{"title":"复杂可表示矩阵的西尔维斯特-加莱类型定理","authors":"Jim Geelen, Matthew E. Kroeker","doi":"10.1007/s00454-024-00661-x","DOIUrl":null,"url":null,"abstract":"<p>The Sylvester–Gallai Theorem states that every rank-3 real-representable matroid has a two-point line. We prove that, for each <span>\\(k\\ge 2\\)</span>, every complex-representable matroid with rank at least <span>\\(4^{k-1}\\)</span> has a rank-<i>k</i> flat with exactly <i>k</i> points. For <span>\\(k=2\\)</span>, this is a well-known result due to Kelly, which we use in our proof. A similar result was proved earlier by Barak, Dvir, Wigderson, and Yehudayoff and later refined by Dvir, Saraf, and Wigderson, but we get slightly better bounds with a more elementary proof.</p>","PeriodicalId":0,"journal":{"name":"","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"A Sylvester–Gallai-Type Theorem for Complex-Representable Matroids\",\"authors\":\"Jim Geelen, Matthew E. Kroeker\",\"doi\":\"10.1007/s00454-024-00661-x\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p>The Sylvester–Gallai Theorem states that every rank-3 real-representable matroid has a two-point line. We prove that, for each <span>\\\\(k\\\\ge 2\\\\)</span>, every complex-representable matroid with rank at least <span>\\\\(4^{k-1}\\\\)</span> has a rank-<i>k</i> flat with exactly <i>k</i> points. For <span>\\\\(k=2\\\\)</span>, this is a well-known result due to Kelly, which we use in our proof. A similar result was proved earlier by Barak, Dvir, Wigderson, and Yehudayoff and later refined by Dvir, Saraf, and Wigderson, but we get slightly better bounds with a more elementary proof.</p>\",\"PeriodicalId\":0,\"journal\":{\"name\":\"\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":0.0,\"publicationDate\":\"2024-06-11\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"\",\"FirstCategoryId\":\"100\",\"ListUrlMain\":\"https://doi.org/10.1007/s00454-024-00661-x\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"","FirstCategoryId":"100","ListUrlMain":"https://doi.org/10.1007/s00454-024-00661-x","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
A Sylvester–Gallai-Type Theorem for Complex-Representable Matroids
The Sylvester–Gallai Theorem states that every rank-3 real-representable matroid has a two-point line. We prove that, for each \(k\ge 2\), every complex-representable matroid with rank at least \(4^{k-1}\) has a rank-k flat with exactly k points. For \(k=2\), this is a well-known result due to Kelly, which we use in our proof. A similar result was proved earlier by Barak, Dvir, Wigderson, and Yehudayoff and later refined by Dvir, Saraf, and Wigderson, but we get slightly better bounds with a more elementary proof.