[FOM] Re: On physical Church-Turing Thesis

[Eric Baum]

Warren D. Smith wrote two relevant papers. In the first,
if I recall correctly, he showed that for n bodies interacting
under Newtonian gravity, he could construct an orbit that
was not simulable by a Turing machine, although if he added
in some relativistic effects, the Church-Turing thesis held
again.

In the second, he showed the Church-Turing thesis is true in
nonrelativistic quantum mechanics with sufficiently nice potentials.

Church's thesis meets the n-body problem:
http://citeseer.nj.nec.com/77650.html

Church's thesis meets quantum mechanics:

http://citeseer.nj.nec.com/smith99churchs.html

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