Path: ...!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail From: WM Newsgroups: sci.math Subject: Re: Incompleteness of Cantor's enumeration of the rational numbers (extra-ordinary) Date: Sat, 28 Dec 2024 15:03:44 +0100 Organization: A noiseless patient Spider Lines: 20 Message-ID: References: <4051acc5-d00a-40d2-8ef7-cf2b91ae75b6@att.net> <8d69d6cd-76bc-4dc1-894e-709d044e68a1@att.net> <7356267c-491b-45c2-b86a-d40c45dfa40c@att.net> <4bf8a77e-4b2a-471f-9075-0b063098153f@att.net> <31180d7e-1c2b-4e2b-b8d6-e3e62f05da43@att.net> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Injection-Date: Sat, 28 Dec 2024 15:03:44 +0100 (CET) Injection-Info: dont-email.me; posting-host="5d0ee4217b8db9d987b3a5f773aec09b"; logging-data="368274"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX1+IWNd9cPoNMidVhbIlz9eVEJXt9weFNZk=" User-Agent: Mozilla Thunderbird Cancel-Lock: sha1:55oo7j9n3iJYm6ryoneRyGdrJ58= In-Reply-To: Content-Language: en-US Bytes: 2505 On 27.12.2024 22:00, Jim Burns wrote: > On 12/27/2024 5:14 AM, WM wrote: >> They are invariable numbers like ω and ω+1. > > ω is > the set of (well.ordered) ordinals k such that > #⟦0,k⦆ ≠ #(⟦0,k⦆∪⦃k⦄) > (such that k is finite) That is one interpretation. My interpretation is Cantor's original one: ω is the limit of the sequence 1, 2, 3, ... . > A separate fact is that > ⟦0,ω⦆ ≠ ⟦0,ω⦆∪⦃ω⦄ [0, ω-1] = [0,ω⦆ = ℕ =/= [0, ω] Regards, WM