{"title":"素 C* 结构上有限群的外作用","authors":"Costel Peligrad","doi":"arxiv-2408.02510","DOIUrl":null,"url":null,"abstract":"An action of a compact, in particular finite group on a C*-algebra is called\nproperly outer if no automorphism of the group that is distinct from identity\nis implemented by a unitary element of the algebra of local multipliers of the\nC*-algebra and strictly outer if the commutant of the algebra in the algebra of\nlocal mutipliers of the cross product consists of scalars [11]. In [11, Theorem\n11] I proved that for finite groups and prime C*-algebras (not necessarily\nseparable), the two notions are equivalent. I also proved that for finite\nabelian groups this is equivalent to other relevant properties of the action\n[11 Theorem 14]. In this paper I add other properties to the list in [11,\nTheorem 14].","PeriodicalId":501114,"journal":{"name":"arXiv - MATH - Operator Algebras","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"2024-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Outer actions of finite groups on prime C*-algebras\",\"authors\":\"Costel Peligrad\",\"doi\":\"arxiv-2408.02510\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"An action of a compact, in particular finite group on a C*-algebra is called\\nproperly outer if no automorphism of the group that is distinct from identity\\nis implemented by a unitary element of the algebra of local multipliers of the\\nC*-algebra and strictly outer if the commutant of the algebra in the algebra of\\nlocal mutipliers of the cross product consists of scalars [11]. In [11, Theorem\\n11] I proved that for finite groups and prime C*-algebras (not necessarily\\nseparable), the two notions are equivalent. I also proved that for finite\\nabelian groups this is equivalent to other relevant properties of the action\\n[11 Theorem 14]. In this paper I add other properties to the list in [11,\\nTheorem 14].\",\"PeriodicalId\":501114,\"journal\":{\"name\":\"arXiv - MATH - Operator Algebras\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2024-08-05\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"arXiv - MATH - Operator Algebras\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/arxiv-2408.02510\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"arXiv - MATH - Operator Algebras","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/arxiv-2408.02510","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
Outer actions of finite groups on prime C*-algebras
An action of a compact, in particular finite group on a C*-algebra is called
properly outer if no automorphism of the group that is distinct from identity
is implemented by a unitary element of the algebra of local multipliers of the
C*-algebra and strictly outer if the commutant of the algebra in the algebra of
local mutipliers of the cross product consists of scalars [11]. In [11, Theorem
11] I proved that for finite groups and prime C*-algebras (not necessarily
separable), the two notions are equivalent. I also proved that for finite
abelian groups this is equivalent to other relevant properties of the action
[11 Theorem 14]. In this paper I add other properties to the list in [11,
Theorem 14].