Counting l-adic local systems over a curve

Time：Wed., 3:30-4:30 pm, May 28, 2025

Venue：B627, Shuangqing Complex Building A

Organizer：Hansheng Diao, Heng Du, Yueke Hu, Bin Xu, Yihang Zhu

Speaker：Hongjie Yu

BIMSA-YMSC Tsinghua Number Theory Seminar

Organizers：

Hansheng Diao, Heng Du, Yueke Hu, Bin Xu, Yihang Zhu

Speaker：

Hongjie Yu (MCM)

Time：

Wed., 3:30-4:30 pm, May 28, 2025

Venue：

B627, Shuangqing Complex Building A

Title：

Counting l-adic local systems over a curve

Abstract：

Given a punctured curve over a finite field, Deligne proposed counting irreducible geometric l-adic local systems with prescribed local ramification near each puncture, fixed by Frobenius pullback. This problem is closely related to determining a dimension formula for certain cuspidal automorphic forms over a function field. In this talk, I will present results in these directions and discuss some related questions arising in nearby areas.

DATEMay 27, 2025

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