Imagine an extremely powerful computer in another universe that runs a vast number of simulations of our universe, enough so that someone with exactly your current brain state appears billions of times. I think you could use Katja’s argument to show that most of the time the civilization you belong to is doomed.
I guess you are confusing our universe with parallel worlds. It is very doubtful that there is a planet with the same geography and processes of evolution that completely replicated ours (even giving that evolution on Earth is the only way for life to emerge) so that there are ET humans who named one of their countries USA. So it is obvious that no one up there could share completely same experiences with us
Sorry, I’m not seeing it. Could you spell out how?
I agree that allowing simulation arguments changes the ball game. For instance, sim args favor universes with lots of simulated copies of you. This requires that at least one alien civilization develops AI within a given local region of the universe, which in turn requires that the filters can’t be too strong. But this is different from Katja’s argument.
To simplify things imagine that before you think about the Fermi paradox you calculate that we are in one of four types of universes:
In (A) civilizations frequently reach our level of development and then survive for a long time. In (B) civilizations frequently reach our level of development but then quickly get destroyed. In (C) civilizations rarely reach our level of development but if they do they survive for a long time. In (D) civilizations rarely reach our level of development but get quickly destroyed if they do. You assign some probability to our universe being in (B) or (D) (i.e. we are doomed).
Then you think about the Fermi paradox and realize that it drastically reduces the odds we are in (A), and this causes you to update thinking it more likely that we are in (B) or (D). Then you realize that since more brains like yours exist in (B) then (C), we are in big trouble.
Thanks! I think this is basically a restatement of Katja’s argument. The problem seems to be that comparing number of brains like ours isn’t the right question. The question is how many minds are exactly ours, and this number has to be the same (ignoring simulations) between (B) and (C): namely, there is one civilization exactly like ours in either case.
So if eternal inflation were correct and there were a vast number of universes, many corresponding to (A), (B), (C), and (D) with many minds exactly like yours in each then you would accept Katja’s argument?
Not sure of the relevance of eternal inflation. However, I think I’ve realized where my argument went astray and have updated the post accordingly. Let me know if we still disagree.
Imagine an extremely powerful computer in another universe that runs a vast number of simulations of our universe, enough so that someone with exactly your current brain state appears billions of times. I think you could use Katja’s argument to show that most of the time the civilization you belong to is doomed.
I guess you are confusing our universe with parallel worlds. It is very doubtful that there is a planet with the same geography and processes of evolution that completely replicated ours (even giving that evolution on Earth is the only way for life to emerge) so that there are ET humans who named one of their countries USA. So it is obvious that no one up there could share completely same experiences with us
If the many-worlds interpretation of quantum physics is true then there are lots of universes really, really similar to ours.
Yes, but the Fermi paradox and Great Filter operate within a given branch of the MWI multiverse.
That is a simulation style argument that is excluded at the top.
Sorry, I’m not seeing it. Could you spell out how?
I agree that allowing simulation arguments changes the ball game. For instance, sim args favor universes with lots of simulated copies of you. This requires that at least one alien civilization develops AI within a given local region of the universe, which in turn requires that the filters can’t be too strong. But this is different from Katja’s argument.
To simplify things imagine that before you think about the Fermi paradox you calculate that we are in one of four types of universes:
In (A) civilizations frequently reach our level of development and then survive for a long time. In (B) civilizations frequently reach our level of development but then quickly get destroyed. In (C) civilizations rarely reach our level of development but if they do they survive for a long time. In (D) civilizations rarely reach our level of development but get quickly destroyed if they do. You assign some probability to our universe being in (B) or (D) (i.e. we are doomed).
Then you think about the Fermi paradox and realize that it drastically reduces the odds we are in (A), and this causes you to update thinking it more likely that we are in (B) or (D). Then you realize that since more brains like yours exist in (B) then (C), we are in big trouble.
Thanks! I think this is basically a restatement of Katja’s argument. The problem seems to be that comparing number of brains like ours isn’t the right question. The question is how many minds are exactly ours, and this number has to be the same (ignoring simulations) between (B) and (C): namely, there is one civilization exactly like ours in either case.
So if eternal inflation were correct and there were a vast number of universes, many corresponding to (A), (B), (C), and (D) with many minds exactly like yours in each then you would accept Katja’s argument?
Not sure of the relevance of eternal inflation. However, I think I’ve realized where my argument went astray and have updated the post accordingly. Let me know if we still disagree.