Seminars in geometry/topology

The Topology Seminar Spring 2019 will be on Mondays 13:15 - 14:15 (or 14:00 - 15:00) in room 734, Sentralbygg 2.

Spring 2019 - Upcoming Talks

June 4 or 5, 13:15 - 14:15, room 734, Sentralbygg 2

Antoine Touzé (Université de Lille): TBA

Abstract: TBA

August 5, 13:15 - 14:15, room 734, Sentralbygg 2

Benjamin Collas (University of Bayreuth): TBA

Abstract: TBA

Spring 2019 - Previous Talks

February 25, 13:15 - 14:15, room 734, Sentralbygg 2

Jarl Gunnar Taxerås Flaten (NTNU): Programming with Category Theory

Abstract: Haskell is a programming language heavily inspired by category theory. We'll start by seeing how basic category theory is represented in this language, before having a deeper look at what monads are and their different uses here. Anyone with some familiarity with algebra is welcome—especially those who don't believe pure mathematics has real, practical uses!

March 4, 13:15 - 14:15, room 734, Sentralbygg 2

Viktoriya Ozornova (Ruhr-Universität Bochum): Homotopy theory for 2-categories

Abstract: Grothendieck and Quillen introduced a notion of homotopy equivalences for categories using a by-now-standard tool called "nerve" of a category. This idea leads to various models of categories-up-to-homotopy. In a joint ongoing project with Martina Rovelli, we study variants of the Roberts-Street-nerve for 2-categories and notions of homotopy equivalences arising from this nerve, with an eye towards 2-categories-up-to-homotopy.

April 1, 13:15 - 14:15, room 734, Sentralbygg 2

Ambrus Pal (Imperial College London): An arithmetic Yau-Zaslow formula

Abstract: We prove an arithmetic refinement of the Yau–Zaslow formula by replacing the classical Euler characteristic in Beauville’s argument by a variant of Levine’s motivic Euler characteristic. We derive several similar formulas for other related invariants, including Saito’s determinant of cohomology, and a generalisation of a formula of Kharlamov and Rasdeaconu on counting real rational curves on real K3 surfaces. Joint work with Frank Neumann.

2019-04-10, Markus Szymik