Alexander Scott

Mathematical Institute, University of Oxford

"Graphs of large chromatic number?"

Let G be a graph with large chromatic number. What induced subgraphs must it contain? It may contain a large complete subgraph (or indeed just be a complete graph), but what can we say if this is not the case? We shall discuss some old questions and new results on this topic. (Joint work with Maria Chudnovksy and Paul Seymour.)