If there is no multiverse and the coin flip is simply deterministic—perhaps based of the parity of the quadrillionth digit of pi—there is no version of AIXI that will benefit from paying the mugger, but it is still advantageous to precommit to doing so.
That seems to be a pretty counter-factual premise, though. There’s pretty good evidence for a multiverse, and you could hack AIXI to do the “right” thing—by giving it a “multiverse-aware” environment and utility function.
“No multiverse” wasn’t the best way to put it. Even in a multiverse, there is only one value of the quadrillionth digit of pi, so modifying AIXI to account for the multiverse does not provide a solution here, since we get the same result as in a single universe.
I don’t think multiverse theory works like that. In one universe it will be the 1001th digit, in another it will be the 1002th digit. There is no multiverse theory where some agent is presented with a problem involving the quadrillionth digit of pi in all the universes.
Once AIXI is told that the coin flip will be over the quadrillionth digit of pi, all other scenarios contradict its observations, so they are ruled out and the utility conditional on them stops being taken into account.
Possibly. If that turns out to be a flaw, then AIXI may need more “adjustment” than just expanding its environment and utility function to include the mulltiverse.
Uncomputable AIXI being “out-thought” by uncomputable Omega now seems like a fairly hypothetical situation in the first place. I don’t pretend to know what would happen—or even if the question is really meaningful.
I don’t think multiverse theory works like that. In one universe it will be the 1001th digit, in another it will be the 1002th digit. There is no multiverse theory where it is the quadrillionth digit of pi in all the universes.
That seems to be a pretty counter-factual premise, though. There’s pretty good evidence for a multiverse, and you could hack AIXI to do the “right” thing—by giving it a “multiverse-aware” environment and utility function.
“No multiverse” wasn’t the best way to put it. Even in a multiverse, there is only one value of the quadrillionth digit of pi, so modifying AIXI to account for the multiverse does not provide a solution here, since we get the same result as in a single universe.
I don’t think multiverse theory works like that. In one universe it will be the 1001th digit, in another it will be the 1002th digit. There is no multiverse theory where some agent is presented with a problem involving the quadrillionth digit of pi in all the universes.
Once AIXI is told that the coin flip will be over the quadrillionth digit of pi, all other scenarios contradict its observations, so they are ruled out and the utility conditional on them stops being taken into account.
Possibly. If that turns out to be a flaw, then AIXI may need more “adjustment” than just expanding its environment and utility function to include the mulltiverse.
I’m not sure what you mean. Are you saying that you still ascribe significant probability to AIXI paying the mugger?
Uncomputable AIXI being “out-thought” by uncomputable Omega now seems like a fairly hypothetical situation in the first place. I don’t pretend to know what would happen—or even if the question is really meaningful.
Priceless :-)
I don’t think multiverse theory works like that. In one universe it will be the 1001th digit, in another it will be the 1002th digit. There is no multiverse theory where it is the quadrillionth digit of pi in all the universes.