Postselection is the power of discarding all runs of a computation in which a given event does not occur.

PostBQP in particular is “post-selecting on a measurement yielding a specific outcome”.

If a quantum simulator has access to all amplitudes, at measurement time, why can’t it evaluate to one of the post-selected outcomes? Isn’t that the same as post-selection?

]]>It seems to work for your example of finding collisions.

]]>But the other issue is: should I actually acknowledge you in my paper as “Sniffnoy”? ๐ I’ll do it if I can use your real name.

]]>An ideal simulator would exactly match the power of a QC and nothing more.

It’s not efficient to simulate a QC using a PDQP or PostBQP machine.

That’s like using NP to simulate BPP.

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