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Re: How can we decide a function is undecidable?

From Ben Bacarisse <ben.usenet@bsb.me.uk>
Newsgroups comp.theory
Subject Re: How can we decide a function is undecidable?
Date 2021-08-31 15:09 +0100
Organization A noiseless patient Spider
Message-ID <87v93l3du0.fsf@bsb.me.uk> (permalink)
References <e1ab661d-68e6-4a75-8bcf-0e0922f552f5n@googlegroups.com> <9261dafe-7a7c-4246-b43b-2d46d0b49b21n@googlegroups.com> <a46fc03b-a0ee-4de9-a577-972427717e6fn@googlegroups.com>

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wij <wyniijj@gmail.com> writes:

> On Tuesday, 31 August 2021 at 01:00:49 UTC+8, dklei...@gmail.com wrote:

>> A mathematical function is usually defined as a set of ordered pairs. 
>  
> "associating x to y" is a process. A hidden variable is 'time'.
> 'ordered pair' has no concept of time.

Yes, that's why the "function as a process" is not the one that's used.
The notation f: X -> Y means f is a subset of X x Y with the key
"function" property (that images are unique).

-- 
Ben.

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Thread

How can we decide a function is undecidable? wij <wyniijj@gmail.com> - 2021-08-30 09:20 -0700
  Re: How can we decide a function is undecidable? "dklei...@gmail.com" <dkleinecke@gmail.com> - 2021-08-30 10:00 -0700
    Re: How can we decide a function is undecidable? olcott <NoOne@NoWhere.com> - 2021-08-30 12:20 -0500
    Re: How can we decide a function is undecidable? wij <wyniijj@gmail.com> - 2021-08-31 02:26 -0700
      Re: How can we decide a function is undecidable? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-08-31 15:09 +0100
  Re: How can we decide a function is undecidable? olcott <NoOne@NoWhere.com> - 2021-08-31 08:44 -0500
    Re: How can we decide a function is undecidable? Richard Damon <Richard@Damon-Family.org> - 2021-08-31 18:52 -0400

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