The talks last around 50-60 minutes.
Address:
Endenicher Allee 60.
53115 Bonn, Germany
Contact: representationtheorybonn@gmail.com
If you would like to be added to the mailing list, you can sign up under the following link: https://listen.uni-bonn.de/wws/info/quivers.and.algebras
13.05.2026 (Wednesday) at 18:00 in room 0.008: Ricardo Canesin (Université Paris Cité)
Title: Additive categorification of the monoidal Lambda-invariant
Abstract: The Lambda-invariant for quantum affine algebras was introduced by Kashiwara-Kim-Oh-Park as an important tool in their study of the monoidal categorification of cluster algebras. It yields a quantization of the associated cluster algebra, and it was recently shown to coincide with Peigen Cao’s tropical invariant.
In this talk, we interpret these invariants via the additive categorification of cluster algebras using Higgs categories in the sense of Yilin Wu. Whenever the relative Ginzburg algebra is proper, we show that the Higgs category admits a canonical quantum structure generalizing those of Geiss-Leclerc-Schröer and Grabowski-Pressland, and we provide a homological interpretation of the corresponding tropical invariant.
For certain finite-rank cluster algebras categorified by Kashiwara-Kim-Oh-Park, we show that the associated relative Ginzburg algebra is indeed proper, and that our additive Lambda-invariant agrees with their monoidal one.
This is joint work with Peigen Cao and Geoffrey Janssens.
28.05.2026: Emily Poelders (University of Bonn)
Title: TBA
23.07.2026: Yilin Wu (University of Luxembourg)
Title: TBA
16.04.2026: Fang Yang (MPIM Bonn)
Title: Degenerations in graded quiver varieties and derived categories of Dynkin quivers
Abstract: For any acyclic quiver, Keller–Scherotzke provided a stratifying functor from the category of finite-dimensional modules of the singular Nakajima category to the derived category of the quiver. Under this functor, a degeneration of strata of a graded quiver variety corresponds to a degeneration, in the sense of Jensen–Su–Zimmermann, in the derived category. In this article, for any Dynkin quiver, we further investigate Jensen–Su–Zimmermann’s partial order and show that any degeneration of objects in the derived category can be obtained in this way.
23.04.2026: Carolin Hartung (Universität Bonn)
Title: Projective Presentations over quasicompact algebras
Abstract: In a joint work with Christoph Geiss, Daniel Labardini-Fragoso and Jan Schröer we give a general formula for minimal projective presentations of finite-dimensional modules over quasicompact basic algebras. This result generalizes a description of minimal projective presentations for modules over Jacobian algebras proven by Weyman, Derksen and Zelevinsky. In particular, we are able to drop their finiteness assumptions and work over fields of arbitrary characteristics.
30.04.2026: Veronica Calvo Cortes (MPI MiS Leipzig)
Title: Dyck Paths, Configuration Spaces and Polytopes for Linear Nakayama Algebras
Abstract: We present a combinatorial model of configuration spaces and polytopes associated to linear Nakayama algebras. Such configuration spaces were recently introduced for more general algebras by Arkani-Hamed, Frost, Plamondon, Salvatori and Thomas. In our special setting, we provide elementary proofs and explicit combinatorial constructions. From a Dyck path we define three related objects: a finite-dimensional algebra, an affine algebraic variety, and a polytope. Moreover, our constructions are natural: each relation in the poset of Dyck paths gives a morphism between the corresponding objects.