Monday 9 February 2026
15:00–16:30*

Paul Mücksch (Leibniz-Universität Hannover) — On the K(π,1)-problem for hyperplane arrangements

Understanding when complements of complex hyperplane arrangements are K(π,1)-spaces is a central problem linking topology, geometry, and combinatorics in arrangement theory. Over the decades, many remarkable results were obtained but still this property remains only partially understood, and notable conjectures persist. I will survey the current state with particular attention to unresolved problems, and I will present new connections among existing criteria as well as further developments concerning necessary and sufficient conditions.

* Eastern European Time, i.e. UTC+2 in winter and UTC+3 in summer.