[mshron]

One of Aaronson's arguments in the article boils down to the idea that running a full universe simulation (without cheating) on a universe with the same physics as ours may just not be possible computationally; it seems physically plausible that you need a universe to compute a universe.

If that's true, then the simulators would need to be running in a different kind of universe than ours... in which case "ancestor simulation" doesn't really make sense.

[303uru]

Well, yes, quantum physics says that's true. Our universe is the minimal requirements necessary to run our universe. There could be tricks, for instance maybe you only simulate at fine grain the universe near an observer. But still, to simulate our granularity you need a simulation of equal (or greater) granularity. There's the trick, it's conceivable that the simulator exists in a universe with more dimensionality.

[vagab0nd]

What if the simulation is the only thing in that universe?