{"title":"Banach空间中度量投影的弱星可扩性、拟弱星近可扩性和连续性","authors":"Laiyou Bao, Suyalatu Wulede","doi":"10.7153/oam-2022-16-68","DOIUrl":null,"url":null,"abstract":". The relations between the w ∗ dentability and Chebyshev set or the continuity of metric projection operator are given. Let X ∗ be the conjugate space of Banach space X , the conditions of a point ( x ∗ , y ∗ ) on the unit sphere of product space X ∗ × X ∗ to be w ∗ denting point of closed unit ball of product space X ∗ × X ∗ are given. Also, a notion of quasi-w ∗ near dentability in conjugate space X ∗ is introduced and the relations between the quasi-w ∗ nearly denting point of closed unit ball of X ∗ and a certain slice of closed unit ball of X ∗ are given.","PeriodicalId":0,"journal":{"name":"","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Weak-star dentability, quasi-weak-star near dentability and continuity of metric projector in Banach spaces\",\"authors\":\"Laiyou Bao, Suyalatu Wulede\",\"doi\":\"10.7153/oam-2022-16-68\",\"DOIUrl\":null,\"url\":null,\"abstract\":\". The relations between the w ∗ dentability and Chebyshev set or the continuity of metric projection operator are given. Let X ∗ be the conjugate space of Banach space X , the conditions of a point ( x ∗ , y ∗ ) on the unit sphere of product space X ∗ × X ∗ to be w ∗ denting point of closed unit ball of product space X ∗ × X ∗ are given. Also, a notion of quasi-w ∗ near dentability in conjugate space X ∗ is introduced and the relations between the quasi-w ∗ nearly denting point of closed unit ball of X ∗ and a certain slice of closed unit ball of X ∗ are given.\",\"PeriodicalId\":0,\"journal\":{\"name\":\"\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":0.0,\"publicationDate\":\"2022-01-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"\",\"FirstCategoryId\":\"100\",\"ListUrlMain\":\"https://doi.org/10.7153/oam-2022-16-68\",\"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/10.7153/oam-2022-16-68","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
Weak-star dentability, quasi-weak-star near dentability and continuity of metric projector in Banach spaces
. The relations between the w ∗ dentability and Chebyshev set or the continuity of metric projection operator are given. Let X ∗ be the conjugate space of Banach space X , the conditions of a point ( x ∗ , y ∗ ) on the unit sphere of product space X ∗ × X ∗ to be w ∗ denting point of closed unit ball of product space X ∗ × X ∗ are given. Also, a notion of quasi-w ∗ near dentability in conjugate space X ∗ is introduced and the relations between the quasi-w ∗ nearly denting point of closed unit ball of X ∗ and a certain slice of closed unit ball of X ∗ are given.