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: Thu, 19 Dec 2024 15:50:28 +0100 Organization: A noiseless patient Spider Lines: 45 Message-ID: References: <696c5a55-3cb6-4fa7-bd11-9b8f8eeeaef7@att.net> <3f902f42-e435-4a44-a179-687ad2a33f16@att.net> <4f0bc5b5-aba7-4c19-91f7-d4f9788591a0@att.net> <6c74c2e9-17d7-4eb4-afcd-c058309b6c8a@tha.de> <4327ba4a-e810-4565-83e8-b9572018ac35@att.net> <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: Thu, 19 Dec 2024 15:50:28 +0100 (CET) Injection-Info: dont-email.me; posting-host="b073b4606e4aae76152a468e84e37494"; logging-data="3043228"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX196aiLuvfIdJL6iAzC0VI64fkc7OGqVgVo=" User-Agent: Mozilla Thunderbird Cancel-Lock: sha1:0WJm7rB7/x1sQq3WrjRrzoSxbe8= Content-Language: en-US In-Reply-To: <31180d7e-1c2b-4e2b-b8d6-e3e62f05da43@att.net> Bytes: 3342 On 18.12.2024 21:21, Jim Burns wrote: > On 12/18/2024 2:14 PM, WM wrote: >> On 18.12.2024 19:22, Jim Burns wrote: >>> On 12/18/2024 7:40 AM, WM wrote: >>>> On 18.12.2024 02:16, Jim Burns wrote: > >>>>> The infinite end.segments of finite.cardinals >>>>> do not include any finite end.segments and >>>>> they have an empty intersection. >>>> >>>> Explicitly wrong. >>>> As long as >>>> only infinite endsegments are concerned >>>> their intersection is infinite. >>>> There are no limits involved. >>> >>> Then it would be great if you (WM) >>> stopped calling things 'limit sets' >> >> The sets described here are not limit sets. > > Q. What is a limit set? > >> f(k) = ∩{E(1), E(2), ..., E(k)} >> with E(1) = ℕ >> ∀k ∈ ℕ : >> ∩{E(1), E(2), ..., E(k+1)} = >> ∩{E(1), E(2), ..., E(k)} \ {k}, >> ∩{E(1), E(2), ...} is empty. >> Other sets are not in the argument. > > ∀k ∈ ℕ : > k ∉ E(k+1) ⊇ ⋂{E(1),E(2),...} ∌ k > > ⋂{E(1),E(2),...} is empty. But E(1) is full. The only way to get rid of content is to proceed by ∀k ∈ ℕ: ∩{E(1), E(2), ..., E(k+1)} = ∩{E(1), E(2), ..., E(k)} \ {k}, i.e. to lose one number per term of the function f(k) = ∩{E(1), E(2), ..., E(k)}. The empty term has lost all natnumbers one by one. Regards, WM