Perverse schobers for filtered categories IIOberseminar Darstellungstheorie

by Merlin Christ (Bonn)

Wednesday Dec 17, 2025, 10:00 AM → 12:00 PM Europe/Berlin

N0.007 (Mathezentrum)

Perverse schobers on marked surfaces are a class of sheaves of stable infinity-categories that can be packaged into a combinatorial formalism. The global sections of a perverse schober define a stable infinity-category. The goal of this lecture series is to explain parallels between the theory of (finite) highest weight categories, and more general stratified categories, and the study of the categories of global sections of perverse schobers on the disc.

The first talk will be a general introduction to the formalism of perverse schobers parametrized by graphs.
In the second talk, we will introduce induction functors for perverse schobers and how these give rise to categorical versions of Lefschetz thimbles, whose analogue in highest weight theory are the standard objects. Talk 2 is based on parts of https://arxiv.org/abs/2509.01689.
In the third talk, which will take place in January 2026, we will further explore the relationship with stratified categories and introduce an analogue of Ringel duality for perverse schobers.
The talks will be kept accessible to an audience without much higher categorical background, but familiarity with the theory of triangulated categories.