Linear Algebra and its Applications最新文献

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Quasi-isometric liftings for operators similar to contractions
IF 1 3区 数学
Linear Algebra and its Applications Pub Date : 2025-01-10 DOI: 10.1016/j.laa.2025.01.006
Laurian Suciu, Andra-Maria Stoica
{"title":"Quasi-isometric liftings for operators similar to contractions","authors":"Laurian Suciu,&nbsp;Andra-Maria Stoica","doi":"10.1016/j.laa.2025.01.006","DOIUrl":"10.1016/j.laa.2025.01.006","url":null,"abstract":"<div><div>A class of quasi-isometric liftings for the operators <em>T</em> similar to contractions in Hilbert spaces <span><math><mi>H</mi></math></span> is studied. These liftings are isometric operators on their ranges, and are naturally induced by <em>T</em> and an invertible intertwiner of <em>T</em> with a contraction. In the case when <em>T</em> is a quasicontraction, meaning that <em>T</em> is contractive on its range, we obtain a quasi-isometric lifting on a space <span><math><mi>K</mi><mo>⊃</mo><mi>H</mi></math></span>, which is isometric on <span><math><mi>K</mi><mo>⊖</mo><mi>H</mi></math></span>. Some liftings with closed ranges, or even similar to quasinormal partial isometries are mentioned. Additionally, we study the isomorphic minimal quasi-isometric liftings for <em>T</em>, as well as the uniqueness property of such liftings. Our results show similarities with those from the isometric dilation theory for contractions, although our context is more general than that of the latter.</div></div>","PeriodicalId":18043,"journal":{"name":"Linear Algebra and its Applications","volume":"709 ","pages":"Pages 40-57"},"PeriodicalIF":1.0,"publicationDate":"2025-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143130287","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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
The triangulant
IF 1 3区 数学
Linear Algebra and its Applications Pub Date : 2025-01-10 DOI: 10.1016/j.laa.2025.01.004
Tamás Bencze , Péter E. Frenkel
{"title":"The triangulant","authors":"Tamás Bencze ,&nbsp;Péter E. Frenkel","doi":"10.1016/j.laa.2025.01.004","DOIUrl":"10.1016/j.laa.2025.01.004","url":null,"abstract":"<div><div>We introduce the triangulant of two matrices, and relate it to the existence of orthogonal eigenvectors. We also use it for a new characterization of mutually unbiased bases. Generalizing the notion, we introduce higher order triangulants of two matrices, and relate them to the existence of nontrivially intersecting invariant subspaces of complementary dimensions.</div></div>","PeriodicalId":18043,"journal":{"name":"Linear Algebra and its Applications","volume":"709 ","pages":"Pages 92-110"},"PeriodicalIF":1.0,"publicationDate":"2025-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143130289","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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
Quadratic embedding constants of fan graphs and graph joins
IF 1 3区 数学
Linear Algebra and its Applications Pub Date : 2025-01-06 DOI: 10.1016/j.laa.2025.01.001
Wojciech Młotkowski , Nobuaki Obata
{"title":"Quadratic embedding constants of fan graphs and graph joins","authors":"Wojciech Młotkowski ,&nbsp;Nobuaki Obata","doi":"10.1016/j.laa.2025.01.001","DOIUrl":"10.1016/j.laa.2025.01.001","url":null,"abstract":"<div><div>We derive a general formula for the quadratic embedding constant of a graph join <span><math><msub><mrow><mover><mrow><mi>K</mi></mrow><mrow><mo>¯</mo></mrow></mover></mrow><mrow><mi>m</mi></mrow></msub><mo>+</mo><mi>G</mi></math></span>, where <span><math><msub><mrow><mover><mrow><mi>K</mi></mrow><mrow><mo>¯</mo></mrow></mover></mrow><mrow><mi>m</mi></mrow></msub></math></span> is the empty graph on <span><math><mi>m</mi><mo>≥</mo><mn>1</mn></math></span> vertices and <em>G</em> is an arbitrary graph. Applying our formula to a fan graph <span><math><msub><mrow><mi>K</mi></mrow><mrow><mn>1</mn></mrow></msub><mo>+</mo><msub><mrow><mi>P</mi></mrow><mrow><mi>n</mi></mrow></msub></math></span>, where <span><math><msub><mrow><mi>K</mi></mrow><mrow><mn>1</mn></mrow></msub><mo>=</mo><msub><mrow><mover><mrow><mi>K</mi></mrow><mrow><mo>¯</mo></mrow></mover></mrow><mrow><mn>1</mn></mrow></msub></math></span> is the singleton graph and <span><math><msub><mrow><mi>P</mi></mrow><mrow><mi>n</mi></mrow></msub></math></span> is the path on <span><math><mi>n</mi><mo>≥</mo><mn>1</mn></math></span> vertices, we show that <span><math><mrow><mi>QEC</mi></mrow><mo>(</mo><msub><mrow><mi>K</mi></mrow><mrow><mn>1</mn></mrow></msub><mo>+</mo><msub><mrow><mi>P</mi></mrow><mrow><mi>n</mi></mrow></msub><mo>)</mo><mo>=</mo><mo>−</mo><msub><mrow><mover><mrow><mi>α</mi></mrow><mrow><mo>˜</mo></mrow></mover></mrow><mrow><mi>n</mi></mrow></msub><mo>−</mo><mn>2</mn></math></span>, where <span><math><msub><mrow><mover><mrow><mi>α</mi></mrow><mrow><mo>˜</mo></mrow></mover></mrow><mrow><mi>n</mi></mrow></msub></math></span> is the minimal zero of a new polynomial <span><math><msub><mrow><mi>Φ</mi></mrow><mrow><mi>n</mi></mrow></msub><mo>(</mo><mi>x</mi><mo>)</mo></math></span> related to Chebyshev polynomials of the second kind. Moreover, for an even <em>n</em> we have <span><math><msub><mrow><mover><mrow><mi>α</mi></mrow><mrow><mo>˜</mo></mrow></mover></mrow><mrow><mi>n</mi></mrow></msub><mo>=</mo><mi>min</mi><mo>⁡</mo><mrow><mi>ev</mi></mrow><mo>(</mo><msub><mrow><mi>A</mi></mrow><mrow><mi>n</mi></mrow></msub><mo>)</mo></math></span>, where the right-hand side is the minimal eigenvalue of the adjacency matrix <span><math><msub><mrow><mi>A</mi></mrow><mrow><mi>n</mi></mrow></msub></math></span> of <span><math><msub><mrow><mi>P</mi></mrow><mrow><mi>n</mi></mrow></msub></math></span>. For an odd <em>n</em> we show that <span><math><mi>min</mi><mo>⁡</mo><mrow><mi>ev</mi></mrow><mo>(</mo><msub><mrow><mi>A</mi></mrow><mrow><mi>n</mi><mo>+</mo><mn>1</mn></mrow></msub><mo>)</mo><mo>≤</mo><msub><mrow><mover><mrow><mi>α</mi></mrow><mrow><mo>˜</mo></mrow></mover></mrow><mrow><mi>n</mi></mrow></msub><mo>&lt;</mo><mi>min</mi><mo>⁡</mo><mrow><mi>ev</mi></mrow><mo>(</mo><msub><mrow><mi>A</mi></mrow><mrow><mi>n</mi></mrow></msub><mo>)</mo></math></span>.</div></div>","PeriodicalId":18043,"journal":{"name":"Linear Algebra and its Applications","volume":"709 ","pages":"Pages 58-91"},"PeriodicalIF":1.0,"publicationDate":"2025-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143130286","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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
Threshold graphs, Kemeny's constant, and related random walk parameters
IF 1 3区 数学
Linear Algebra and its Applications Pub Date : 2025-01-06 DOI: 10.1016/j.laa.2024.12.022
Jane Breen , Sooyeong Kim , Alexander Low Fung , Amy Mann , Andrei A. Parfeni , Giovanni Tedesco
{"title":"Threshold graphs, Kemeny's constant, and related random walk parameters","authors":"Jane Breen ,&nbsp;Sooyeong Kim ,&nbsp;Alexander Low Fung ,&nbsp;Amy Mann ,&nbsp;Andrei A. Parfeni ,&nbsp;Giovanni Tedesco","doi":"10.1016/j.laa.2024.12.022","DOIUrl":"10.1016/j.laa.2024.12.022","url":null,"abstract":"<div><div>Kemeny's constant measures how fast a random walker moves around in a graph. Expressions for Kemeny's constant can be quite involved, and for this reason, many lines of research focus on graphs with structure that makes them amenable to more in-depth study (for example, regular graphs, acyclic graphs, and 1-connected graphs). In this article, we study Kemeny's constant for random walks on threshold graphs, which are an interesting family of graphs with properties that make examining Kemeny's constant difficult; that is, they are usually not regular, not acyclic, and not 1-connected. This article is a showcase of various techniques for calculating Kemeny's constant and related random walk parameters for graphs. We establish explicit formulae for <span><math><mi>K</mi><mo>(</mo><mi>G</mi><mo>)</mo></math></span> in terms of the construction code of a threshold graph, and completely determine the ordering of the accessibility indices of vertices in threshold graphs.</div></div>","PeriodicalId":18043,"journal":{"name":"Linear Algebra and its Applications","volume":"709 ","pages":"Pages 284-313"},"PeriodicalIF":1.0,"publicationDate":"2025-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143130256","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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
Symmetric doubly stochastic inverse eigenvalue problem for odd sizes
IF 1 3区 数学
Linear Algebra and its Applications Pub Date : 2024-12-31 DOI: 10.1016/j.laa.2024.12.020
Mohadese Raeisi Sarkhoni , Hossein Momenaee Kermani , Azim Rivaz
{"title":"Symmetric doubly stochastic inverse eigenvalue problem for odd sizes","authors":"Mohadese Raeisi Sarkhoni ,&nbsp;Hossein Momenaee Kermani ,&nbsp;Azim Rivaz","doi":"10.1016/j.laa.2024.12.020","DOIUrl":"10.1016/j.laa.2024.12.020","url":null,"abstract":"<div><div>The symmetric doubly stochastic inverse eigenvalue problem seeks to determine the necessary and sufficient conditions for a real list of eigenvalues to be realized by a symmetric doubly stochastic matrix. Nader et al. (2019) <span><span>[15]</span></span>, established that for odd integers <em>n</em> a list of the form <span><math><mi>σ</mi><mo>=</mo><mo>(</mo><mn>1</mn><mo>,</mo><msub><mrow><mi>λ</mi></mrow><mrow><mn>2</mn></mrow></msub><mo>,</mo><msub><mrow><mi>λ</mi></mrow><mrow><mn>3</mn></mrow></msub><mo>,</mo><mo>.</mo><mo>.</mo><mo>.</mo><mo>,</mo><msub><mrow><mi>λ</mi></mrow><mrow><msub><mrow></mrow><mrow><mi>n</mi><mo>−</mo><mn>1</mn></mrow></msub></mrow></msub><mo>,</mo><mo>−</mo><mn>1</mn><mo>)</mo></math></span> with <span><math><mo>|</mo><msub><mrow><mi>λ</mi></mrow><mrow><mi>i</mi></mrow></msub><mo>|</mo><mo>&lt;</mo><mn>1</mn></math></span> for <span><math><mi>i</mi><mo>=</mo><mn>2</mn><mo>,</mo><mo>.</mo><mo>.</mo><mo>.</mo><mo>,</mo><mi>n</mi><mo>−</mo><mn>1</mn></math></span> cannot be the spectrum of any <span><math><mi>n</mi><mo>×</mo><mi>n</mi></math></span> doubly stochastic matrix. This implies that the list <span><math><mi>σ</mi><mo>=</mo><mo>(</mo><mn>1</mn><mo>,</mo><mn>0</mn><mo>,</mo><mo>.</mo><mo>.</mo><mo>.</mo><mo>,</mo><mn>0</mn><mo>,</mo><mo>−</mo><mn>1</mn><mo>)</mo></math></span> is also unrealizable.</div><div>This paper extends these findings by proving that for odd <em>n</em> and <span><math><msub><mrow><mi>λ</mi></mrow><mrow><msub><mrow></mrow><mrow><mi>n</mi></mrow></msub></mrow></msub><mo>∈</mo><mo>[</mo><mo>−</mo><mn>1</mn><mo>,</mo><mo>−</mo><mfrac><mrow><mi>n</mi><mo>−</mo><mn>1</mn></mrow><mrow><mi>n</mi></mrow></mfrac><mo>)</mo></math></span>, the list <span><math><mo>(</mo><mn>1</mn><mo>,</mo><mn>0</mn><mo>,</mo><mo>.</mo><mo>.</mo><mo>.</mo><mo>,</mo><mn>0</mn><mo>,</mo><msub><mrow><mi>λ</mi></mrow><mrow><msub><mrow></mrow><mrow><mi>n</mi></mrow></msub></mrow></msub><mo>)</mo></math></span> cannot be the spectrum of a symmetric doubly stochastic matrix. We demonstrate that for odd <em>n</em> the list <span><math><mi>σ</mi><mo>=</mo><mo>(</mo><mn>1</mn><mo>,</mo><mn>0</mn><mo>,</mo><mo>.</mo><mo>.</mo><mo>.</mo><mo>,</mo><mn>0</mn><mo>,</mo><mo>−</mo><mfrac><mrow><mi>n</mi><mo>−</mo><mn>1</mn></mrow><mrow><mi>n</mi></mrow></mfrac><mo>)</mo></math></span>, is indeed realizable as the spectrum of a symmetric doubly stochastic matrix.</div><div>Furthermore, we utilize our methodology to derive new sufficient conditions for the existence of <span><math><mi>n</mi><mo>×</mo><mi>n</mi></math></span> symmetric doubly stochastic matrices with a prescribed list of eigenvalues. This leads to a condition for the existence of symmetric doubly stochastic matrices with a normalized Suleimanova spectrum. The paper concludes with additional partial results and illustrative examples.</div></div>","PeriodicalId":18043,"journal":{"name":"Linear Algebra and its Applications","volume":"708 ","pages":"Pages 594-607"},"PeriodicalIF":1.0,"publicationDate":"2024-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143164638","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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
Linear bijective maps preserving invertibility on pairs of similar matrices
IF 1 3区 数学
Linear Algebra and its Applications Pub Date : 2024-12-31 DOI: 10.1016/j.laa.2024.12.021
Constantin Costara
{"title":"Linear bijective maps preserving invertibility on pairs of similar matrices","authors":"Constantin Costara","doi":"10.1016/j.laa.2024.12.021","DOIUrl":"10.1016/j.laa.2024.12.021","url":null,"abstract":"<div><div>Let <span><math><mi>n</mi><mo>≥</mo><mn>2</mn></math></span> be a natural number, and denote by <span><math><msub><mrow><mi>M</mi></mrow><mrow><mi>n</mi></mrow></msub></math></span> the space of all <span><math><mi>n</mi><mo>×</mo><mi>n</mi></math></span> matrices over the complex field. In this paper, we characterize linear bijective maps <em>φ</em> on <span><math><msub><mrow><mi>M</mi></mrow><mrow><mi>n</mi></mrow></msub></math></span> having the property that if <span><math><mi>A</mi><mo>,</mo><mi>B</mi><mo>∈</mo><msub><mrow><mi>M</mi></mrow><mrow><mi>n</mi></mrow></msub></math></span> are similar matrices and <span><math><mi>φ</mi><mo>(</mo><mi>A</mi><mo>)</mo></math></span> is invertible, then <span><math><mi>φ</mi><mo>(</mo><mi>B</mi><mo>)</mo></math></span> is invertible as well.</div></div>","PeriodicalId":18043,"journal":{"name":"Linear Algebra and its Applications","volume":"708 ","pages":"Pages 585-593"},"PeriodicalIF":1.0,"publicationDate":"2024-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143165108","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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
Asymptotic spectral properties and preconditioning of an approximated nonlocal Helmholtz equation with fractional Laplacian and variable coefficient wave number μ
IF 1 3区 数学
Linear Algebra and its Applications Pub Date : 2024-12-27 DOI: 10.1016/j.laa.2024.12.015
Andrea Adriani , Rosita L. Sormani , Cristina Tablino-Possio , Rolf Krause , Stefano Serra-Capizzano
{"title":"Asymptotic spectral properties and preconditioning of an approximated nonlocal Helmholtz equation with fractional Laplacian and variable coefficient wave number μ","authors":"Andrea Adriani ,&nbsp;Rosita L. Sormani ,&nbsp;Cristina Tablino-Possio ,&nbsp;Rolf Krause ,&nbsp;Stefano Serra-Capizzano","doi":"10.1016/j.laa.2024.12.015","DOIUrl":"10.1016/j.laa.2024.12.015","url":null,"abstract":"<div><div>The current study investigates the asymptotic spectral properties of a finite difference approximation of nonlocal Helmholtz equations with a fractional Laplacian and a variable coefficient wave number <em>μ</em>, as it occurs when considering a wave propagation in complex media, characterized by nonlocal interactions and spatially varying wave speeds. More specifically, by using tools from Toeplitz and generalized locally Toeplitz theory, the present research delves into the spectral analysis of nonpreconditioned and preconditioned matrix sequences, with the main novelty regarding a complete picture of the case where <span><math><mi>μ</mi><mo>=</mo><mi>μ</mi><mo>(</mo><mi>x</mi><mo>,</mo><mi>y</mi><mo>)</mo></math></span> is nonconstant. We report numerical evidence supporting the theoretical findings. Finally, open problems and potential extensions in various directions are presented and briefly discussed.</div></div>","PeriodicalId":18043,"journal":{"name":"Linear Algebra and its Applications","volume":"708 ","pages":"Pages 551-584"},"PeriodicalIF":1.0,"publicationDate":"2024-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143165107","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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
Some stability results for spectral extremal problems of graphs with bounded matching number
IF 1 3区 数学
Linear Algebra and its Applications Pub Date : 2024-12-20 DOI: 10.1016/j.laa.2024.12.018
Shixia Jiang , Xiying Yuan , Yanni Zhai
{"title":"Some stability results for spectral extremal problems of graphs with bounded matching number","authors":"Shixia Jiang ,&nbsp;Xiying Yuan ,&nbsp;Yanni Zhai","doi":"10.1016/j.laa.2024.12.018","DOIUrl":"10.1016/j.laa.2024.12.018","url":null,"abstract":"<div><div>For a set of graphs <span><math><mi>H</mi></math></span>, a graph is called <span><math><mi>H</mi></math></span>-free if it does not contain any member of <span><math><mi>H</mi></math></span> as a subgraph. The maximum value of spectral radius among all <span><math><mi>H</mi></math></span>-free graphs of order <em>n</em> is denoted by <span><math><mrow><mi>spex</mi></mrow><mo>(</mo><mi>n</mi><mo>,</mo><mi>H</mi><mo>)</mo></math></span>, and the set of corresponding extremal graphs is denoted by <span><math><mrow><mi>SPEX</mi></mrow><mo>(</mo><mi>n</mi><mo>,</mo><mi>H</mi><mo>)</mo></math></span>. In this paper, we give a stability result for graphs in <span><math><mrow><mi>SPEX</mi></mrow><mo>(</mo><mi>n</mi><mo>,</mo><mi>H</mi><mo>)</mo></math></span> when <span><math><mrow><mi>spex</mi></mrow><mo>(</mo><mi>n</mi><mo>,</mo><mi>H</mi><mo>)</mo><mo>≥</mo><msqrt><mrow><mi>s</mi><mo>(</mo><mi>n</mi><mo>−</mo><mi>s</mi><mo>)</mo></mrow></msqrt></math></span> and <span><math><mrow><mi>ex</mi></mrow><mo>(</mo><mi>n</mi><mo>,</mo><mi>H</mi><mo>)</mo><mo>≤</mo><mi>s</mi><mi>n</mi></math></span>. As an application, we may give some characterizations for the graphs in <span><math><mrow><mi>SPEX</mi></mrow><mo>(</mo><mi>n</mi><mo>,</mo><mo>{</mo><msub><mrow><mi>M</mi></mrow><mrow><mi>s</mi><mo>+</mo><mn>1</mn></mrow></msub><mo>,</mo><mi>H</mi><mo>}</mo><mo>)</mo></math></span>, where <span><math><msub><mrow><mi>M</mi></mrow><mrow><mi>s</mi><mo>+</mo><mn>1</mn></mrow></msub></math></span> is a matching with <span><math><mi>s</mi><mo>+</mo><mn>1</mn></math></span> edges and <em>H</em> is any non-bipartite graph.</div></div>","PeriodicalId":18043,"journal":{"name":"Linear Algebra and its Applications","volume":"708 ","pages":"Pages 513-524"},"PeriodicalIF":1.0,"publicationDate":"2024-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143165105","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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
Remarks on generating families of matrix algebras of small orders
IF 1 3区 数学
Linear Algebra and its Applications Pub Date : 2024-12-20 DOI: 10.1016/j.laa.2024.12.013
Yaroslav Shitov
{"title":"Remarks on generating families of matrix algebras of small orders","authors":"Yaroslav Shitov","doi":"10.1016/j.laa.2024.12.013","DOIUrl":"10.1016/j.laa.2024.12.013","url":null,"abstract":"<div><div>Let <span><math><mi>n</mi><mo>⩽</mo><mn>7</mn></math></span>, and let <em>S</em> be a family of <span><math><mi>n</mi><mo>×</mo><mi>n</mi></math></span> matrices over a field <span><math><mi>F</mi></math></span>. I prove that the <span><math><mi>F</mi></math></span>-linear span of<span><span><span><math><msup><mrow><mo>(</mo><mi>S</mi><mo>∪</mo><mo>{</mo><mrow><mi>Id</mi></mrow><mo>}</mo><mo>)</mo></mrow><mrow><mn>2</mn><mi>n</mi><mo>−</mo><mn>2</mn></mrow></msup></math></span></span></span> is the algebra generated by <em>S</em>.</div></div>","PeriodicalId":18043,"journal":{"name":"Linear Algebra and its Applications","volume":"708 ","pages":"Pages 458-462"},"PeriodicalIF":1.0,"publicationDate":"2024-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143165101","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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
Fractional perfect matching and distance spectral radius in graphs
IF 1 3区 数学
Linear Algebra and its Applications Pub Date : 2024-12-19 DOI: 10.1016/j.laa.2024.12.016
Lei Zhang , Yaoping Hou , Haizhen Ren
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