{"title":"ARTIN–SCHREIER EXTENSIONS AND COMBINATORIAL COMPLEXITY IN HENSELIAN VALUED FIELDS","authors":"BLAISE BOISSONNEAU","doi":"10.1017/jsl.2024.34","DOIUrl":"https://doi.org/10.1017/jsl.2024.34","url":null,"abstract":"<p>We give explicit formulas witnessing IP, IP<span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240911114232841-0471:S0022481224000343:S0022481224000343_inline1.png\"><span data-mathjax-type=\"texmath\"><span>$_{!n}$</span></span></img></span></span>, or TP2 in fields with Artin–Schreier extensions. We use them to control <span>p</span>-extensions of mixed characteristic henselian valued fields, allowing us most notably to generalize to the NIP<span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240911114232841-0471:S0022481224000343:S0022481224000343_inline2.png\"><span data-mathjax-type=\"texmath\"><span>$_{!n}$</span></span></img></span></span> context one way of Anscombe–Jahnke’s classification of NIP henselian valued fields. As a corollary, we obtain that NIP<span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240911114232841-0471:S0022481224000343:S0022481224000343_inline3.png\"><span data-mathjax-type=\"texmath\"><span>$_{!n}$</span></span></img></span></span> henselian valued fields with NIP residue field are NIP. We also discuss tameness results for NTP2 henselian valued fields.</p>","PeriodicalId":501300,"journal":{"name":"The Journal of Symbolic Logic","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142183808","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"BUILDING MODELS IN SMALL CARDINALS IN LOCAL ABSTRACT ELEMENTARY CLASSES","authors":"MARCOS MAZARI-ARMIDA, WENTAO YANG","doi":"10.1017/jsl.2024.32","DOIUrl":"https://doi.org/10.1017/jsl.2024.32","url":null,"abstract":"<p>There are many results in the literature where superstablity-like independence notions, without any categoricity assumptions, have been used to show the existence of larger models. In this paper we show that <span>stability</span> is enough to construct larger models for small cardinals assuming a mild locality condition for Galois types.<span>Theorem 0.1.</span><p>Suppose <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240904081418552-0865:S002248122400032X:S002248122400032X_inline1.png\"><span data-mathjax-type=\"texmath\"><span>$lambda <2^{aleph _0}$</span></span></img></span></span>. Let <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240904081418552-0865:S002248122400032X:S002248122400032X_inline2.png\"><span data-mathjax-type=\"texmath\"><span>${mathbf {K}}$</span></span></img></span></span> be an abstract elementary class with <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240904081418552-0865:S002248122400032X:S002248122400032X_inline3.png\"><span data-mathjax-type=\"texmath\"><span>$lambda geq {operatorname {LS}}({mathbf {K}})$</span></span></img></span></span>. Assume <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240904081418552-0865:S002248122400032X:S002248122400032X_inline4.png\"><span data-mathjax-type=\"texmath\"><span>${mathbf {K}}$</span></span></img></span></span> has amalgamation in <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240904081418552-0865:S002248122400032X:S002248122400032X_inline5.png\"><span data-mathjax-type=\"texmath\"><span>$lambda $</span></span></img></span></span>, no maximal model in <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240904081418552-0865:S002248122400032X:S002248122400032X_inline6.png\"><span data-mathjax-type=\"texmath\"><span>$lambda $</span></span></img></span></span>, and is stable in <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240904081418552-0865:S002248122400032X:S002248122400032X_inline7.png\"><span data-mathjax-type=\"texmath\"><span>$lambda $</span></span></img></span></span>. If <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240904081418552-0865:S002248122400032X:S002248122400032X_inline8.png\"><span data-mathjax-type=\"texmath\"><span>${mathbf {K}}$</span></span></img></span></span> is <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id","PeriodicalId":501300,"journal":{"name":"The Journal of Symbolic Logic","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142183807","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"ONE-DIMENSIONAL SUBGROUPS AND CONNECTED COMPONENTS IN NON-ABELIAN p-ADIC DEFINABLE GROUPS","authors":"WILLIAM JOHNSON, NINGYUAN YAO","doi":"10.1017/jsl.2024.31","DOIUrl":"https://doi.org/10.1017/jsl.2024.31","url":null,"abstract":"<p>We generalize two of our previous results on abelian definable groups in <span>p</span>-adically closed fields [12, 13] to the non-abelian case. First, we show that if <span>G</span> is a definable group that is not definably compact, then <span>G</span> has a one-dimensional definable subgroup which is not definably compact. This is a <span>p</span>-adic analogue of the Peterzil–Steinhorn theorem for o-minimal theories [16]. Second, we show that if <span>G</span> is a group definable over the standard model <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240513074612283-0489:S0022481224000318:S0022481224000318_inline1.png\"><span data-mathjax-type=\"texmath\"><span>$mathbb {Q}_p$</span></span></img></span></span>, then <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240513074612283-0489:S0022481224000318:S0022481224000318_inline2.png\"><span data-mathjax-type=\"texmath\"><span>$G^0 = G^{00}$</span></span></img></span></span>. As an application, definably amenable groups over <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240513074612283-0489:S0022481224000318:S0022481224000318_inline3.png\"><span data-mathjax-type=\"texmath\"><span>$mathbb {Q}_p$</span></span></img></span></span> are open subgroups of algebraic groups, up to finite factors. We also prove that <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240513074612283-0489:S0022481224000318:S0022481224000318_inline4.png\"><span data-mathjax-type=\"texmath\"><span>$G^0 = G^{00}$</span></span></img></span></span> when <span>G</span> is a definable subgroup of a linear algebraic group, over any model.</p>","PeriodicalId":501300,"journal":{"name":"The Journal of Symbolic Logic","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140927122","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Generic Expansions of Geometric Theories","authors":"S. Jalili, M. Pourmahdian, N. R. Tavana","doi":"10.1017/jsl.2024.30","DOIUrl":"https://doi.org/10.1017/jsl.2024.30","url":null,"abstract":"","PeriodicalId":501300,"journal":{"name":"The Journal of Symbolic Logic","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140686353","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"THE DEFINABILITY OF THE EXTENDER SEQUENCE FROM IN","authors":"Farmer Schlutzenberg","doi":"10.1017/jsl.2024.27","DOIUrl":"https://doi.org/10.1017/jsl.2024.27","url":null,"abstract":"","PeriodicalId":501300,"journal":{"name":"The Journal of Symbolic Logic","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140700208","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Discontinuous Homomorphisms of with","authors":"Bob A. Dumas","doi":"10.1017/jsl.2024.28","DOIUrl":"https://doi.org/10.1017/jsl.2024.28","url":null,"abstract":"","PeriodicalId":501300,"journal":{"name":"The Journal of Symbolic Logic","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140699506","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"MORE ON GALOIS COHOMOLOGY, DEFINABILITY, AND DIFFERENTIAL ALGEBRAIC GROUPS","authors":"OMAR LEÓN SÁNCHEZ, DAVID MERETZKY, ANAND PILLAY","doi":"10.1017/jsl.2024.25","DOIUrl":"https://doi.org/10.1017/jsl.2024.25","url":null,"abstract":"<p>As a continuation of the work of the third author in [5], we make further observations on the features of Galois cohomology in the general model theoretic context. We make explicit the connection between forms of definable groups and first cohomology sets with coefficients in a suitable automorphism group. We then use a method of twisting cohomology (inspired by Serre’s algebraic twisting) to describe arbitrary fibres in cohomology sequences—yielding a useful “finiteness” result on cohomology sets.</p><p>Applied to the special case of differential fields and Kolchin’s constrained cohomology, we complete results from [3] by proving that the first constrained cohomology set of a differential algebraic group over a bounded, differentially large, field is countable.</p>","PeriodicalId":501300,"journal":{"name":"The Journal of Symbolic Logic","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140802408","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A SINGLETON OF MINIMAL ARITHMETIC DEGREE","authors":"Peter M. Gerdes","doi":"10.1017/jsl.2024.23","DOIUrl":"https://doi.org/10.1017/jsl.2024.23","url":null,"abstract":"","PeriodicalId":501300,"journal":{"name":"The Journal of Symbolic Logic","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140728911","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"NONDEFINABILITY RESULTS FOR ELLIPTIC AND MODULAR FUNCTIONS","authors":"RAYMOND MCCULLOCH","doi":"10.1017/jsl.2024.22","DOIUrl":"https://doi.org/10.1017/jsl.2024.22","url":null,"abstract":"<p>Let <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240904075918471-0566:S0022481224000227:S0022481224000227_inline1.png\"><span data-mathjax-type=\"texmath\"><span>$Omega $</span></span></img></span></span> be a complex lattice which does not have complex multiplication and <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240904075918471-0566:S0022481224000227:S0022481224000227_inline2.png\"><span data-mathjax-type=\"texmath\"><span>$wp =wp _Omega $</span></span></img></span></span> the Weierstrass <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240904075918471-0566:S0022481224000227:S0022481224000227_inline3.png\"><span data-mathjax-type=\"texmath\"><span>$wp $</span></span></img></span></span>-function associated with it. Let <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240904075918471-0566:S0022481224000227:S0022481224000227_inline4.png\"><span data-mathjax-type=\"texmath\"><span>$Dsubseteq mathbb {C}$</span></span></img></span></span> be a disc and <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240904075918471-0566:S0022481224000227:S0022481224000227_inline5.png\"><span data-mathjax-type=\"texmath\"><span>$Isubseteq mathbb {R}$</span></span></img></span></span> be a bounded closed interval such that <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240904075918471-0566:S0022481224000227:S0022481224000227_inline6.png\"><span data-mathjax-type=\"texmath\"><span>$Icap Omega =varnothing $</span></span></img></span></span>. Let <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240904075918471-0566:S0022481224000227:S0022481224000227_inline7.png\"><span data-mathjax-type=\"texmath\"><span>$f:Drightarrow mathbb {C}$</span></span></img></span></span> be a function definable in <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240904075918471-0566:S0022481224000227:S0022481224000227_inline8.png\"><span data-mathjax-type=\"texmath\"><span>$(overline {mathbb {R}},wp |_I)$</span></span></img></span></span>. We show that if <span>f</span> is holomorphic on <span>D</span> then <span>f</span> is definable in <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240904075918471-0566:S0022481224000227:S0022481224000227_inline9.png\"><span data-mathjax-type=\"texmath\"><span>$overline {mathbb {R}}$</span></span></img></span","PeriodicalId":501300,"journal":{"name":"The Journal of Symbolic Logic","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142223932","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}