Jun 2024
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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).