Homotopy group quotients of dg categories and skew group algebras - Merlin Christ (Univ of Bonn) скачать в хорошем качестве

Homotopy group quotients of dg categories and skew group algebras - Merlin Christ (Univ of Bonn)

This is a recorded version of the following talk from our "New Directions in Group Theory and Triangulated Categories" series. To receive updates about this series, or to suggest speakers (including yourself), please email me at rudradipbiswas@gmail.com. More details about this seminar series are here - https://sites.google.com/view/ndgttc/... ------------------------------------------------------------------------ 134th Meeting of "New Directions in Group Theory and Triangulated Categories" Date: January 22, 2026; Thursday Time: 4 pm UK Speaker: Merlin Christ (University of Bonn) Title: Homotopy group quotients of dg categories and skew group algebras. Abstract: Consider a group G acting on a ring R (or more generally a dg algebra) by automorphisms. A classical construction in the representation theory of algebras is called the skew group ring G*R. The underlying abelian group of G*R is given by the G-fold coproduct of R, and the multiplication is 'twisted' by the action of G. We prove that the skew group ring is Morita equivalent to the dg categorical homotopy group quotient of D^perf(R). The proof is based on an identification between G-actions and D^perf(R)^\amalg G-linear structures on D^perf(R). A special case of interest includes the dg orbit categories of Keller. Based on arxiv:2501.13666. ------------------------------------------------------------------------