NetNews Usenet Archive 1992 #27/NN_1992_27.iso/spool/comp/specific/536

Text File | 1992-11-17 | 1.7 KB | 40 lines

Newsgroups: comp.specification
Path: sparky!uunet!ukma!darwin.sura.net!zaphod.mps.ohio-state.edu!cis.ohio-state.edu!seal.cis.ohio-state.edu!ogden
From: [e-mail] (William F Ogden)
Subject: Re: "Algebra": and Re: Semantic definition style
Message-ID: <[e-mail]>
Keywords: structural operational semantics, denotational semantics
Sender: [e-mail] (NETnews        )
Organization: The Ohio State University Dept. of Computer and Info. Science
References: <[e-mail]> <[e-mail]> <[e-mail]>
Date: Wed, 18 Nov 1992 01:47:00 GMT
Lines: 27

In article <[e-mail]> [e-mail] (victor yodaiken) writes:
   ...
>In any event, I've never been able to understand the virtue of working
>within a mathematical model of computation which permits description of
>processes that cannot be carried out, even in principle, by any physical
>computing device. What is it that one intends to learn by application of
>these methods?

If you look at recursion theory, you'll find that it has developed some
rather interesting results about degrees of unsolvability by just such an
approach.

From this work we know, for example, that natural numbers, a mathematical
domain which we often use to model computations, permit the description of
computations that can certainly not be carried out. In fact, in almost
every domain within which we can describe those computations that could be
carried out on a physical computing device, we can also describe processes
which could not. We don't have a choice here, the power to describe the
uncomputable just comes with the language that allows us to describe the
computable.



--

/Bill