Path: utzoo!utgpu!water!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!mailrus!ames!lll-tis!lll-winken!arisia!quintus!ok 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> Sender: news@quintus.UUCP Reply-To: ok@quintus.UUCP (Richard A. O'Keefe) Organization: Quintus Computer Systems, Inc. Lines: 15 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?