## 2021年曲阜师范大学算子代数研讨会学术报告预告

1. 蒋春澜教授， 河北师范大学

2. 侯晋川教授，太原理工大学

and the monogamy relation for continuous-variable systems

3. 吉国兴教授 陕西师范大学

4. 纪友清教授，吉林大学

5. 丁宣浩教授，重庆工商大学

6. 吴志强教授，南开大学

For an ortho-set, a canonical complete ortholattice is constructed. Conversely, every complete ortholattice comes from an ortho-set in this way. Hence, the theory of ortho-sets captures almost everything about quantum logics.

For a quantum system modeled by the self-adjoint part $B_\mathrm{sa}$ of a $C^*$-algebra $B$, we also introduce a semi-classical object'' called the Gelfand spectrum. It is the ortho-set, $P(B)$, of pure states of $B$ equipped with an ortho-topology'', which is a collection of subsets of $P(B)$, defined via a hull-kernel construction with respects to closed left ideals of $B$.

We establish a generalization of the Gelfand theorem by showing that a bijection between the Gelfand spectra of two quantum systems that preserves the respective ortho-topologies is induced by a Jordan isomorphism between the self-adjoint parts of the underlying $C^*$-algebras (i.e. an isomorphism of the quantum systems), when the underlying $C^*$-algebras satisfy a mild condition.

7. 刘锐教授，南开大学

8. 曹小红教授，陕西师范大学

9. 齐霄霏教授，山西大学

10. 孟庆副教授 曲阜师范大学

coincide with that of the reduced one. We give a complete description for the reduced crossed product to have strong property T. We also give a characterization of the amenability of a locally compact group and a characterization of the inner amenability of an ICC group, both in terms of property T of certain reduced crossed products. Moreover, we introduce Hilbert A -module property T and show that the action has property T if and only if the reduced crossed product has Hilbert A -module property T.

11. 房军生教授 河北师范大学

Title: Sums of projections in semifinite factors

Abstract: Which positive operators in a factor von Neumann algebra can be written as sums of projections? This question is studied by Victor Kaftal, Ping Wong Ng, and Shuang Zhang. They obtained beautiful results on the question. In this talk we report some new progress on the question. This is joint work with Xinyan Cao and Zhaolin Yao.

12. 石瑞副教授，大连理工大学

13. 李磊副教授， 南开大学

14. 麻振华副教授， 河北建筑工程学院

15. 吴常晖博士， 曲阜师范大学

16. 羌湘琦博士 扬州大学

systems

and (strongly) asymptotic conjugacy for expansive systems, and characterize them in terms of the transformation groupoids, the principal groupoids coming from the local conjugacy relations and the semi-direct product groupoids of the principal groupoids by the canonical group actions, together with their associated reduced groupoid C*-algebras. We also give some generalization to continuous orbit equivalence up to etale equivalence relation.