Mathematical Logic Quarterly最新文献

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Logics of upsets of De Morgan lattices 德摩根格的逆逻辑
IF 0.3 4区 数学
Mathematical Logic Quarterly Pub Date : 2023-07-31 DOI: 10.1002/malq.202100076
Adam Přenosil
{"title":"Logics of upsets of De Morgan lattices","authors":"Adam Přenosil","doi":"10.1002/malq.202100076","DOIUrl":"10.1002/malq.202100076","url":null,"abstract":"<p>We study logics determined by matrices consisting of a De Morgan lattice with an upward closed set of designated values, such as the logic of non-falsity preservation in a given finite Boolean algebra and Shramko's logic of non-falsity preservation in the four-element subdirectly irreducible De Morgan lattice. The key tool in the study of these logics is the lattice-theoretic notion of an <i>n</i>-filter. We study the logics of all (complete, consistent, and classical) <i>n</i>-filters on De Morgan lattices, which are non-adjunctive generalizations of the four-valued logic of Belnap and Dunn (of the three-valued logics of Priest and Kleene, and of classical logic). We then show how to find a finite Hilbert-style axiomatization of any logic determined by a finite family of prime upsets of finite De Morgan lattices and a finite Gentzen-style axiomatization of any logic determined by a finite family of filters on finite De Morgan lattices. As an application, we axiomatize Shramko's logic of anything but falsehood.</p>","PeriodicalId":49864,"journal":{"name":"Mathematical Logic Quarterly","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2023-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86044937","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Spherically complete models of Hensel minimal valued fields Hensel极小值域的球完全模型
IF 0.3 4区 数学
Mathematical Logic Quarterly Pub Date : 2023-07-28 DOI: 10.1002/malq.202100055
David B. Bradley-Williams, Immanuel Halupczok
{"title":"Spherically complete models of Hensel minimal valued fields","authors":"David B. Bradley-Williams,&nbsp;Immanuel Halupczok","doi":"10.1002/malq.202100055","DOIUrl":"https://doi.org/10.1002/malq.202100055","url":null,"abstract":"<p>We prove that Hensel minimal expansions of finitely ramified Henselian valued fields admit spherically complete immediate elementary extensions. More precisely, the version of Hensel minimality we use is 0-h<sup>mix</sup>-minimality (which, in equi-characteristic 0, amounts to 0-h-minimality).</p>","PeriodicalId":49864,"journal":{"name":"Mathematical Logic Quarterly","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2023-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/malq.202100055","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50124173","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Coding of real-valued continuous functions under WKL $mathsf {WKL}$ WKL$mathsf{WKL}下实值连续函数的编码$
IF 0.3 4区 数学
Mathematical Logic Quarterly Pub Date : 2023-07-24 DOI: 10.1002/malq.202200031
Tatsuji Kawai
{"title":"Coding of real-valued continuous functions under \u0000 \u0000 WKL\u0000 $mathsf {WKL}$","authors":"Tatsuji Kawai","doi":"10.1002/malq.202200031","DOIUrl":"https://doi.org/10.1002/malq.202200031","url":null,"abstract":"<p>In the context of constructive reverse mathematics, we show that weak Kőnig's lemma (<math>\u0000 <semantics>\u0000 <mi>WKL</mi>\u0000 <annotation>$mathsf {WKL}$</annotation>\u0000 </semantics></math>) implies that every pointwise continuous function <math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>f</mi>\u0000 <mo>:</mo>\u0000 <mo>[</mo>\u0000 <mn>0</mn>\u0000 <mo>,</mo>\u0000 <mn>1</mn>\u0000 <mo>]</mo>\u0000 <mo>→</mo>\u0000 <mi>R</mi>\u0000 </mrow>\u0000 <annotation>$f : [0,1]rightarrow mathbb {R}$</annotation>\u0000 </semantics></math> is induced by a code in the sense of reverse mathematics. This, combined with the fact that <math>\u0000 <semantics>\u0000 <mi>WKL</mi>\u0000 <annotation>$mathsf {WKL}$</annotation>\u0000 </semantics></math> implies the Fan theorem, shows that <math>\u0000 <semantics>\u0000 <mi>WKL</mi>\u0000 <annotation>$mathsf {WKL}$</annotation>\u0000 </semantics></math> implies the uniform continuity theorem: every pointwise continuous function <math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>f</mi>\u0000 <mo>:</mo>\u0000 <mo>[</mo>\u0000 <mn>0</mn>\u0000 <mo>,</mo>\u0000 <mn>1</mn>\u0000 <mo>]</mo>\u0000 <mo>→</mo>\u0000 <mi>R</mi>\u0000 </mrow>\u0000 <annotation>$f : [0,1]rightarrow mathbb {R}$</annotation>\u0000 </semantics></math> has a modulus of uniform continuity. Our results are obtained in Heyting arithmetic in all finite types with quantifier-free axiom of choice.</p>","PeriodicalId":49864,"journal":{"name":"Mathematical Logic Quarterly","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2023-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50142952","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
On Hausdorff operators in ZF $mathsf {ZF}$ 关于ZF$mathsf{ZF}中的Hausdorff算子$
IF 0.3 4区 数学
Mathematical Logic Quarterly Pub Date : 2023-07-24 DOI: 10.1002/malq.202300004
Kyriakos Keremedis, Eleftherios Tachtsis
{"title":"On Hausdorff operators in \u0000 \u0000 ZF\u0000 $mathsf {ZF}$","authors":"Kyriakos Keremedis,&nbsp;Eleftherios Tachtsis","doi":"10.1002/malq.202300004","DOIUrl":"https://doi.org/10.1002/malq.202300004","url":null,"abstract":"<p>A Hausdorff space <math>\u0000 <semantics>\u0000 <mrow>\u0000 <mo>(</mo>\u0000 <mi>X</mi>\u0000 <mo>,</mo>\u0000 <mi>T</mi>\u0000 <mo>)</mo>\u0000 </mrow>\u0000 <annotation>$(X,mathcal {T})$</annotation>\u0000 </semantics></math> is called effectively Hausdorff if there exists a function <i>F</i>—called a Hausdorff operator—such that, for every <math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>x</mi>\u0000 <mo>,</mo>\u0000 <mi>y</mi>\u0000 <mo>∈</mo>\u0000 <mi>X</mi>\u0000 </mrow>\u0000 <annotation>$x,yin X$</annotation>\u0000 </semantics></math> with <math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>x</mi>\u0000 <mo>≠</mo>\u0000 <mi>y</mi>\u0000 </mrow>\u0000 <annotation>$xne y$</annotation>\u0000 </semantics></math>, <math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>F</mi>\u0000 <mo>(</mo>\u0000 <mi>x</mi>\u0000 <mo>,</mo>\u0000 <mi>y</mi>\u0000 <mo>)</mo>\u0000 <mo>=</mo>\u0000 <mo>(</mo>\u0000 <mi>U</mi>\u0000 <mo>,</mo>\u0000 <mi>V</mi>\u0000 <mo>)</mo>\u0000 </mrow>\u0000 <annotation>$F(x,y)=(U,V)$</annotation>\u0000 </semantics></math>, where <i>U</i> and <i>V</i> are disjoint open neighborhoods of <i>x</i> and <i>y</i>, respectively. Among other results, we establish the following in <math>\u0000 <semantics>\u0000 <mi>ZF</mi>\u0000 <annotation>$mathsf {ZF}$</annotation>\u0000 </semantics></math>, i.e., in Zermelo–Fraenkel set theory without the Axiom of Choice (<math>\u0000 <semantics>\u0000 <mi>AC</mi>\u0000 <annotation>$mathsf {AC}$</annotation>\u0000 </semantics></math>):</p><p>\u0000 </p>","PeriodicalId":49864,"journal":{"name":"Mathematical Logic Quarterly","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2023-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50142953","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Topological duality for orthomodular lattices 正交模格的拓扑对偶
IF 0.3 4区 数学
Mathematical Logic Quarterly Pub Date : 2023-07-24 DOI: 10.1002/malq.202200044
Joseph McDonald, Katalin Bimbó
{"title":"Topological duality for orthomodular lattices","authors":"Joseph McDonald,&nbsp;Katalin Bimbó","doi":"10.1002/malq.202200044","DOIUrl":"https://doi.org/10.1002/malq.202200044","url":null,"abstract":"<p>A class of ordered relational topological spaces is described, which we call <i>orthomodular spaces</i>. Our construction of these spaces involves adding a topology to the class of orthomodular frames introduced by Hartonas, along the lines of Bimbó's topologization of the class of orthoframes employed by Goldblatt in his representation of ortholattices. We then prove that the category of orthomodular lattices and homomorphisms is dually equivalent to the category of orthomodular spaces and certain continuous frame morphisms, which we call <i>continuous weak p-morphisms</i>. It is well-known that orthomodular lattices provide an algebraic semantics for the quantum logic <math>\u0000 <semantics>\u0000 <mi>Q</mi>\u0000 <annotation>$mathcal {Q}$</annotation>\u0000 </semantics></math>. Hence, as an application of our duality, we develop a topological semantics for <math>\u0000 <semantics>\u0000 <mi>Q</mi>\u0000 <annotation>$mathcal {Q}$</annotation>\u0000 </semantics></math> using orthomodular spaces and prove soundness and completeness.</p>","PeriodicalId":49864,"journal":{"name":"Mathematical Logic Quarterly","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2023-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/malq.202200044","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50153949","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Bowtie-free graphs and generic automorphisms 无Bowtie图与一般自同构
IF 0.3 4区 数学
Mathematical Logic Quarterly Pub Date : 2023-07-24 DOI: 10.1002/malq.202200047
Daoud Siniora
{"title":"Bowtie-free graphs and generic automorphisms","authors":"Daoud Siniora","doi":"10.1002/malq.202200047","DOIUrl":"https://doi.org/10.1002/malq.202200047","url":null,"abstract":"<p>We show that the countable universal ω-categorical bowtie-free graph admits generic automorphisms. Moreover, we show that this graph is not finitely homogenisable.</p>","PeriodicalId":49864,"journal":{"name":"Mathematical Logic Quarterly","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2023-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50119031","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Avoiding Medvedev reductions inside a linear order 避免线性秩序中的梅德韦杰夫减少
IF 0.3 4区 数学
Mathematical Logic Quarterly Pub Date : 2023-07-24 DOI: 10.1002/malq.202200059
Noah Schweber
{"title":"Avoiding Medvedev reductions inside a linear order","authors":"Noah Schweber","doi":"10.1002/malq.202200059","DOIUrl":"https://doi.org/10.1002/malq.202200059","url":null,"abstract":"<p>While every endpointed interval <i>I</i> in a linear order <i>J</i> is, considered as a linear order in its own right, trivially Muchnik-reducible to <i>J</i> itself, this fails for Medvedev-reductions. We construct an extreme example of this: a linear order in which no endpointed interval is Medvedev-reducible to any other, even allowing parameters, except when the two intervals have finite difference. We also construct a scattered linear order which has many endpointed intervals Medvedev-incomparable to itself; the only other known construction of such a linear order yields an ordinal of extremely high complexity, whereas this construction produces a low-level-arithmetic example. Additionally, the constructions here are “coarse” in the sense that they lift to other uniform reducibility notions in place of Medvedev reducibility itself.</p>","PeriodicalId":49864,"journal":{"name":"Mathematical Logic Quarterly","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2023-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50153950","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
A categorical equivalence between logical quantale modules and quantum B-modules 逻辑量子模与量子b模之间的范畴等价
IF 0.3 4区 数学
Mathematical Logic Quarterly Pub Date : 2023-07-20 DOI: 10.1002/malq.202200062
Xianglong Ruan, Xiaochuan Liu
{"title":"A categorical equivalence between logical quantale modules and quantum B-modules","authors":"Xianglong Ruan,&nbsp;Xiaochuan Liu","doi":"10.1002/malq.202200062","DOIUrl":"10.1002/malq.202200062","url":null,"abstract":"<p>This paper introduces the notion of logical quantale module. It proves that there is a dual equivalence between the category of logical quantale modules and the category of quantum B-modules, in the way that every quantum B-module admits a natural embedding into a logical quantale module, the enveloping quantale module.</p>","PeriodicalId":49864,"journal":{"name":"Mathematical Logic Quarterly","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2023-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84190356","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Topological properties of definable sets in ordered Abelian groups of burden 2 负2的有序阿贝尔群中可定义集的拓扑性质
IF 0.3 4区 数学
Mathematical Logic Quarterly Pub Date : 2023-07-14 DOI: 10.1002/malq.202200052
Alfred Dolich, John Goodrick
{"title":"Topological properties of definable sets in ordered Abelian groups of burden 2","authors":"Alfred Dolich,&nbsp;John Goodrick","doi":"10.1002/malq.202200052","DOIUrl":"https://doi.org/10.1002/malq.202200052","url":null,"abstract":"<p>We obtain some new results on the topology of unary definable sets in expansions of densely ordered Abelian groups of burden 2. In the special case in which the structure has dp-rank 2, we show that the existence of an infinite definable discrete set precludes the definability of a set which is dense and codense in an interval, or of a set which is topologically like the Cantor middle-third set (Theorem 2.9). If it has burden 2 and both an infinite discrete set <i>D</i> and a dense-codense set <i>X</i> are definable, then translates of <i>X</i> must witness the Independence Property (Theorem 2.26). In the last section, an explicit example of an ordered Abelian group of burden 2 is given in which both an infinite discrete set and a dense-codense set are definable.</p>","PeriodicalId":49864,"journal":{"name":"Mathematical Logic Quarterly","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2023-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50132671","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
On the variety of strong subresiduated lattices 关于强次边值格的多样性
IF 0.3 4区 数学
Mathematical Logic Quarterly Pub Date : 2023-07-11 DOI: 10.1002/malq.202200067
Sergio Celani, Hernán J. San Martín
{"title":"On the variety of strong subresiduated lattices","authors":"Sergio Celani,&nbsp;Hernán J. San Martín","doi":"10.1002/malq.202200067","DOIUrl":"https://doi.org/10.1002/malq.202200067","url":null,"abstract":"<p>A subresiduated lattice is a pair <math>\u0000 <semantics>\u0000 <mrow>\u0000 <mo>(</mo>\u0000 <mi>A</mi>\u0000 <mo>,</mo>\u0000 <mi>D</mi>\u0000 <mo>)</mo>\u0000 </mrow>\u0000 <annotation>$(A,D)$</annotation>\u0000 </semantics></math>, where <i>A</i> is a bounded distributive lattice, <i>D</i> is a bounded sublattice of <i>A</i> and for every <math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>a</mi>\u0000 <mo>,</mo>\u0000 <mi>b</mi>\u0000 <mo>∈</mo>\u0000 <mi>A</mi>\u0000 </mrow>\u0000 <annotation>$a,bin A$</annotation>\u0000 </semantics></math> there exists the maximum of the set <math>\u0000 <semantics>\u0000 <mrow>\u0000 <mo>{</mo>\u0000 <mi>d</mi>\u0000 <mo>∈</mo>\u0000 <mi>D</mi>\u0000 <mo>:</mo>\u0000 <mi>a</mi>\u0000 <mo>∧</mo>\u0000 <mi>d</mi>\u0000 <mo>≤</mo>\u0000 <mi>b</mi>\u0000 <mo>}</mo>\u0000 </mrow>\u0000 <annotation>$lbrace din D:awedge dle brbrace$</annotation>\u0000 </semantics></math>, which is denoted by <math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>a</mi>\u0000 <mo>→</mo>\u0000 <mi>b</mi>\u0000 </mrow>\u0000 <annotation>$arightarrow b$</annotation>\u0000 </semantics></math>. This pair can be regarded as an algebra <math>\u0000 <semantics>\u0000 <mrow>\u0000 <mo>(</mo>\u0000 <mi>A</mi>\u0000 <mo>,</mo>\u0000 <mo>∧</mo>\u0000 <mo>,</mo>\u0000 <mo>∨</mo>\u0000 <mo>,</mo>\u0000 <mo>→</mo>\u0000 <mo>,</mo>\u0000 <mn>0</mn>\u0000 <mo>,</mo>\u0000 <mn>1</mn>\u0000 <mo>)</mo>\u0000 </mrow>\u0000 <annotation>$(A,wedge ,vee ,rightarrow ,0,1)$</annotation>\u0000 </semantics></math> of type (2, 2, 2, 0, 0), where <math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>D</mi>\u0000 <mo>=</mo>\u0000 <mo>{</mo>\u0000 <mi>a</mi>\u0000 <mo>∈</mo>\u0000 <mi>A</mi>\u0000 <mo>:</mo>\u0000 <mn>1</mn>\u0000 <mo>→</mo>\u0000 <mi>a</mi>\u0000 <mo>=</mo>\u0000 <mi>a</mi>\u0000 <mo>}</mo>\u0000 </mrow>\u0000 <annotation>$D=lbrace ain A: 1rightarrow a =arbrace$</annotation>\u0000 </semantics></math>. The class of subresiduated lattices is a variety which properly contains the variety of Heyting algebras. In this paper we study the subvariety of subresiduated lattices, denoted by <math>\u0000 <semantics>\u0000 <msup>\u0000 ","PeriodicalId":49864,"journal":{"name":"Mathematical Logic Quarterly","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2023-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50128774","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
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