Humboldt University Berlin, Summer 2025
Time: Tuesdays 15:15 - 16:45
Venue: Room 3.006, Rudower Chaussee 25, 12489 Berlin
— See also the Algebraic Geometry Seminars at HU and FU —
NOTE: | This semester the seminar will take place from 15:15 - 16:45 !!! |
20.05.2025 | Marco Maculan (Jussieu, Paris) |
Title: | Affine vs. Stein in rigid geometry |
Abstract: | What is the relation between coherent cohomology on a complex variety and that of the associated analytic space? The natural map between them is certainly not surjective for cardinality reasons. It is not even injective in general: this is a consequence of the existence of a nonaffine algebraic variety which is Stein. In a joint work with J. Poineau, we show that over non-Archimedean field the situation is, pun intended, far more rigid. |
10.06.2025 | Abhishek Oswal (Freiburg) |
Title: | p-adic hyperbolicity of the moduli space of abelian varieties |
Abstract: | By a theorem of Borel, any holomorphic map from a complex algebraic variety to the moduli space of abelian varieties (and more generally to an arithmetic variety) is in fact algebraic. A key input is to prove that any holomorphic map from a product of punctured disks to such an arithmetic variety does not have any essential singularities. In this talk, I'll discuss a p-adic analogue of these results. This is joint work with Ananth Shankar and Xinwen Zhu (with an appendix by Anand Patel). |
THURSDAY 19.06.2025 | Philip Engel (Chicago, Illinois) |
Title: | Boundedness theorems for abelian fibrations |
Abstract: | I will report on forthcoming work, joint with Filipazzi, Greer, Mauri, and Svaldi, on boundedness results for abelian fibrations. We will discuss a proof that irreducible Calabi-Yau varieties admitting an abelian fibration are birationally bounded in a fixed dimension; and that Lagrangian fibrations of symplectic varieties, in a fixed dimension, are analytically bounded. Conditional on the generalized semiampleness/hyperkahler SYZ conjecture, this bounds the number of deformation classes of hyperkahler varieties in a fixed dimension, with second Betti number at least 5. |
24.06.2025 | Denis-Charles Cisinski (Regensburg) |
Title: | tba |
Abstract: | tba |