{"title":"奥尔利奇-波赫纳序列空间中的弱紧凑集","authors":"Wanzhong Gong, Siyu Shi, Zhongrui Shi","doi":"10.1002/mana.202400058","DOIUrl":null,"url":null,"abstract":"<p>In this work, we give three kinds of criteria for weak sets in Orlicz–Bochner sequence spaces <span></span><math>\n <semantics>\n <mrow>\n <msub>\n <mi>l</mi>\n <mrow>\n <mo>(</mo>\n <mi>Φ</mi>\n <mo>)</mo>\n </mrow>\n </msub>\n <mrow>\n <mo>(</mo>\n <mi>X</mi>\n <mo>)</mo>\n </mrow>\n </mrow>\n <annotation>$l_{(\\Phi)}(X)$</annotation>\n </semantics></math> without constraints, conditions posited in each criterion are necessary and sufficient. As an application, we give criteria for weak sets in Orlicz sequence spaces. Well-known conclusions are exhibited once more, such as Schur's theorem, Banach–Alaoglu's theorem, and the boundedly compact principle of finite dimension space. The results obtained show that the weak compactness may not be extrapolated straightforwardly from <span></span><math>\n <semantics>\n <mi>X</mi>\n <annotation>$X$</annotation>\n </semantics></math> to <span></span><math>\n <semantics>\n <mrow>\n <msub>\n <mi>l</mi>\n <mrow>\n <mo>(</mo>\n <mi>Φ</mi>\n <mo>)</mo>\n </mrow>\n </msub>\n <mrow>\n <mo>(</mo>\n <mi>X</mi>\n <mo>)</mo>\n </mrow>\n </mrow>\n <annotation>$l_{(\\Phi)}(X)$</annotation>\n </semantics></math>, for example, <span></span><math>\n <semantics>\n <mrow>\n <msub>\n <mi>l</mi>\n <mi>∞</mi>\n </msub>\n <mrow>\n <mo>(</mo>\n <mi>X</mi>\n <mo>)</mo>\n </mrow>\n </mrow>\n <annotation>$l_{\\infty }(X)$</annotation>\n </semantics></math>.</p>","PeriodicalId":49853,"journal":{"name":"Mathematische Nachrichten","volume":"297 9","pages":"3313-3333"},"PeriodicalIF":0.8000,"publicationDate":"2024-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Weakly compact sets in Orlicz–Bochner sequence spaces\",\"authors\":\"Wanzhong Gong, Siyu Shi, Zhongrui Shi\",\"doi\":\"10.1002/mana.202400058\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p>In this work, we give three kinds of criteria for weak sets in Orlicz–Bochner sequence spaces <span></span><math>\\n <semantics>\\n <mrow>\\n <msub>\\n <mi>l</mi>\\n <mrow>\\n <mo>(</mo>\\n <mi>Φ</mi>\\n <mo>)</mo>\\n </mrow>\\n </msub>\\n <mrow>\\n <mo>(</mo>\\n <mi>X</mi>\\n <mo>)</mo>\\n </mrow>\\n </mrow>\\n <annotation>$l_{(\\\\Phi)}(X)$</annotation>\\n </semantics></math> without constraints, conditions posited in each criterion are necessary and sufficient. As an application, we give criteria for weak sets in Orlicz sequence spaces. Well-known conclusions are exhibited once more, such as Schur's theorem, Banach–Alaoglu's theorem, and the boundedly compact principle of finite dimension space. The results obtained show that the weak compactness may not be extrapolated straightforwardly from <span></span><math>\\n <semantics>\\n <mi>X</mi>\\n <annotation>$X$</annotation>\\n </semantics></math> to <span></span><math>\\n <semantics>\\n <mrow>\\n <msub>\\n <mi>l</mi>\\n <mrow>\\n <mo>(</mo>\\n <mi>Φ</mi>\\n <mo>)</mo>\\n </mrow>\\n </msub>\\n <mrow>\\n <mo>(</mo>\\n <mi>X</mi>\\n <mo>)</mo>\\n </mrow>\\n </mrow>\\n <annotation>$l_{(\\\\Phi)}(X)$</annotation>\\n </semantics></math>, for example, <span></span><math>\\n <semantics>\\n <mrow>\\n <msub>\\n <mi>l</mi>\\n <mi>∞</mi>\\n </msub>\\n <mrow>\\n <mo>(</mo>\\n <mi>X</mi>\\n <mo>)</mo>\\n </mrow>\\n </mrow>\\n <annotation>$l_{\\\\infty }(X)$</annotation>\\n </semantics></math>.</p>\",\"PeriodicalId\":49853,\"journal\":{\"name\":\"Mathematische Nachrichten\",\"volume\":\"297 9\",\"pages\":\"3313-3333\"},\"PeriodicalIF\":0.8000,\"publicationDate\":\"2024-06-16\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Mathematische Nachrichten\",\"FirstCategoryId\":\"100\",\"ListUrlMain\":\"https://onlinelibrary.wiley.com/doi/10.1002/mana.202400058\",\"RegionNum\":3,\"RegionCategory\":\"数学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"MATHEMATICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Mathematische Nachrichten","FirstCategoryId":"100","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1002/mana.202400058","RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"MATHEMATICS","Score":null,"Total":0}
引用次数: 0
摘要
在这项工作中,我们给出了奥立兹-波赫纳序列空间 l ( Φ ) ( X ) $l_{(\Phi)}(X)$ 中三种无约束弱集的判据,每个判据中提出的条件都是必要的和充分的。作为应用,我们给出了奥立兹序列空间中弱集的判据。我们再次展示了众所周知的结论,如舒尔定理、巴纳赫-阿洛格鲁定理和有限维空间的有界紧凑原理。所得到的结果表明,弱紧凑性可能无法从 X $X$ 直接外推到 l ( Φ ) ( X ) $l_{(\Phi)}(X)$ ,例如,l ∞ ( X ) $l_{\infty }(X)$ 。
Weakly compact sets in Orlicz–Bochner sequence spaces
In this work, we give three kinds of criteria for weak sets in Orlicz–Bochner sequence spaces without constraints, conditions posited in each criterion are necessary and sufficient. As an application, we give criteria for weak sets in Orlicz sequence spaces. Well-known conclusions are exhibited once more, such as Schur's theorem, Banach–Alaoglu's theorem, and the boundedly compact principle of finite dimension space. The results obtained show that the weak compactness may not be extrapolated straightforwardly from to , for example, .
期刊介绍:
Mathematische Nachrichten - Mathematical News publishes original papers on new results and methods that hold prospect for substantial progress in mathematics and its applications. All branches of analysis, algebra, number theory, geometry and topology, flow mechanics and theoretical aspects of stochastics are given special emphasis. Mathematische Nachrichten is indexed/abstracted in Current Contents/Physical, Chemical and Earth Sciences; Mathematical Review; Zentralblatt für Mathematik; Math Database on STN International, INSPEC; Science Citation Index