## 作用素環セミナー

2012年 　 2月 8日 14時 30分 ～ 2012年 　 2月 8日 17時 20分

N. Christopher Phillips (University of Oregon)/泉正己 (京都大学)/佐藤康彦 (京都大学)

14:30-15:20

タイトル: Towards the classification of actions of finite groups on purely infinite simple C*-algebras
アブストラクト:
UCT Kirchberg algebras (purely infinite simple separable nuclear
C*-algebras satisfying the Universal Coefficient Theorem) are known
to be determined up to isomorphism by K-theoretic invariants.
More recently, a K-theoretic classification has been given for actions of
finite groups on such algebras satisfying the Rokhlin property.
We describe progress toward such a classification under the much less
restrictive condition that the action be pointwise outer.

We are aiming for two results. The first is that, for pointwise outer
actions of arbitrary finite groups, KK_G-equivalence implies conjugacy.
The second is that, when the group is cyclic of prime order and the
actions are in a suitable bootstrap class, isomorphism of certain
equivariant K-theoretical invariants implies conjugacy.

In the second talk, depending on the interest of the audience, I could
give some extremely preliminary information about actions of infinite
compact groups.

15：30-16:20

タイトル: Poly-Z group actions on Kirchberg algebras

16:30-17:20

タイトル: Strict comparison and Z-absorption of nuclear C*-algebras