群与图讨论班
Seminars on Groups and Graphs

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

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Time

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).

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Forthcoming Seminars

September 28th: 甘芸松 Yunsong Gan (Southern University of Science and Technology)
Asymptotic enumeration of graphical representations
Zoom: 262 780 8767 (passcode: gts2025)

The Next Seminar

Title: Asymptotic enumeration of graphical representations

Speaker: 甘芸松 Yunsong Gan (Southern University of Science and Technology)

Time: 16:00-17:00 (GMT+8), Sunday September 28th

Location: Zoom: 262 780 8767 (passcode: gts2025)

Abstract: Recent breakthroughs on symmetry of Cayley (di)graphs show that almost all finite Cayley (di)graphs have the smallest possible automorphism group. Extending the scope of these results, we enumerate (di)graphs admitting a fixed semiregular group of automorphisms with \(m\) orbits. Moreover, we consider the more intricate inquiry of prohibiting arcs within each orbit, where the special case \(m=2\) is known as the problem of finding Haar graphical representations (HGRs). We prove that the proportion of HGRs among Haar graphs of a finite nonabelian group approaches \(1\) as the group order grows. In this talk, we will also discuss some findings obtained by using graphical representations in the context of Mckay-Praeger Conjecture and Polycirculant Conjecture.

Other Confirmed Speakers

卢嘉平 Jiaping Lu (University of St. Andrews)

颜全福 Quanfu Yan (Peking University)

赵天骁 Tianxiao Zhao (Harbin Institute of Technology)

吴天泽 Tianze Wu (China Agricultural University)

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Current Organizers

陈俊彦 Junyan Chen (SUSTech)

尹富纲 Fu-Gang Yin (Beijing Jiaotong University)

张宝羽 Baoyu Zhang (University of Birmingham)

甘芸松 Yunsong Gan (Southern University of Science and Technology)

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