{"title":"弱紧集上非扩张映射的不动点定理","authors":"Rashmi Malik, S. Rajesh","doi":"10.1007/s44146-023-00055-0","DOIUrl":null,"url":null,"abstract":"<div><p>In this paper, we prove that if <i>K</i> is a nonempty weakly compact set in a Banach space <i>X</i>, <span>\\(T: K \\rightarrow K\\)</span> is a nonexpansive map satisfying <span>\\(\\dfrac{x+Tx}{2} \\in K\\)</span> for all <span>\\(x \\in K\\)</span>, then <i>T</i> has a fixed point whenever <i>X</i> is uniformly rotund with respect to every <i>k</i>-dimensional subspace or <i>X</i> satisfies the <i>property</i> (<i>P</i>). These results improve the results of Veeramani and Radhakrishnan et al.</p></div>","PeriodicalId":46939,"journal":{"name":"ACTA SCIENTIARUM MATHEMATICARUM","volume":"89 1-2","pages":"81 - 92"},"PeriodicalIF":0.5000,"publicationDate":"2023-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s44146-023-00055-0.pdf","citationCount":"0","resultStr":"{\"title\":\"Fixed point theorems of nonexpansive mappings on weakly compact sets\",\"authors\":\"Rashmi Malik, S. Rajesh\",\"doi\":\"10.1007/s44146-023-00055-0\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>In this paper, we prove that if <i>K</i> is a nonempty weakly compact set in a Banach space <i>X</i>, <span>\\\\(T: K \\\\rightarrow K\\\\)</span> is a nonexpansive map satisfying <span>\\\\(\\\\dfrac{x+Tx}{2} \\\\in K\\\\)</span> for all <span>\\\\(x \\\\in K\\\\)</span>, then <i>T</i> has a fixed point whenever <i>X</i> is uniformly rotund with respect to every <i>k</i>-dimensional subspace or <i>X</i> satisfies the <i>property</i> (<i>P</i>). These results improve the results of Veeramani and Radhakrishnan et al.</p></div>\",\"PeriodicalId\":46939,\"journal\":{\"name\":\"ACTA SCIENTIARUM MATHEMATICARUM\",\"volume\":\"89 1-2\",\"pages\":\"81 - 92\"},\"PeriodicalIF\":0.5000,\"publicationDate\":\"2023-02-24\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://link.springer.com/content/pdf/10.1007/s44146-023-00055-0.pdf\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"ACTA SCIENTIARUM MATHEMATICARUM\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://link.springer.com/article/10.1007/s44146-023-00055-0\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"MATHEMATICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"ACTA SCIENTIARUM MATHEMATICARUM","FirstCategoryId":"1085","ListUrlMain":"https://link.springer.com/article/10.1007/s44146-023-00055-0","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"MATHEMATICS","Score":null,"Total":0}
Fixed point theorems of nonexpansive mappings on weakly compact sets
In this paper, we prove that if K is a nonempty weakly compact set in a Banach space X, \(T: K \rightarrow K\) is a nonexpansive map satisfying \(\dfrac{x+Tx}{2} \in K\) for all \(x \in K\), then T has a fixed point whenever X is uniformly rotund with respect to every k-dimensional subspace or X satisfies the property (P). These results improve the results of Veeramani and Radhakrishnan et al.