Re: Turing vs math

From: Jacques M. Mallah <jqm1584.domain.name.hidden>
Date: Mon, 25 Oct 1999 14:32:39 -0400 (EDT)

On Sun, 24 Oct 1999 hal.domain.name.hidden wrote:
> That is the argument. The hole is that it does not work if we consider
> one of the shortest possible universe programs, the universal dovetailer
> (UD). This simple program creates, as part of its output, flying rabbits.
> Yet it is an incredibly simple program, hence it is very high probability.
> In fact, it is very likely that we do live in the universe created by
> this program, and since that universe has flying rabbits in it we have
> failed to explain why we don't see flying rabbits.

        Simple. The UD itself generates all programs, so the measure
distribution within the UD-program will be rather similar to the overall
distribution. It's the same argument. The shorter UD'd programs will
contribute more to the measure. Within the UD, flying rabbit
sub-universes will be less common than simple subuniverses.
        While the UD is obviously not a problem, the problems I mentioned
before obviously have not been solved, namely the measure problem.
        As long as I'm posting I might as well mention that I agree with
Alistair Malcolm that Turing machines are not enough. Yes, a Turing
machine can simulate a continuous universe, but it can not BE a continuous
universe. (For example.) A continuous structure is a perfectly good
mathematical structure, but no Turing based scheme can include it. And
that's regardless of whether it is computable.

                         - - - - - - -
              Jacques Mallah (jqm1584.domain.name.hidden)
       Graduate Student / Many Worlder / Devil's Advocate
"I know what no one else knows" - 'Runaway Train', Soul Asylum
            My URL: http://pages.nyu.edu/~jqm1584/
Received on Mon Oct 25 1999 - 11:41:02 PDT

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