The seminar will meet at 4:00–5:00 pm, Wednesday (almost) every week during semesters, in the lecture room of IASM (East 7 Bldg, Zijingang Campus), unless otherwise noted. The seminar is organized by the NT&RT Group at Zhejiang University.

Here are the past talks.

Click on a title to reveal its abstract.

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Schedule (2026–27 Fall)

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Sep 9

• Speaker: Jack Sempliner (University of California, Los Angeles)
• Title: On a cohomological Jacquet–Langlands correspondence for Shimura varieties
• We will discuss a new result on the p-adic geometry of Igusa stacks, which allows one to relate the p-adic geometry of Shimura varieties for a pair of groups G, G' which are global extended pure inner forms. Using this geometric input and the spectral action of Fargues–Scholze, we will discuss how this input may be used to prove the existence of Hecke-equivariant cohomological "Jacquet–Langlands" maps between the cohomology (even with integral or torsion coefficients) of the two Shimura varieties of abelian type associated to G, G'.

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Sep 16 (Two talks!)

• Speaker: Fernando Trejos (Princeton University)
• Title: (15:00–16:00) An Euler system for the triple product
• We discuss the construction of an Euler system for the "triple product:" the 8-dimensional p-adic Galois representation V = V_1 x V_2 x V_3, where V_i for i=1,2,3 is the representation attached to an ordinary cuspidal eigenform f_i of weight k_i (varying in a Hida family). Our construction is via the pullback method recently introduced by Sangiovanni Vincentelli and Skinner. The image of the Euler system under a Perrin-Riou regulator map is the p-adic L-function of Hsieh and Yamana that interpolates critical values of L(f_1 x f_2 x f_3 x \chi, s), where \chi is a Dirichlet character and the weights (k_1, k_2, k_3) are in the balanced range. The cyclotomic variable \chi is not seen by previous constructions, such as the diagonal cycles of Darmon and Rotger.

• Speaker: Amina Abdurrahman (ETH Zürich)
• Title: (16:15–17:15) A cohomological formula for the central value of symplectic L-functions and Reidemeister torsion
• I give a global cohomological formula for the central value of the L-function of a symplectic representation on a curve up to squares. It involves a map C. Soule defined in his work on the Lichtenbaum conjectures. The proof relies crucially on a similar formula for the Reidemeister torsion of 3-manifolds. I sketch both analogous arithmetic and topological pictures. This is based on joint work with A. Venkatesh. I will also give an arithmetic application, giving a topological perspective on the order of the Tate–Shafarevich group up to squares.

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Sep 23

• Speaker: Naoki Imai 今井直毅 (University of Tokyo 東京大学)
• Title: Toward finite-local compatibility in the Langlands program
• A finite field analogue of the Langlands correspondence was recently formulated in joint work with David Vogan. In this talk, we will discuss its construction and conjectural relationship with the categorical local Langlands correspondence.

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Oct 14

• Speaker: Huajie Li 李华杰 (Tsinghua University 清华大学)
• Title: TBD

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Oct 21

• Speaker: Zhongyipan Lin 林中一攀 (Tongji University 同济大学)
• Title: TBD

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Oct 28

• Speaker: Xenia Dimitrakopoulou (Aix-Marseille Université)
• Title: TBD

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Nov 11

• Speaker: Lucas Gerth (Centre National de la Recherche Scientifique)
• Title: TBD

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Nov 18

• Speaker: Andrew Graham (University of Oxford)
• Title: TBD

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Nov 25

• Speaker: Wen-Wei Li 李文威 (Peking University 北京大学)
• Title: TBD

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Dec 2

• Speaker: Arnaud Vanhaecke (Chinese Academy of Sciences 中国科学院)
• Title: TBD

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Dec 16 (Two talks!)

• Speaker: Volker Heiermann (Aix-Marseille Université)
• Title: TBD

• Speaker: Yujiao Jiang 蒋玉蛟 (Shandong University 山东大学)
• Title: TBD

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Dec 23

• Speaker: Ruishen Zhao 赵瑞屾 (Tsinghua University 清华大学)
• Title: TBD

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Dec 30

• Speaker: TBD (TBD)
• Title: TBD

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Jan 6

• Speaker: Rafael von Känel (Tsinghua University 清华大学)
• Title: TBD

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