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Path: ...!Xl.tags.giganews.com!local-1.nntp.ord.giganews.com!news.giganews.com.POSTED!not-for-mail NNTP-Posting-Date: Thu, 29 Aug 2024 22:46:02 +0000 Subject: Re: Replacement of Cardinality (infinite middle) Newsgroups: sci.logic,sci.math References: <hsRF8g6ZiIZRPFaWbZaL2jR1IiU@jntp> <v9926l$102t7$1@dont-email.me> <v993ip$10cor$1@dont-email.me> <v99e6j$1etn8$1@dont-email.me> <v9anp7$2o5mp$2@dont-email.me> <ad6dnanB9ZgbYyX7nZ2dnZfqnPSdnZ2d@giganews.com> <5f795e1a-346b-43f7-a2d2-7844591f5296@att.net> <-oGdnWXm-ZVn1iT7nZ2dnZfqn_ednZ2d@giganews.com> <11887364-602b-4496-8f37-aa6ec7d9f69c@att.net> <CQ2dnbEy6NxK6if7nZ2dnZfqn_adnZ2d@giganews.com> <2ce53910-5bb0-4ebd-805b-dccc0b21dc13@att.net> <u6Cdnbt99Z8lNSf7nZ2dnZfqn_GdnZ2d@giganews.com> <30967b25-6a7e-4a67-a45a-99f5f2107b74@att.net> <wdScnSnh-eTlnyH7nZ2dnZfqn_qdnZ2d@giganews.com> <58c50fcb-41ea-4ac3-9791-81dafd4b7a59@att.net> <Z1qdnZK14ptcl137nZ2dnZfqn_ednZ2d@giganews.com> <29fc2200-8ddc-43fe-9130-ea49301d3c5d@att.net> <bKGdnSJUP5vzn1_7nZ2dnZfqnPWdnZ2d@giganews.com> <1c5a8e0d-db33-4254-b456-8bb8e266c295@att.net> <wFadnSzMD4-A-1_7nZ2dnZfqnPqdnZ2d@giganews.com> <fe1ff590-228e-4162-b59d-5e66fadedfef@att.net> <jWSdneBt4MAqAV77nZ2dnZfqn_udnZ2d@giganews.com> From: Ross Finlayson <ross.a.finlayson@gmail.com> Date: Thu, 29 Aug 2024 15:46:19 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.6.0 MIME-Version: 1.0 In-Reply-To: <jWSdneBt4MAqAV77nZ2dnZfqn_udnZ2d@giganews.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Message-ID: <nP-dnd-rxey3Z037nZ2dnZfqnPednZ2d@giganews.com> Lines: 111 X-Usenet-Provider: http://www.giganews.com X-Trace: sv3-poX22WJlS4dkdGMksZeustb0TOn3P5ZRqYirEEfX64AZ0KXDLvNlCqdWx5LWdLmBDIUx5MDM9PWCVSC!tgrCY4KsmOprp0C5odeI0jjM+JBiUZXMP3Qn8xklwER9uobNQ966eRLJJBaWQxNFNvE2EI1CQAig X-Complaints-To: abuse@giganews.com X-DMCA-Notifications: http://www.giganews.com/info/dmca.html X-Abuse-and-DMCA-Info: Please be sure to forward a copy of ALL headers X-Abuse-and-DMCA-Info: Otherwise we will be unable to process your complaint properly X-Postfilter: 1.3.40 Bytes: 6174 On 08/19/2024 12:27 PM, Ross Finlayson wrote: > On 08/18/2024 09:56 PM, Jim Burns wrote: >> On 8/18/2024 5:22 PM, Ross Finlayson wrote: >>> On 08/18/2024 10:50 AM, Jim Burns wrote: >>>> On 8/18/2024 10:17 AM, Ross Finlayson wrote: >>>>> On 08/17/2024 02:12 PM, Jim Burns wrote: >> >>>>>> Lemma 1. >>>>>> ⎛ No set B has both >>>>>> ⎝ finiteᵖᵍˢˢ order ⟨B,<⟩ and infiniteᵖᵍˢˢ order ⟨B,⩹⟩. >>>>>> >>>>>> Definition. >>>>>> ⎛ An order ⟨B,<⟩ of B is finiteᵖᵍˢˢ iff >>>>>> ⎜ each non.empty subset S ⊆ B holds >>>>>> ⎝ both min[<].S and max[<].S >>>>>> >>>>>> A finiteᵖᵍˢˢ set has a finiteᵖᵍˢˢ order. >>>>>> An infiniteᵖᵍˢˢ set doesn't have a finiteᵖᵍˢˢ order. >>>>>> >>>>>> ℕ ℤ ℚ and ℝ each have infiniteᵖᵍˢˢ orders. >>>>>> In the standard order, >>>>>> ℕ ℤ ℚ and ℝ are subsets of ℕ ℤ ℚ and ℝ with >>>>>> 0 or 1 ends. >>>>>> Thus, the standard order is infiniteᵖᵍˢˢ. >>>>>> Thus, by lemma 1, no non.standard order is finiteᵖᵍˢˢ. >>>>>> >>>>>> They do not have any finiteᵖᵍˢˢ order. >>>>>> Whatever non.standard order you propose, >>>>>> you are proposing an infiniteᵖᵍˢˢ order; >>>>>> you are proposing an order with >>>>>> some _subset_ with 0 or 1 ends. >> >>>> Robinson arithmetic has non.standard models >>>> with infinite naturals. >>>> For example, {0}×ℕ ∪ ℚ⁺×ℤ >>>> ⎛ ⟨p,j⟩ <ꟴ ⟨q,k⟩ ⇔ >>>> ⎝ p < q ∨ (p = q ∧ j < k) >>>> >>>> ⎛ Numbers ⟨p,j⟩ and ⟨q,k⟩ with p<q are >>>> ⎝ infinitely.far apart. >>>> ⎛ There are splits between ⟨p,j⟩ and ⟨q,k⟩ >>>> ⎝ with no step from foresplit to hindsplit. >>>> ( ⟨p,j⟩ is not countable.to ⟨q,k⟩ >>>> ( Not all subsets are 2.ended. >> >>> I'm really beginning to warm up to this idea of >>> "finite" and "all orderings are well-orderings" >>> being a thing. >> >> If you're referring to the idea of >> ⎛ for finite, >> ⎝ all orderings are well.ordered both ways >> then I'm pleased to hear >> that you're warming to the idea. >> I wish you much future warming. >> >>> [...] that they're not "immediate" successors, >>> thus it's delineated that they're "deferred" successors. >> >> Standardly, "successor" is "immediate successor". >> >> We have other ways to say "deferred successor". >> For example, "after". >> >> Other than an opportunity to enmurken, >> what does the use of "deferred successor" offer? >> >>> So, ordinals less than a limit ordinal are predecessors, >> >> To review: >> >>>>> So, with "infinite in the middle", it's just >>>>> that the natural order >>>>> 0, infinity - 0, >>>>> 1, infinity - 1, >>>>> ... >>>>> has pretty simply two constants "0", "infinity", >>>>> then successors, >>>>> and it has all the models where infinity equates to >>>>> one of 0's successors, and they're finite, >>>>> and a model where it doesn't, that it's infinite. >> >> This model in which infinity isn't a successor of 0 >> by which you mean infinity doesn't come after 0 >> how would infinity not coming after 0 work, exactly? >> >> > > I mean it's a great definition that finite has that > there exists a normal ordering that's a well-ordering > and that all the orderings of the set are well-orderings. > > That's a great definition of finite and now it stands > for itself in enduring mathematical definition in defense. > > Why is it you think that Stackel's definition of finite > and "not Dedekind's definition of countably infinite" > don't agree? > > The entire idea here that there's a particular _regularity_ > due dispersion and modularity only courtesy division down > from a fixed-point, that "Peano's axioms" don't give integers, > they only give increments, i.e. not necessarily constant increments, > that there's more than one _regularity_, REQUIRED, is another > little fact of mathematics missing from your neat little hedgerow. > > ...., REQUIRED, ....