{"title":"Noncommutative Algebra and Representation Theory: Symmetry, Structure & Invariants","authors":"S. A. Lopes","doi":"10.46298/cm.11678","DOIUrl":"https://doi.org/10.46298/cm.11678","url":null,"abstract":"This is an abridged version of our Habilitation thesis. In these notes, we aim to summarize our research interests and achievements as well as motivate what drives our work: symmetry, structure and invariants. The paradigmatic example which permeates and often inspires our research is the Weyl algebra $mathbb{A}_{1}$.","PeriodicalId":37836,"journal":{"name":"Communications in Mathematics","volume":"26 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139353090","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 recursive formula for the product of element orders of finite abelian groups","authors":"Subhrajyoti Saha","doi":"10.46298/cm.10996","DOIUrl":"https://doi.org/10.46298/cm.10996","url":null,"abstract":"Let G be a finite group and let ψ(G) denote the sum of element orders of G; later this concept has been used to define R(G) which is the product of the element orders of G. Motivated by the recursive formula for ψ(G), we consider a finite abelian group G and obtain a similar formula for R(G).","PeriodicalId":37836,"journal":{"name":"Communications in Mathematics","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44276178","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":"Matrix formulas for multiplicities in the spin module","authors":"Lucas Fresse, S. Mehdi","doi":"10.46298/cm.11156","DOIUrl":"https://doi.org/10.46298/cm.11156","url":null,"abstract":"We obtain inductive and enumerative formulas for the multiplicities of the\u0000weights of the spin module for the Clifford algebra of a Levi subalgebra in a\u0000complex semisimple Lie algebra. Our formulas involve only matrices and\u0000tableaux, and our techniques combine linear algebra, Lie theory, and\u0000combinatorics. Moreover, this suggests a relationship with complex nilpotent\u0000orbits. The case of the special linear Lie algebra $mathfrak{sl}(n,{mathbb\u0000C})$ is emphasized.","PeriodicalId":37836,"journal":{"name":"Communications in Mathematics","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49449176","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":"Minkowski's successive minima in convex and discrete geometry","authors":"I. Aliev, M. Henk","doi":"10.46298/cm.11155","DOIUrl":"https://doi.org/10.46298/cm.11155","url":null,"abstract":"In this short survey we want to present some of the impact of Minkowski's\u0000successive minima within Convex and Discrete Geometry. Originally related to\u0000the volume of an $o$-symmetric convex body, we point out relations of the\u0000successive minima to other functionals, as e.g., the lattice point enumerator\u0000or the intrinsic volumes and we present some old and new conjectures about\u0000them. Additionally, we discuss an application of successive minima to a version\u0000of Siegel's lemma.","PeriodicalId":37836,"journal":{"name":"Communications in Mathematics","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49090055","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":"On triviality of uniform Diophantine exponents of lattices","authors":"O. German","doi":"10.46298/cm.11137","DOIUrl":"https://doi.org/10.46298/cm.11137","url":null,"abstract":"In this paper we prove that uniform Diophantine exponents of lattices attain\u0000only trivial values.","PeriodicalId":37836,"journal":{"name":"Communications in Mathematics","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46522794","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":"On the number of lattice points in a ball","authors":"Jeffrey D. Vaaler","doi":"10.46298/cm.11119","DOIUrl":"https://doi.org/10.46298/cm.11119","url":null,"abstract":"We prove a fairly general inequality that estimates the number of lattice\u0000points in a ball of positive radius in general position in a Euclidean space.\u0000The bound is uniform over lattices induced by a matrix having a bounded\u0000operator norm.","PeriodicalId":37836,"journal":{"name":"Communications in Mathematics","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41773419","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":"Gradient estimates for a nonlinear elliptic equation on a smooth metric measure space","authors":"Xiaoshan Wang, Linfen Cao","doi":"10.46298/cm.10951","DOIUrl":"https://doi.org/10.46298/cm.10951","url":null,"abstract":"Let (M, g, e −f dv) be a smooth metric measure space. We consider local gradient estimates for positive solutions to the following elliptic equation ∆ f u + au log u + bu = 0 where a, b are two real constants and f be a smooth function defined on M. As an application, we obtain a Liouville type result for such equation in the case a < 0 under the m-dimensions Bakry-Émery Ricci curvature.","PeriodicalId":37836,"journal":{"name":"Communications in Mathematics","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41867795","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":"Cyclicity of the 2-class group of the first Hilbert 2-class field of some number fields","authors":"A. Azizi, M. Rezzougui, A. Zekhnini","doi":"10.46298/cm.10983","DOIUrl":"https://doi.org/10.46298/cm.10983","url":null,"abstract":"Let $mathds{k}$ be a real quadratic number field. Denote by\u0000$mathrm{Cl}_2(mathds{k})$ its $2$-class group and by $mathds{k}_2^{(1)}$\u0000(resp. $mathds{k}_2^{(2)}$) its first (resp. second) Hilbert $2$-class field.\u0000The aim of this paper is to study, for a real quadratic number field whose\u0000discriminant is divisible by one prime number congruent to $3$ modulo 4, the\u0000metacyclicity of $G=mathrm{Gal}(mathds{k}_2^{(2)}/mathds{k})$ and the\u0000cyclicity of $mathrm{Gal}(mathds{k}_2^{(2)}/mathds{k}_2^{(1)})$ whenever the\u0000rank of $mathrm{Cl}_2(mathds{k})$ is $2$, and the $4$-rank of\u0000$mathrm{Cl}_2(mathds{k})$ is $1$.","PeriodicalId":37836,"journal":{"name":"Communications in Mathematics","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46032598","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":"Certain Paracontact Metrics Satisfying the Critical Point Equation","authors":"D. Patra","doi":"10.46298/cm.10549","DOIUrl":"https://doi.org/10.46298/cm.10549","url":null,"abstract":"The aim of this paper is to study theCPE (Critical Point Equation) on some paracontact metric manifolds.First, we prove that if a para-Sasakian metric satisfies the CPE,then it is Einstein with constant scalar curvature -2n(2n+1). Next,we prove that if $(kappa,mu)$-paracontact metric satisfies theCPE, then it is locally isometric to the product of a flat$(n+1)$-dimensional manifold and $n$-dimensional manifold ofnegative constant curvature$-4$.","PeriodicalId":37836,"journal":{"name":"Communications in Mathematics","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41523437","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":"CONGRUENCES CONCERNING LEGENDRE POLYNOMIALS MODULO p^2","authors":"Aeran Kim","doi":"10.46298/cm.10767","DOIUrl":"https://doi.org/10.46298/cm.10767","url":null,"abstract":"In this article, we extend Z. H. Sun's congruences concerning Legendre polynomials P p−1 2 (x) to P p+1 2 (x) for odd prime p, which enables us to deduce some congruences resembling p+1 2 ∑ k=0 4pk + 4k 2 − 1 16 k (2k − 1) 2 (2k k)2 (mod p 2).\u0000 이 논문에서 우리는 Z. H. Sun의 르장드르 다항식의 합동식 P p−1 2 (x) 에서 P p+1 2 (x) (단, p는 소수) 까지를 이용해서 이 합동식과 비슷한 합동식 p+1 2 ∑ k=0 4pk + 4k 2 − 1 16 k (2k − 1) 2 (2k k)2 (mod p 2) 을 유도한다.","PeriodicalId":37836,"journal":{"name":"Communications in Mathematics","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43163509","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}