BEGIN:VCALENDAR VERSION:2.0 PRODID:researchseminars.org CALSCALE:GREGORIAN X-WR-CALNAME:researchseminars.org BEGIN:VEVENT SUMMARY:Daria Poliakova (University of Southern Denmark) DTSTART:20221208T151500Z DTEND:20221208T170000Z DTSTAMP:20260422T065936Z UID:CJCS/94 DESCRIPTION:Title: 2- Associahedra and the velocity fan\nby Daria Poliakova (University of S outhern Denmark) as part of Copenhagen-Jerusalem Combinatorics Seminar\n\n Lecture held in Aud. 9 HCØ (KU).\n\nAbstract\nAssociahedra are polytopes that encode homotopy associativity and allow for the definition of A-infin ity categories. There are numerous polytopal realizations of associahedra\ , my favourite being due to Loday.\n\nNate Bottman introduced a family of abstract polytopes called 2-associahedra\, that should stand behind the th eory of (A-infinity\,2)-categories. While an associahedron K(n) compactif ies the moduli space of configurations of n points on a line\, a 2-associ ahedron K(n_1\, ... \, n_k) compactifies the moduli space of configuration s of k lines\, with n_i points on the line number i. The combinatorics of this object is rather intricate\, and the question of finding a polytopal realization is difficult.\n\nIn my talk\, I will define 2-associahedra and tell about our recent construction of complete fans realizing these abstr act polytopes. We are currently working to prove that these fans are proje ctive. Some cases are settled\, so there will be 3D pictures.\n LOCATION:https://researchseminars.org/talk/CJCS/94/ END:VEVENT END:VCALENDAR