ICTP Mathematics Seminar - Thursday 20 February, at 14:30 - Georg Oberdieck - VENUE: E. Fermi Building, room 101

[ICTP Math Section]

*_ICTP MATHEMATICS SEMINARS 2025_
*

Thursday 20 Feb 2025, at 14:30

VENUE: ICTP - Enrico Fermi Building - Room 101


Speaker: Georg Oberdieck (University of Heidelberg)


Title: Orthogonal quasimodular forms, theta lifts and enumerative geometry


Abstract: I will give a basic introduction into recent work with B. 
Williams in which we define quasimodular forms for the orthogonal group 
and show how the notion interacts with the theta lift. In particular, we 
prove that the theta lift of a quasimodular produces a quasimodular if 
and only if a certain weight-depth inequality holds. In the last part of 
the talk we discuss how this relates to the Gromov-Witten theory of the 
Enriques surface and its limitation for more general K3 fibrations. No 
previous knowledge about modular forms is required (all notation can be 
reviewed).