Sorry, it seems I was too sloppy, I even must revise my opinion on Scott who seemed to represent a very reasonable point of view although (I agree with you) he tries to conform a bit too much for my taste as well.
Still, I have a very special intutitive suspicions with the WMI: if the physics is so extremely generous and powerful that it spits out all those universes with ease, why does not it allow us to solve exponential problems?
How comes that our world has such a very special physics that it allows us to constructs machines that are slightly more powerful than Turing machines (in an asymptotical sense) still not making exponential (or even NP-complete) problems tractable?
It looks like a strange twist of nature that we have this really special physics that allows us to construct computational processes in this very narrow middle ground in asymptotic complexity. Generating all those exponentially increasing number of universes, but does not allow their inhabitants to exploit them algorithmically to the full extent.
Can't it be that that our world still has to obey certain complexity limits and some of the universes have to be pruned away for some reason?
This is a fascinating way of looking at it.
My first thought was to reply, "Yes, most worlds may need to be pruned a la Hanson's mangled worlds, but that doesn't mean you can end up with a single global world without violating Special Relativity, linearity, unitarity, continuity, CPT invariance, etc."
But on second thought this seems to be arguing even further, for the sort of deep revolution in QM that Scott wants - a reformulation that would nakedly expose the computational limits, and make the ontology no more extravagant than the fastest comput...
Eliezer Yudkowsky and Scott Aaronson - Percontations: Artificial Intelligence and Quantum Mechanics
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