The language of categories and functors is not only an indispensable tool in many areas of high-level mathematics, but is itself an incredibly interesting subject, worthy of study in its own right.

Based on notions developed in the 1940s by Mac Lane and Eilenberg, category theory (or "generalised abstract nonsense" as it is sometimes known) attempts to unify mathematics by describing similar structures through the subject in terms of "objects" and "arrows".

By abstracting in this way homomorphisms, continuous maps, bijections and everything but the kitchen sink are shown to be simply different manifestations of the same structure. Abstraction breeding generality breeding abstraction.

Come along on Thursday at 7.30 (MS03) as Jonathan Elliott takes us on a brief tour of the amazing world of natural transformations, colimits and adjoint functors, with lots of examples of how it all works. Then pub.