Oberseminar Algebraische und Komplexe Geometrie im WiSe25/26

Von Mitte Oktober bis Ende Januar findet das Oberseminar Donnerstags von 14 bis 16 Uhr (Thursdays from 2:15 to 3:45 pm) statt. Vorträge dauern etwa eine Stunde; Nach dem Vortrag ist Zeit für Fragen und zum informellen Austausch mit dem Gast geplant. Der Raum ist IA1/63.

• 16. Okt. 2025: Giacomo Nanni (Ruhr-Universität Bochum, Università di Bologna):  Lagrangian fibrations on Nikulin orbifolds.
  Abstract: The geometry of irreducible holomorphic symplectic (IHS, sometimes referred to as hyperkähler) manifolds can be studied through the numerical properties of algebraic classes with respect to a non-degenerate quadratic form on the second cohomology group. In this context, a famous conjecture (SYZ) predicts that the existence of Lagrangian fibrations is detected by the presence of certain isotropic classes. While the conjecture holds in all known examples, it remains open in general. Recently, singular analogues of IHS manifolds have been proposed, providing a new framework to test the conjecture in a singular setting. In this talk, I will focus on Nikulin orbifolds, which are among the simplest singular examples, and present recent work classifying possible fibrations in this deformation class, from which the SYZ conjecture follows in this specific case.
• 6. Nov. 2025: Ludvig Modin (Leibniz-Universität Hannover).
• 27. Nov. 2025: Fateme Sajadi (University of Toronto). Zoom talk.
• 4. Dez. 2025: Simon Brandhorst (Universität des Saarlandes).
• 15. Jan. 2025:Matei Toma (Université de Lorraine).