这是群论和图论方向的线上系列报告，我们希望能够促进国内外青年学者（博士生为主）在群论和图论研究上的交流。报告主题分布在（但不限于）以下研究方向：

- - 有限单群（有限单群分类定理，子群结构，共轭类等）
- - 置换群及其在组合结构上的作用
- - 线性代数群与李型群
- - 有限群的表示
- - 有限\(p\)-群
- - 图的谱理论

This is a platform for young group theorists and graph theorists (mostly PhD students) to talk about their research and related topics online. The topic can be anything related to group theory and graph theory, including but not limited to the following.

- - Finite simple groups (CFSG, subgroup structures and conjugacy classes)
- - Permutation groups and their actions on combinatorial structures
- - Linear algebraic groups and Lie type groups
- - Representations of finite groups
- - Finite \(p\)-groups
- - Spectral theory of graphs

一般地，系列报告定期于北京时间每周三下午16:00-17:00进行。

Our usual time is Wednesday 16:00-17:00 (GMT+8).

- June 17th: 曾青 Qing Zeng (Beijing Normal University)

Zoom 616 601 4311 (passcode: gts2024)

**Title: ****Weakly distance-regular digraphs with \(P\)-polynomial propertys
**

**Speaker: ** 曾青 (Beijing Normal University)

**Time: **16:00-17:00 (GMT+8), Wednesday June 17th

**Location: **Zoom: 616 601 4311 (passcode: gts2024)

**Abstract: **
Distance-regular graphs are an important class of graphs, which are equivalent to symmetric \(P\)-polynomial association schemes and have close connections to graph theory, finite geometry, coding theory, and design theory. As a directed version of distance-regular graphs, weakly distance-regular digraphs were proposed by Wang and Suzuki in 2003, which correspond to non-symmetric association schemes. In this thesis, we initiate studying weakly distance-regular digraphs with \(P\)-polynomial property, characterize weakly distance-regular digraphs whose attached schemes are \(P\)-polynomial, and classify all commutative weakly distance-regular digraphs whose underlying graphs are Hamming graphs, folded $n$-cubes, Doob graphs, and Johnson graphs, respectively.

- 陈俊彦 Junyan Chen (SUSTech)
- 丁兆宸 Zhaochen Ding (University of Auckland)
- 黄弘毅 Hong Yi Huang (University of Bristol)
- 尹富纲 Fu-Gang Yin (Central South University)

*The seminar is currently based at the Southern University of Science and Technology (SUSTech, 南方科技大学).*