Oberseminar Summer 2024

Die Vorträge finden jeweils donnerstags um 16:45 Uhr im Raum WSC-N-U-3.05 (im Mathematikgebäude ) statt. Directions from the train station.
Der Tee findet ab 16:15 statt.

Alle Interessenten sind herzlich eingeladen!

The seminar takes place on Thursday, starting at 4:45pm. The duration of each talk is about 60 minutes.
Everybody who’s interested is welcome to join.

11.4.2024 Yukako Kezuka (Paris) Non-vanishing results for some CM elliptic curves
18.4.2024 Irene Spelta (Barcelona) Special subvarieties of the Torelli locus: examples
25.4.2024 Alex Küronya (Frankfurt) tba
2.5.2024 N. N. tba
16.5.2024 Mihai Pavel (Bukarest) tba
23.5.2024 Stefano Marseglia (University of French Polynesia) tba
6.6.2024 reserviert
13.6.2024 Quentin Posva (Düsseldorf) tba
20.6.2024 (Guido Kings, tbc) tba
27.6.2024 Symposium Düsseldorf/Essen/Wuppertal
4.7.2024 Mario Kummer (TU Dresden) tba
11.7.2024 Alexander Petrov (IAS) tba
18.7.2024 Michael Thaddeus (Columbia) tba


Yukako Kezuka: Non-vanishing results for some CM elliptic curves

We prove non-vanishing results for the values at s=1 of the complex L-series of quadratic twists of the elliptic curves with complex multiplication introduced by B. Gross in his thesis. From this, we obtain the finiteness of their Tate–Shafarevich group. For a prime P lying above the prime 2, we also prove a P-converse theorem in the rank 0 case for the higher-dimensional abelian varieties obtained by restriction of scalars.

Irene Spelta: Special subvarieties of the Torelli locus: examples

The Torelli morphism j : Mg → Ag associates to an algebraic curve C its Jacobian JC (as a principally polarized abelian variety). Very classically, it is injective on geometric points. In this talk, we will discuss the interplay between the geometry of Mg and of Ag. In particular, we will consider certain special subvarieties. We will explain how this is linked to a conjecture by Coleman and Oort, and we will analyse explicit examples.