{"title":"Partial Dedekind zeta values for ideal classes of the real quadratic field ({mathbb {Q}})((sqrt{9m^{2}+2m}))","authors":"Ahmad Issa, Boushra Darrag","doi":"10.1007/s00013-024-02037-2","DOIUrl":"10.1007/s00013-024-02037-2","url":null,"abstract":"<div><p>In this paper, we obtain some of the partial Dedekind zeta values for ideal classes of the real quadratic field <span>({mathbb {Q}})</span>(<span>(sqrt{D}))</span>, where <span>(D = 9m^{2}+2m)</span> is a square-free positive integer and <span>(m equiv 2)</span> (mod 3) is an odd positive integer.</p></div>","PeriodicalId":8346,"journal":{"name":"Archiv der Mathematik","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2024-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141935935","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":"Combinatorial constructions of repairable threshold schemes","authors":"Jinghui Zhao, Xiuling Shan, Zihong Tian, Guohui Hao","doi":"10.1007/s00013-024-02034-5","DOIUrl":"10.1007/s00013-024-02034-5","url":null,"abstract":"<div><p>A repairable threshold scheme is a threshold scheme in which a player can securely reconstruct a lost share with the help from a subset of players. In 2018, Stinson and Wei proposed distribution designs to construct repairable threshold schemes. In this paper, we use packing quadruples as distribution designs to distribute subshares of a ramp scheme. The resulting repairable threshold scheme has lower computational complexity and repairing degree.</p></div>","PeriodicalId":8346,"journal":{"name":"Archiv der Mathematik","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2024-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141935934","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":"Global hypersurfaces of section for geodesic flows on convex hypersurfaces","authors":"Sunghae Cho, Dongho Lee","doi":"10.1007/s00013-024-02018-5","DOIUrl":"10.1007/s00013-024-02018-5","url":null,"abstract":"<div><p>We construct a global hypersurface of section for the geodesic flow of a convex hypersurface in Euclidean space admitting an isometric involution. This generalizes the Birkhoff annulus to higher dimensions.</p></div>","PeriodicalId":8346,"journal":{"name":"Archiv der Mathematik","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141867933","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 motivic proof of the finiteness of the relative de Rham cohomology","authors":"Alberto Vezzani","doi":"10.1007/s00013-024-02024-7","DOIUrl":"10.1007/s00013-024-02024-7","url":null,"abstract":"<div><p>We give a quick proof of the fact that the relative de Rham cohomology groups <span>(H^i_{{{,textrm{dR},}}}(X/S))</span> of a smooth and proper map <i>X</i>/<i>S</i> between schemes over <span>({mathbb {Q}})</span> are vector bundles on the base, replacing Hodge-theoretic and transcendental methods with <span>({mathbb {A}}^1)</span>-homotopy theory.</p></div>","PeriodicalId":8346,"journal":{"name":"Archiv der Mathematik","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141867934","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 new lower bound for the (textrm{L}^2)-norm of the Caputo fractional derivative","authors":"Marc Jornet","doi":"10.1007/s00013-024-02033-6","DOIUrl":"10.1007/s00013-024-02033-6","url":null,"abstract":"<div><p>We prove a novel, tight lower bound for the norm in <span>(textrm{L}^2[0,T])</span> of the Caputo fractional derivative. It is based on continuous linear functionals, Peano kernels, and the Gaussian hypergeometric function.</p></div>","PeriodicalId":8346,"journal":{"name":"Archiv der Mathematik","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2024-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00013-024-02033-6.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141742240","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":"Reduced polygons in the hyperbolic plane","authors":"Marek Lassak","doi":"10.1007/s00013-024-02009-6","DOIUrl":"10.1007/s00013-024-02009-6","url":null,"abstract":"<div><p>For a hyperplane <i>H</i> supporting a convex body <i>C</i> in the hyperbolic space <span>(mathbb {H}^d)</span>, we define the width of <i>C</i> determined by <i>H</i> as the distance between <i>H</i> and a most distant ultraparallel hyperplane supporting <i>C</i>. The minimum width of <i>C</i> over all supporting <i>H</i> is called the thickness <span>(Delta (C))</span> of <i>C</i>. A convex body <span>(R subset mathbb {H}^{d})</span> is said to be reduced if <span>(Delta (Z) < Delta (R))</span> for every convex body <i>Z</i> properly contained in <i>R</i>. We describe a class of reduced polygons in <span>(mathbb {H}^{2})</span> and present some properties of them. In particular, we estimate their diameters in terms of their thicknesses.</p></div>","PeriodicalId":8346,"journal":{"name":"Archiv der Mathematik","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2024-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00013-024-02009-6.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141742241","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":"Moduli of uniform convexity for convex sets","authors":"Carlo Alberto De Bernardi, Libor Veselý","doi":"10.1007/s00013-024-02031-8","DOIUrl":"10.1007/s00013-024-02031-8","url":null,"abstract":"<div><p>Let <i>C</i> be a proper, closed subset with nonempty interior in a normed space <i>X</i>. We define four variants of modulus of convexity for <i>C</i> and prove that they all coincide. This result, which is classical and well-known for <span>(C=B_X)</span> (the unit ball of <i>X</i>), requires a less easy proof than the particular case of <span>(B_X.)</span> We also show that if the modulus of convexity of <i>C</i> is not identically null, then <i>C</i> is bounded. This extends a result by M.V. Balashov and D. Repovš.</p></div>","PeriodicalId":8346,"journal":{"name":"Archiv der Mathematik","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2024-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00013-024-02031-8.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141742239","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":"Decidability of the Brinkmann problems for endomorphisms of the free group","authors":"André Carvalho, Jordi Delgado","doi":"10.1007/s00013-024-02029-2","DOIUrl":"10.1007/s00013-024-02029-2","url":null,"abstract":"<div><p>Building on the work of Brinkmann and Logan, we show that both the Brinkmann problem and the Brinkmann conjugacy problem are decidable for endomorphisms of the free group <span>(mathbb {F}_{n})</span>.</p></div>","PeriodicalId":8346,"journal":{"name":"Archiv der Mathematik","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2024-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141742243","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 criterion for sequential Cohen-Macaulayness","authors":"Giulio Caviglia, Alessandro De Stefani","doi":"10.1007/s00013-024-02011-y","DOIUrl":"10.1007/s00013-024-02011-y","url":null,"abstract":"<div><p>The purpose of this note is to show that a finitely generated graded module <i>M</i> over <span>(S=k[x_1,ldots ,x_n])</span>, <i>k</i> a field, is sequentially Cohen-Macaulay if and only if its arithmetic degree <span>({text {adeg}}(M))</span> agrees with <span>({text {adeg}}(F/{text {gin}}_textrm{revlex}(U)))</span>, where <i>F</i> is a graded free <i>S</i>-module and <span>(M cong F/U)</span>. This answers positively a conjecture of Lu and Yu from 2016.</p></div>","PeriodicalId":8346,"journal":{"name":"Archiv der Mathematik","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2024-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00013-024-02011-y.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141742244","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 remark on the boundedness of the Hardy–Littlewood maximal operator on Orlicz–Lorentz spaces","authors":"Zhiwei Hao, Lin Wang","doi":"10.1007/s00013-024-02028-3","DOIUrl":"10.1007/s00013-024-02028-3","url":null,"abstract":"<div><p>In this paper, we give an alternative proof of the main result in Hatano et al. (Tokyo J Math 46(1):125–160, 2023) that the Hardy–Littlewood maximal operator is bounded on the Orlicz–Lorentz space <span>(L^{Phi ,q}({mathbb {R}}^n))</span> for a Young function <span>(Phi in nabla _2)</span> and <span>(0<q<1.)</span></p></div>","PeriodicalId":8346,"journal":{"name":"Archiv der Mathematik","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2024-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141742428","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}