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Douglas_Knight comments on Crazy Ideas Thread - Less Wrong Discussion
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Since quantum mechanics is true, Deutsch self-consistency has pretty big advantages over Novikov self-consistency.
Good point. I may be thinking about this wrong, but I think Deutsch self-consistent time travel would still vastly concentrate measure in universes where time travel isn't invented, because unless the measures are exactly correct then the universe is inconsistent. Whereas Novikov self-consistent time travel makes all universes with paradoxes inconsistent, Deutsch self-consistent time travel merely makes the vast majority of them inconsistent. It's a bit like quantum suicide: creating temporal paradoxes seems to work because it concentrates your measure in universes where it does work, but it also vastly reduces your total measure.
That's why it's not usually called "Deutsch self-consistency." It's not supposed to be a filter on legal universes, but a dynamic rule that each initial condition does lead to a consistent universe. The resolution of the grandfather paradox is a 50-50 superposition of the universe where you are born and leave and the universe where you appear, kill your grandfather, and are never born. You could say that it filters out the 80-20 superposition, but that's like saying that Newton's self-consistency principle filters out universes that don't obey his laws. (Well, maybe that's Lagrange's self-consistency principle...)