Mikael R?rdam教授是澳门梅高美登录_澳门美高梅网址荣誉教授、丹麦皇家科学院院士、哥本哈根大学教授，国际算子代数研究领域的领军人物。R?rdam教授长期致力于算子代数、动力系统、几何群论、K-理论等领域的研究，其研究成果发表在Annals of Mathematics、Acta Mathematica等顶尖的数学杂志上，文章总引用率达2800多次。由于在C*-代数的结构和分类理论中的卓越工作，2006年，他应邀在马德里召开的第25届国际数学家大会（ICM）上作特邀报告。
In his study of the relative Dixmier property for von Neumann algebras and C*-algebras, Popa introduced a property of an automorphism, which can be thought of as a twisted Dixmier averaging property. We give an almost complete characterization of when an automorphism has this property. We further show how one can use this property to give much easier and more transparent proofs of a number of results on the inclusion of a C*-algebra into its crossed product C*-algebra by a group of automorphisms, assuming the automorphisms have averaging property.
