Sujet : Re: Cantor Diagonal Proof
De : news.dead.person.stones (at) *nospam* darjeeling.plus.com (Mike Terry)
Groupes : comp.theoryDate : 04. Apr 2025, 02:41:09
Autres entêtes
Message-ID : <7EKdnTIUz9UkpXL6nZ2dnZfqn_ednZ2d@brightview.co.uk>
References : 1
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On 03/04/2025 23:18, Lawrence D'Oliveiro wrote:
The Cantor diagonal construction is an algorithm for computing an
incomputable number.
It is not an algorithm for computing something. Algorithms are instructions that operate on finite inputs and must terminate with an answer at some point for every input.
Also, the number defined by the diagonal construction may or may not be computable, depending on the list to which it is applied. (In the technical sense of "computable numbers" as Turing used the term.)
<
https://en.wikipedia.org/wiki/Computable_number>
Regards,
Mike.
But if there is an algorithm for computing the number, then it is by
definition a computable number.
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