Sujet : Re: More complex numbers than reals?
De : james.g.burns (at) *nospam* att.net (Jim Burns)
Groupes : sci.mathDate : 15. Jul 2024, 18:04:41
Autres entêtes
Organisation : A noiseless patient Spider
Message-ID : <04ee3223-9d81-4e2d-bc17-7883ce5dc2ca@att.net>
References : 1 2 3 4 5 6 7 8 9 10 11
User-Agent : Mozilla Thunderbird
On 7/15/2024 9:26 AM, WM wrote:
Le 15/07/2024 à 00:39, Ben Bacarisse a écrit :
[...]
>
The only daredevil who tried it, Jim Burns,
has to assume that
by exchangig one of the elements can disappear.
Assume that ℕⁿᵒᵗᐧᵂᴹ is the set of finiteⁿᵒᵗᐧᵂᴹ ordinals.
If α is finiteⁿᵒᵗᐧᵂᴹ, then α⁺¹ = α∪{α} is finiteⁿᵒᵗᐧᵂᴹ.
If α ∈ ℕⁿᵒᵗᐧᵂᴹ, then α⁺¹ ∈ ℕⁿᵒᵗᐧᵂᴹ.
f(α) = α⁺¹ is 1.to.1
¬∃β≠α: β⁺¹ = α⁺¹
f: ℕⁿᵒᵗᐧᵂᴹ → ℕⁿᵒᵗᐧᵂᴹ\{0}: 1.to.1
ℕⁿᵒᵗᐧᵂᴹ ∋ 0 ∉ f(ℕⁿᵒᵗᐧᵂᴹ)
'Bye, Bob!
No reason to pay attention.
E pur si muove.