Seminário de Teoria Quântica do Campo Topológica  

13/07/2011, 14:00 — 15:00 — Sala P3.10, Pavilhão de Matemática
Stephen Huggett, University of Plymouth

Seifert graphs, Eulerian subgraphs, and partial duality

I will describe how to characterize the Seifert graphs of link diagrams, and how, using the notion of partial duality in ribbon graphs, this leads to a generalization of the classical result that a plane graph is Eulerian if and only if its geometric dual is bipartite. This is joint work with Iain Moffatt and Natalia Virdee.