Liste des Groupes | Revenir à cs raspberry-pi |
On Mon, 30 Sep 2024 23:16:21 +0100, Pancho wrote:Well ordered is a text book definition, an important one in maths. Not a particularly "well" named one, as people do tend to confuse the meaning with total ordering. It should also be known in computer science, as the assumption that the positive integers are well ordered is equivalent to the assumption that induction works and induction is a similar concept to recursion.
On 9/30/24 23:06, Lawrence D'Oliveiro wrote:You were the one who used the term “well ordered”, and then said that,>No they aren't, precisely because the don't have a least integer.
On Mon, 30 Sep 2024 22:45:45 +0100, Pancho wrote:
>One assumes time is well ordered, so even if I don't know what the>
least century is, I know there was one.
Integers are well ordered, but there is no least integer.
>
>
Perhaps you are confusing having a total ordering with well ordered?
because of this, there had to be a least century.
Well, possibly. In banking software we assumed time was totally ordered, (but times from different clocks wasn't). In GPS software I don't know. In general, given we are all terrestrial observers, I'm not sure relativity matters, when discussing centuries. I'm not a physicist.Einstein’s Special Relativity says time is not totally ordered,All we want, I think, is a zero point far enough back that there is>
less real-world need to deal with negative time points.
That is basically what well-ordered implies. Obviously I was
bullshitting as I have no idea if time is totally-ordered, let alone
well ordered :-).
unfortunately ...
Les messages affichés proviennent d'usenet.