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From: smryan@garth.UUCP (Steven Ryan)
Newsgroups: comp.ai.digest
Subject: Re: state and change/continuous actions
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Date: 26 Sep 88 06:01:00 GMT
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From: garth!smryan@unix.sri.com  (Steven Ryan)
Organization: INTERGRAPH (APD) -- Palo Alto, CA
Subject: Re: state and change/continuous actions
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>Foundations of Artificial Intelligence," I find it interesting to
>compare and contrast the concepts described in Chapter 11 - "State
>and Change" with state/change concepts defined within systems
>theory and simulation modeling. The authors make the following statement:
>"Insufficient attention has been paid to the problem of continuous
>actions." Now, a question that immediately comes to mind is "What problem?"

Presumably, they are referring to that formal systems are strictly discrete and
finite. This has to do to with `effective computation.' Discrete systems can be
explained in such simple terms that is always clear exactly what is being
done.

Continuous systems are computably using calculus, but is this `effective
computation?' Calculus uses a number of existent theorems which prove some
point or set exists, but provide no method to effectively compute the value.
Or is knowing the value exists sufficient because, after all, we can map the
real line into a bounded interval which can be traversed in finite time?

It is not clear that all natural phenomon can be modelled on the discrete
and finite digital computer. If not, what computer could we use?

>Any thoughts?