{"title":"Alternating multiple mixed values: Regularization, special values, parity, and dimension conjectures","authors":"","doi":"10.1016/j.indag.2024.06.001","DOIUrl":"10.1016/j.indag.2024.06.001","url":null,"abstract":"<div><div>In this paper, we define and study a variant of multiple zeta values (MZVs) of level four, called alternating multiple mixed values or alternating multiple <span><math><mi>M</mi></math></span>-values (AMMVs), forming a <span><math><mrow><mi>Q</mi><mrow><mo>[</mo><mi>i</mi><mo>]</mo></mrow></mrow></math></span>-subspace of the colored MZVs of level four. This variant includes the alternating version of Hoffman’s multiple <span><math><mi>t</mi></math></span>-values, Kaneko–Tsumura’s multiple <span><math><mi>T</mi></math></span>-values, and the multiple <span><math><mi>S</mi></math></span>-values studied by the authors previously as special cases. We exhibit nice properties similar to the ordinary MZVs such as the generalized duality, integral shuffle and series stuffle relations. After setting up the algebraic framework we derive the regularized double shuffle relations of the AMMVs by adopting the machinery from color MZVs of level four. As an important application, we prove a parity result for AMMVs previously conjectured by two of us. We also investigate several alternating multiple <span><math><mi>S</mi></math></span>- and <span><math><mi>T</mi></math></span>-values by establishing some explicit relations of integrals involving arctangent function. At the end, we compute the dimensions of a few interesting subspaces of AMMVs for weight less than 9. Supported by theoretical and numerical evidence aided by numerical and symbolic computation, we formulate a few conjectures concerning the dimensions of the above-mentioned subspaces of AMMVs. These conjectures hint at a few very rich but previously overlooked algebraic and geometric structures associated with these vector spaces.</div></div>","PeriodicalId":56126,"journal":{"name":"Indagationes Mathematicae-New Series","volume":"35 6","pages":"Pages 1212-1248"},"PeriodicalIF":0.5,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141504919","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}
{"title":"Class numbers, Ono invariants and some interesting primes","authors":"","doi":"10.1016/j.indag.2024.06.003","DOIUrl":"10.1016/j.indag.2024.06.003","url":null,"abstract":"<div><div>Our aim is to find all the prime numbers <span><math><mi>p</mi></math></span> such that <span><math><mrow><mi>p</mi><mo>+</mo><msup><mrow><mi>x</mi></mrow><mrow><mn>2</mn></mrow></msup></mrow></math></span> has at most two different prime factors, for all the odd integers <span><math><mi>x</mi></math></span> such that <span><math><mrow><msup><mrow><mi>x</mi></mrow><mrow><mn>2</mn></mrow></msup><mo>≤</mo><mi>p</mi></mrow></math></span>. We solve entirely the cases <span><math><mrow><mi>p</mi><mo>≡</mo><mn>1</mn><mo>,</mo><mn>3</mn><mo>,</mo><mn>5</mn><mspace></mspace><mrow><mo>(</mo><mo>mod</mo><mspace></mspace><mn>8</mn><mo>)</mo></mrow></mrow></math></span>, using the knowledge of the quadratic imaginary number fields with class numbers 4, 1 and 2 respectively. The case <span><math><mrow><mi>p</mi><mo>≡</mo><mn>7</mn><mspace></mspace><mrow><mo>(</mo><mo>mod</mo><mspace></mspace><mn>8</mn><mo>)</mo></mrow></mrow></math></span> is not completely solved. Taking into account a result of Stéphane Louboutin, we prove that there is at most one value <span><math><mrow><mi>p</mi><mo>≡</mo><mn>7</mn><mspace></mspace><mrow><mo>(</mo><mo>mod</mo><mspace></mspace><mn>8</mn><mo>)</mo></mrow></mrow></math></span> besides our list. Assuming a Restricted Riemann Hypothesis, the list is complete. In the last section of the paper we give a short sketch for the general problem: find all odd integers <span><math><mrow><mi>n</mi><mo>></mo><mn>1</mn></mrow></math></span> such that <span><math><mrow><mi>n</mi><mo>+</mo><msup><mrow><mi>x</mi></mrow><mrow><mn>2</mn></mrow></msup></mrow></math></span> has at most two different prime factors, for all the odd integers <span><math><mi>x</mi></math></span> such that <span><math><mrow><msup><mrow><mi>x</mi></mrow><mrow><mn>2</mn></mrow></msup><mo>≤</mo><mi>n</mi></mrow></math></span>.</div></div>","PeriodicalId":56126,"journal":{"name":"Indagationes Mathematicae-New Series","volume":"35 6","pages":"Pages 1249-1258"},"PeriodicalIF":0.5,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141504918","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}
{"title":"Integral expressions for Schur multiple zeta values","authors":"","doi":"10.1016/j.indag.2024.05.010","DOIUrl":"10.1016/j.indag.2024.05.010","url":null,"abstract":"<div><div>Nakasuji, Phuksuwan, and Yamasaki defined the Schur multiple zeta values and gave iterated integral expressions of the Schur multiple zeta values of the ribbon type. This paper generalizes their integral expressions to the ones of more general Schur multiple zeta values having constant entries on the diagonals. Furthermore, we also discuss the duality relations for Schur multiple zeta values obtained from the integral expressions.</div></div>","PeriodicalId":56126,"journal":{"name":"Indagationes Mathematicae-New Series","volume":"35 6","pages":"Pages 1197-1211"},"PeriodicalIF":0.5,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141528966","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}
{"title":"Simple modules for untwisted affine Lie algebras induced from nilpotent loop subalgebras","authors":"","doi":"10.1016/j.indag.2024.05.003","DOIUrl":"10.1016/j.indag.2024.05.003","url":null,"abstract":"<div><div>We construct large families of simple modules for untwisted affine Lie algebras using induction from one-dimensional modules over nilpotent loop subalgebras. We also show that the vector space of the first self-extensions for these module has uncountable dimension and that generic tensor products of these modules are simple.</div></div>","PeriodicalId":56126,"journal":{"name":"Indagationes Mathematicae-New Series","volume":"35 6","pages":"Pages 1138-1148"},"PeriodicalIF":0.5,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141060172","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}
{"title":"Functorial splitting of l-adic cohomology of an extension of group varieties","authors":"","doi":"10.1016/j.indag.2024.05.006","DOIUrl":"10.1016/j.indag.2024.05.006","url":null,"abstract":"<div><div>In this document we consider an exact sequence of group varieties <span><math><mrow><mi>e</mi><mo>→</mo><mi>N</mi><mo>→</mo><mi>G</mi><mo>→</mo><mi>Q</mi><mo>→</mo></mrow></math></span> <span><math><mi>e</mi></math></span> over an algebraically closed field. We show that for <span><math><mrow><mi>l</mi><mo>≠</mo><mi>char</mi><mrow><mo>(</mo><mi>k</mi><mo>)</mo></mrow></mrow></math></span> a prime there exists an isomorphism of graded <span><math><msub><mrow><mi>Q</mi></mrow><mrow><mi>l</mi></mrow></msub></math></span>-algebras <span><math><mrow><msubsup><mrow><mi>H</mi></mrow><mrow><mover><mrow><mi>e</mi></mrow><mrow><mo>́</mo></mrow></mover><mi>t</mi></mrow><mrow><mo>∗</mo></mrow></msubsup><mrow><mo>(</mo><mi>G</mi><mo>,</mo><msub><mrow><mi>Q</mi></mrow><mrow><mi>l</mi></mrow></msub><mo>)</mo></mrow><mo>≅</mo><msubsup><mrow><mi>H</mi></mrow><mrow><mover><mrow><mi>e</mi></mrow><mrow><mo>́</mo></mrow></mover><mi>t</mi></mrow><mrow><mo>∗</mo></mrow></msubsup><mrow><mo>(</mo><mi>N</mi><mo>,</mo><msub><mrow><mi>Q</mi></mrow><mrow><mi>l</mi></mrow></msub><mo>)</mo></mrow><msub><mrow><mo>⊗</mo></mrow><mrow><msub><mrow><mi>Q</mi></mrow><mrow><mi>l</mi></mrow></msub></mrow></msub><msubsup><mrow><mi>H</mi></mrow><mrow><mover><mrow><mi>e</mi></mrow><mrow><mo>́</mo></mrow></mover><mi>t</mi></mrow><mrow><mo>∗</mo></mrow></msubsup><mrow><mo>(</mo><mi>Q</mi><mo>,</mo><msub><mrow><mi>Q</mi></mrow><mrow><mi>l</mi></mrow></msub><mo>)</mo></mrow></mrow></math></span> that is compatible with pullback homomorphisms <span><math><msup><mrow><mi>φ</mi></mrow><mrow><mo>∗</mo></mrow></msup></math></span> of endomorphisms <span><math><mrow><mi>φ</mi><mo>:</mo><mi>G</mi><mo>→</mo><mi>G</mi></mrow></math></span> that stabilize <span><math><mi>N</mi></math></span>.</div></div>","PeriodicalId":56126,"journal":{"name":"Indagationes Mathematicae-New Series","volume":"35 6","pages":"Pages 1185-1196"},"PeriodicalIF":0.5,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141504921","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}
{"title":"A characterization of differential operators in the ring of complex polynomials","authors":"Włodzimierz Fechner , Eszter Gselmann","doi":"10.1016/j.indag.2024.07.011","DOIUrl":"10.1016/j.indag.2024.07.011","url":null,"abstract":"<div><div>The paper aims to provide a full characterization of all operators <span><math><mrow><mi>T</mi><mo>:</mo><mi>P</mi><mrow><mo>(</mo><mi>ℂ</mi><mo>)</mo></mrow><mo>→</mo><mi>P</mi><mrow><mo>(</mo><mi>ℂ</mi><mo>)</mo></mrow></mrow></math></span> acting on the space of all complex polynomials that satisfy the Leibniz rule <span><span><span><math><mrow><mi>T</mi><mrow><mo>(</mo><mi>f</mi><mi>⋅</mi><mi>g</mi><mo>)</mo></mrow><mo>=</mo><mi>T</mi><mrow><mo>(</mo><mi>f</mi><mo>)</mo></mrow><mi>⋅</mi><mi>g</mi><mo>+</mo><mi>f</mi><mi>⋅</mi><mi>T</mi><mrow><mo>(</mo><mi>g</mi><mo>)</mo></mrow></mrow></math></span></span></span>for all <span><math><mrow><mi>f</mi><mo>,</mo><mi>g</mi><mo>∈</mo><mi>P</mi><mrow><mo>(</mo><mi>ℂ</mi><mo>)</mo></mrow></mrow></math></span>. We do not assume the linearity of <span><math><mi>T</mi></math></span>. As we will see, contrary to the well-known theorems for function spaces there are many other solutions here, not only differential operators. From our main result, we also derive two corollaries, showing that in some special cases operators that satisfy the Leibniz rule have some particular form.</div></div>","PeriodicalId":56126,"journal":{"name":"Indagationes Mathematicae-New Series","volume":"35 6","pages":"Pages 1294-1305"},"PeriodicalIF":0.5,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142571884","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}
{"title":"Finite odometer factors of rank one group actions","authors":"","doi":"10.1016/j.indag.2024.04.012","DOIUrl":"10.1016/j.indag.2024.04.012","url":null,"abstract":"<div><div><span>In this paper, we give explicit conditions characterizing the Følner rank one group actions that factor onto a finite odometer; those that factor onto an arbitrary, but specified odometer, and those that factor onto an unspecified odometer. We also give explicit conditions describing the Følner rank one actions that are conjugate to a specific odometer, and those that are conjugate to some odometer. These conditions are based on cutting and stacking procedures used to generate the action, and generalize results given by Foreman, Gao, Hill, Silva and Weiss for rank one </span><span><math><mi>Z</mi></math></span>-actions.</div></div>","PeriodicalId":56126,"journal":{"name":"Indagationes Mathematicae-New Series","volume":"35 6","pages":"Pages 1105-1137"},"PeriodicalIF":0.5,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141032515","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}
{"title":"A note on the inverse problem for finite differential Galois groups","authors":"","doi":"10.1016/j.indag.2024.06.005","DOIUrl":"10.1016/j.indag.2024.06.005","url":null,"abstract":"<div><div>In this paper we revisit the following inverse problem: given a curve invariant under an irreducible finite linear algebraic group, can we construct an ordinary linear differential equation whose Schwarz map parametrizes it? We present an algorithmic solution to this problem under the assumption that we are given the function field of the quotient curve. The result provides a generalization and an efficient implementation of the solution to the inverse problem exposed by van der Put et al. (2020). As an application, we show that there is no hypergeometric equation with projective differential Galois group isomorphic to <span><math><msub><mrow><mi>H</mi></mrow><mrow><mn>72</mn></mrow></msub></math></span>, thus completing Beukers and Heckman’s answer (Beukers and Heckman, 1989) to the question of which irreducible finite subgroup of <span><math><mrow><mi>P</mi><mi>S</mi><msub><mrow><mi>L</mi></mrow><mrow><mn>3</mn></mrow></msub><mrow><mo>(</mo><mi>ℂ</mi><mo>)</mo></mrow></mrow></math></span> are the projective monodromy of a hypergeometric equation.</div></div>","PeriodicalId":56126,"journal":{"name":"Indagationes Mathematicae-New Series","volume":"35 6","pages":"Pages 1259-1269"},"PeriodicalIF":0.5,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141569879","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}
{"title":"An analogue of a conjecture of Rasmussen and Tamagawa for abelian varieties over function fields","authors":"Mentzelos Melistas","doi":"10.1016/j.indag.2024.06.007","DOIUrl":"10.1016/j.indag.2024.06.007","url":null,"abstract":"<div><div>Let <span><math><mi>L</mi></math></span> be a number field and let <span><math><mi>ℓ</mi></math></span> be a prime number. Rasmussen and Tamagawa conjectured, in a precise sense, that abelian varieties whose field of definition of the <span><math><mi>ℓ</mi></math></span>-power torsion is both a pro-<span><math><mi>ℓ</mi></math></span> extension of <span><math><mrow><mi>L</mi><mrow><mo>(</mo><msub><mrow><mi>μ</mi></mrow><mrow><mi>ℓ</mi></mrow></msub><mo>)</mo></mrow></mrow></math></span> and unramified away from <span><math><mi>ℓ</mi></math></span> are quite rare. In this paper, we formulate an analogue of the Rasmussen–Tamagawa conjecture for non-isotrivial abelian varieties defined over function fields. We provide a proof of our analogue in the case of elliptic curves. In higher dimensions, when the base field is a subfield of the complex numbers, we show that our conjecture is a consequence of the uniform geometric torsion conjecture. Finally, using a theorem of Bakker and Tsimerman we also prove our conjecture unconditionally for abelian varieties with real multiplication.</div></div>","PeriodicalId":56126,"journal":{"name":"Indagationes Mathematicae-New Series","volume":"35 6","pages":"Pages 1270-1281"},"PeriodicalIF":0.5,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141690718","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}
{"title":"The Generalized Riemann Hypothesis from zeros of a single L-function","authors":"William Banks","doi":"10.1016/j.indag.2024.07.009","DOIUrl":"10.1016/j.indag.2024.07.009","url":null,"abstract":"<div><div>For each primitive Dirichlet character <span><math><mi>χ</mi></math></span>, a hypothesis <span><math><mrow><msup><mrow><mi>GRH</mi></mrow><mrow><mi>†</mi></mrow></msup><mrow><mo>[</mo><mi>χ</mi><mo>]</mo></mrow></mrow></math></span> is formulated in terms of zeros of the associated <span><math><mi>L</mi></math></span>-function <span><math><mrow><mi>L</mi><mrow><mo>(</mo><mi>s</mi><mo>,</mo><mi>χ</mi><mo>)</mo></mrow></mrow></math></span>. It is shown that for any such character, <span><math><mrow><msup><mrow><mi>GRH</mi></mrow><mrow><mi>†</mi></mrow></msup><mrow><mo>[</mo><mi>χ</mi><mo>]</mo></mrow></mrow></math></span> is equivalent to the Generalized Riemann Hypothesis.</div></div>","PeriodicalId":56126,"journal":{"name":"Indagationes Mathematicae-New Series","volume":"35 6","pages":"Pages 1282-1293"},"PeriodicalIF":0.5,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141845529","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}