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From: firth@sei.cmu.edu (Robert Firth)
Newsgroups: comp.ai
Subject: Re: The Ignorant assumption
Message-ID: <7059@aw.sei.cmu.edu>
Date: 19 Sep 88 22:05:30 GMT
References: <1369@garth.UUCP> <2346@uhccux.uhcc.hawaii.edu> <1383@garth.UUCP> <372@quintus.UUCP> <1390@garth.UUCP> <388@quintus.UUCP>
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In article <388@quintus.UUCP> ok@quintus.UUCP (Richard A. O'Keefe) writes:

>But is there any reason to suppose that the universe _is_ a Turing machine?

None whatever.  The conjecture is almost instantly disprovable: no Turing
machine can output a true random number, but a physical system can.  Since
a function is surely "computable" if a physical system can be constructed
that computes it, the existence of true random-number generators directly
disproves the Church-Turing conjecture.