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From: ok@quintus.uucp (Richard A. O'Keefe)
Newsgroups: comp.ai
Subject: Re: The Ignorant assumption
Message-ID: <443@quintus.UUCP>
Date: 20 Sep 88 06:36:52 GMT
References: <1369@garth.UUCP> <2346@uhccux.uhcc.hawaii.edu> <1383@garth.UUCP> <372@quintus.UUCP> <1390@garth.UUCP> <388@quintus.UUCP> <7059@aw.sei.cmu.edu>
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Reply-To: ok@quintus.UUCP (Richard A. O'Keefe)
Organization: Quintus Computer Systems, Inc.
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In article <7059@aw.sei.cmu.edu> firth@bd.sei.cmu.edu (Robert Firth) writes:
>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?

If you will inspect the original posting, you will see that it was a
rhetorical question directed at a posting which said "if we assume that
the universe is a Turing machine ...".  My question was a polite way of
saying "I _won't_ assume that, so there".

>None whatever.  The conjecture is almost instantly disprovable: no Turing
>machine can output a true random number, but a physical system can.

Reference please!  This is a _staggering_ result!  I can believe that it
is true, but it is astonishing to learn that it has been _shown_.  (I
strongly suspect that Robert Firth has assumed here what he set out to
prove.)  How do you tell when "a true random number" has been output, anyway?