2024 spring
- Research seminar
2023 fall
- Foliations
2022 fall
- Groupoid C*-algebras
2022 spring
- K(K)-Theory
2021 fall
- Deformation Quantization and Index Theory


2023 spring
- Geometry and Operator ALgebras 2023
2022 fall
- NCG Day 2022

Noncommutative Geometry Reading Seminar

2022 Fall: Groupoid C*-algebras

In the 2022 fall semester, we were running a seminar on Groupoids and C*-algebras.

We followed the text book A Tool Kit for Groupoid C*-algebras in the first couple of talks and then turned to related topics including but not limited to semigroups, graphs, foliations, and twisted groupoids.

For more information, please contact y.ge@math.leidenuniv.nl

The note of this seminar can be found here. Last updated: 7.2.2024.


Snellius Building, Room 408 (mostly, see changes below), from 14:15 to 16:00.


Date Location Speaker Topic
9.13 Snellius 401 Yuezhao Li Motivations, Definitions, and Examples of Groupoids
9.20 Snellius 401 Yufan Ge Haar Systems and Convolution Algebras
9.27 No talk
10.4 Snellius 401 Jack Ekenstam Groupoid Actions: Part 1
10.11 Snellius 407/409 Bram Mesland Groupoid Actions: Part 2
10.18 Snellius 408 Dimitris Gerontogiannis The Equivalence Theorem
10.25 Snellius 408 Bram Mesland The Equivalence Theorem for Fell Bundles
11.1 Snellius 408 Middle Break: Problem Discussion
11.8 Snellius 408 Torstein Ulsnaes Induced Representations
11.15 Snellius 408 Malte Leimbach The Existence and Uniqueness of Haar Systems
11.22 Snellius 176 Jack Ekenstam Inverse Semigroups and Groupoids
11.29 Snellius 408 Yuezhao Li Tangent Groupoids and Index Theory
12.6 Snellius 408 Adam Rennie Groupoids Suck Slightly More Than Everything Else
12.13 Snellius 408 Yufan Ge Graph Groupoids and Doplicher-Roberts Algebras