{"title":"坚不可摧和米切尔排序的直线性","authors":"Arthur W. Apter","doi":"10.1007/s00153-024-00908-7","DOIUrl":null,"url":null,"abstract":"<div><p>Suppose that <span>\\(\\kappa \\)</span> is indestructibly supercompact and there is a measurable cardinal <span>\\(\\lambda > \\kappa \\)</span>. It then follows that <span>\\(A_0 = \\{\\delta < \\kappa \\mid \\delta \\)</span> is a measurable cardinal and the Mitchell ordering of normal measures over <span>\\(\\delta \\)</span> is nonlinear<span>\\(\\}\\)</span> is unbounded in <span>\\(\\kappa \\)</span>. If the Mitchell ordering of normal measures over <span>\\(\\lambda \\)</span> is also linear, then by reflection (and without any use of indestructibility), <span>\\(A_1= \\{\\delta < \\kappa \\mid \\delta \\)</span> is a measurable cardinal and the Mitchell ordering of normal measures over <span>\\(\\delta \\)</span> is linear<span>\\(\\}\\)</span> is unbounded in <span>\\(\\kappa \\)</span> as well. The large cardinal hypothesis on <span>\\(\\lambda \\)</span> is necessary. We demonstrate this by constructing via forcing two models in which <span>\\(\\kappa \\)</span> is supercompact and <span>\\(\\kappa \\)</span> exhibits an indestructibility property slightly weaker than full indestructibility but sufficient to infer that <span>\\(A_0\\)</span> is unbounded in <span>\\(\\kappa \\)</span> if <span>\\(\\lambda > \\kappa \\)</span> is measurable. In one of these models, for every measurable cardinal <span>\\(\\delta \\)</span>, the Mitchell ordering of normal measures over <span>\\(\\delta \\)</span> is linear. In the other of these models, for every measurable cardinal <span>\\(\\delta \\)</span>, the Mitchell ordering of normal measures over <span>\\(\\delta \\)</span> is nonlinear.</p></div>","PeriodicalId":48853,"journal":{"name":"Archive for Mathematical Logic","volume":"63 3-4","pages":""},"PeriodicalIF":0.3000,"publicationDate":"2024-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Indestructibility and the linearity of the Mitchell ordering\",\"authors\":\"Arthur W. Apter\",\"doi\":\"10.1007/s00153-024-00908-7\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>Suppose that <span>\\\\(\\\\kappa \\\\)</span> is indestructibly supercompact and there is a measurable cardinal <span>\\\\(\\\\lambda > \\\\kappa \\\\)</span>. It then follows that <span>\\\\(A_0 = \\\\{\\\\delta < \\\\kappa \\\\mid \\\\delta \\\\)</span> is a measurable cardinal and the Mitchell ordering of normal measures over <span>\\\\(\\\\delta \\\\)</span> is nonlinear<span>\\\\(\\\\}\\\\)</span> is unbounded in <span>\\\\(\\\\kappa \\\\)</span>. If the Mitchell ordering of normal measures over <span>\\\\(\\\\lambda \\\\)</span> is also linear, then by reflection (and without any use of indestructibility), <span>\\\\(A_1= \\\\{\\\\delta < \\\\kappa \\\\mid \\\\delta \\\\)</span> is a measurable cardinal and the Mitchell ordering of normal measures over <span>\\\\(\\\\delta \\\\)</span> is linear<span>\\\\(\\\\}\\\\)</span> is unbounded in <span>\\\\(\\\\kappa \\\\)</span> as well. The large cardinal hypothesis on <span>\\\\(\\\\lambda \\\\)</span> is necessary. We demonstrate this by constructing via forcing two models in which <span>\\\\(\\\\kappa \\\\)</span> is supercompact and <span>\\\\(\\\\kappa \\\\)</span> exhibits an indestructibility property slightly weaker than full indestructibility but sufficient to infer that <span>\\\\(A_0\\\\)</span> is unbounded in <span>\\\\(\\\\kappa \\\\)</span> if <span>\\\\(\\\\lambda > \\\\kappa \\\\)</span> is measurable. In one of these models, for every measurable cardinal <span>\\\\(\\\\delta \\\\)</span>, the Mitchell ordering of normal measures over <span>\\\\(\\\\delta \\\\)</span> is linear. In the other of these models, for every measurable cardinal <span>\\\\(\\\\delta \\\\)</span>, the Mitchell ordering of normal measures over <span>\\\\(\\\\delta \\\\)</span> is nonlinear.</p></div>\",\"PeriodicalId\":48853,\"journal\":{\"name\":\"Archive for Mathematical Logic\",\"volume\":\"63 3-4\",\"pages\":\"\"},\"PeriodicalIF\":0.3000,\"publicationDate\":\"2024-02-13\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Archive for Mathematical Logic\",\"FirstCategoryId\":\"100\",\"ListUrlMain\":\"https://link.springer.com/article/10.1007/s00153-024-00908-7\",\"RegionNum\":4,\"RegionCategory\":\"数学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"Arts and Humanities\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Archive for Mathematical Logic","FirstCategoryId":"100","ListUrlMain":"https://link.springer.com/article/10.1007/s00153-024-00908-7","RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"Arts and Humanities","Score":null,"Total":0}
引用次数: 0
摘要
Abstract Suppose that \(\kappa \) is indestructibly supercompact and there is a measurable cardinal \(\lambda > \kappa \) .然后可以得出:\(A_0 = \{\delta < \kappa \mid \delta \)是一个可测的红心,并且在\(\delta \)上的正态度量的米切尔排序是非线性的 \(\}\)在\(\kappa \)中是无界的。如果在\(\lambda \)上的正则量的米切尔排序也是线性的,那么通过反射(并且不使用任何不可破坏性),\(A_1= \{delta < \kappa \mid \delta \)是一个可测的红心,并且在\(\delta \)上的正则量的米切尔排序是线性的 \(\}\)在\(\kappa \)中也是无界的。关于(lambda)的大心假设是必要的。我们通过强制构造两个模型来证明这一点,在这两个模型中,\(\kappa \)是超紧凑的,并且\(\kappa \)表现出比完全不可破坏性稍弱的不可破坏性,但足以推断出如果\(\lambda > \kappa \)是可测量的,那么\(A_0\)在\(\kappa \)中是无界的。在其中一个模型中,对于每一个可测的红心数((\delta \)),在(\delta \)上的正态度量的米切尔排序是线性的。在其中的另一个模型中,对于每一个可测的红心数(\Δ\),在(\Δ\)上的正态度量的米切尔排序是非线性的。
Indestructibility and the linearity of the Mitchell ordering
Suppose that \(\kappa \) is indestructibly supercompact and there is a measurable cardinal \(\lambda > \kappa \). It then follows that \(A_0 = \{\delta < \kappa \mid \delta \) is a measurable cardinal and the Mitchell ordering of normal measures over \(\delta \) is nonlinear\(\}\) is unbounded in \(\kappa \). If the Mitchell ordering of normal measures over \(\lambda \) is also linear, then by reflection (and without any use of indestructibility), \(A_1= \{\delta < \kappa \mid \delta \) is a measurable cardinal and the Mitchell ordering of normal measures over \(\delta \) is linear\(\}\) is unbounded in \(\kappa \) as well. The large cardinal hypothesis on \(\lambda \) is necessary. We demonstrate this by constructing via forcing two models in which \(\kappa \) is supercompact and \(\kappa \) exhibits an indestructibility property slightly weaker than full indestructibility but sufficient to infer that \(A_0\) is unbounded in \(\kappa \) if \(\lambda > \kappa \) is measurable. In one of these models, for every measurable cardinal \(\delta \), the Mitchell ordering of normal measures over \(\delta \) is linear. In the other of these models, for every measurable cardinal \(\delta \), the Mitchell ordering of normal measures over \(\delta \) is nonlinear.
期刊介绍:
The journal publishes research papers and occasionally surveys or expositions on mathematical logic. Contributions are also welcomed from other related areas, such as theoretical computer science or philosophy, as long as the methods of mathematical logic play a significant role. The journal therefore addresses logicians and mathematicians, computer scientists, and philosophers who are interested in the applications of mathematical logic in their own field, as well as its interactions with other areas of research.