I do no more believe that Freedman P/NP paper shows that some
Quantum Universal machine can compute more than Deutsch QUM,
or, consequently, more than any Turing Universal Machine.
(Nor do Freedman himself, see
http://arxiv.org/abs/quant-ph/?0001071
)
About Calude attempts to go beyond the Turing barrier, I should
reread his paper, but from quant-ph/?0001071, it seems
that Calude machine cannot be implemented with an anyonic
quantum machine, making hard to believe Calude machine can
exist in some concrete way. But this deserves more thinking.
Note that this *is* good for the conceptual classical Church thesis
(if something like that was needed!)
Bruno
Received on Tue Oct 29 2002 - 03:59:42 PST