the probability that any given chunk of stuff is ‘you’ has to go to zero.
I don’t see why. If there’s an x% chance of a given chunk of stuff in universe U_1 being you, and there’s a 50% chance of universe U_1, then there should at least be an x/2% chance of a given chunk of stuff being you, right? And those calculations don’t actually use that it’s an exponential decrease. It could have been P(U_n) = 1/Σ(n) and it would still apply.
I’m not sure how you’re thinking of this, but think about what’s going on in jesscat’s “souls” toy picture. In order for U_n to be possible, there must be at least n souls. Since U_n exists for every n, there must be an infinite number of souls—and therefore zero chance that when we pick out exactly one soul for U_1, yours is the soul that gets chosen. Therefore, ‘your’ probability of existing in U_1 is 0.
This almost works like if each ‘soul’ was a configuration of a person, and you were one particular configuration—except U_n (and SIA) don’t specify that each person has to be unique. Instead, it’s more analogous to a particular configuration of a particular chunk of matter—that’s one way to put in uniqueness.
The vast majority of possible souls live in chaotic universes. Under this theory, rather than just having a random experience like a Boltzmann brain, you almost certainly have no experience. But having a sensible experience is still astronomically low.
I don’t see why. If there’s an x% chance of a given chunk of stuff in universe U_1 being you, and there’s a 50% chance of universe U_1, then there should at least be an x/2% chance of a given chunk of stuff being you, right? And those calculations don’t actually use that it’s an exponential decrease. It could have been P(U_n) = 1/Σ(n) and it would still apply.
I’m not sure how you’re thinking of this, but think about what’s going on in jesscat’s “souls” toy picture. In order for U_n to be possible, there must be at least n souls. Since U_n exists for every n, there must be an infinite number of souls—and therefore zero chance that when we pick out exactly one soul for U_1, yours is the soul that gets chosen. Therefore, ‘your’ probability of existing in U_1 is 0.
This almost works like if each ‘soul’ was a configuration of a person, and you were one particular configuration—except U_n (and SIA) don’t specify that each person has to be unique. Instead, it’s more analogous to a particular configuration of a particular chunk of matter—that’s one way to put in uniqueness.
The vast majority of possible souls live in chaotic universes. Under this theory, rather than just having a random experience like a Boltzmann brain, you almost certainly have no experience. But having a sensible experience is still astronomically low.