This page hosts information on Patrick Da Silva's talk "What is ... Representation Theory?" at the "What is ...?" seminar. This talk will help you better understand the talk by Geordie Williamson.
This What Is seminar is meant to be a rough introduction to representation theory to be able to follow Geordie Williamson's talk. We will sketch the basic concepts : definition of a representation, Maschke's theorem, Schur's Lemma, character theory and if we have some time perhaps the link between representations and k[G]-modules. Since Geordie will mention modular representation theory I will give an example in characteristic p, where Maschke's theorem fails.