I seriously believe that the expansion speed of (expanding) civilizations goes through a fast phase transition from 0 to c. I half-seriously believe that this is the proper explanation of the Fermi Paradox: we can’t observe other civilizations because they are approaching us with the speed of light. (And when finally we could observe them, they already turned us into computronium.)
I think this argument has the same logic as the Doomsday Argument, and therefore is subject to the same counterarguments (see SIA and UDT). I’ll explain the analogy below:
In the DA, the fact that I have a low birth rank is explained by a future doom, which makes it more likely for me to observe a low birth rank by preventing people with high birth ranks from coming into existence.
In your argument, the fact that we are outside the lightcones of every alien civilization is explained by the idea that they expand at light speed and destroy those who would otherwise observe being in the lightcone of an alien civilization.
I am afraid the analogy is not clear enough for me to apply it, and explicitly reproduce the relevant version of the counterarguments you are implying. I would be thankful if you elaborated.
In the meanwhile, let me note that the Doomsday argument floats in an intellectual vacuum, while my proposed 0-1 law for expansion speed could in principle be a proven theorem of economics, sociology, computer science or some other field of science, instead of being the wild speculation what it is. My goal to understand the physics of optimally efficient computational processes is motivated by exactly this: I wish to prove the 0-1 law, from still very speculative and shaky, but at least more basic assumptions.
I see, your proposed argument isn’t directly analogous to the standard Doomsday Argument, but more like a (hypothetical) variant that gives a number of non-anthropic reasons for expecting doom in the near future, and also says “BTW, a near future doom would explain why we have low birth rank.”
I’m not sure that such anthropic explanations make sense, but if you’re not mainly depending on anthropic reasoning to make your case, then the counterarguments aren’t so important.
BTW, I agree it is likely that alien civilizations would expand at near the speed of light, but not necessarily to finish some computation as quickly as possible. (Once you’re immortal, it’s not clear why speed matters.) Another reason is that because the universe itself is expanding, the slower those civilizations expand, the less mass/energy they will eventually have access to.
I think this argument has the same logic as the Doomsday Argument, and therefore is subject to the same counterarguments (see SIA and UDT). I’ll explain the analogy below:
In the DA, the fact that I have a low birth rank is explained by a future doom, which makes it more likely for me to observe a low birth rank by preventing people with high birth ranks from coming into existence.
In your argument, the fact that we are outside the lightcones of every alien civilization is explained by the idea that they expand at light speed and destroy those who would otherwise observe being in the lightcone of an alien civilization.
I am afraid the analogy is not clear enough for me to apply it, and explicitly reproduce the relevant version of the counterarguments you are implying. I would be thankful if you elaborated.
In the meanwhile, let me note that the Doomsday argument floats in an intellectual vacuum, while my proposed 0-1 law for expansion speed could in principle be a proven theorem of economics, sociology, computer science or some other field of science, instead of being the wild speculation what it is. My goal to understand the physics of optimally efficient computational processes is motivated by exactly this: I wish to prove the 0-1 law, from still very speculative and shaky, but at least more basic assumptions.
I see, your proposed argument isn’t directly analogous to the standard Doomsday Argument, but more like a (hypothetical) variant that gives a number of non-anthropic reasons for expecting doom in the near future, and also says “BTW, a near future doom would explain why we have low birth rank.”
I’m not sure that such anthropic explanations make sense, but if you’re not mainly depending on anthropic reasoning to make your case, then the counterarguments aren’t so important.
BTW, I agree it is likely that alien civilizations would expand at near the speed of light, but not necessarily to finish some computation as quickly as possible. (Once you’re immortal, it’s not clear why speed matters.) Another reason is that because the universe itself is expanding, the slower those civilizations expand, the less mass/energy they will eventually have access to.