Descriptive Dynamics

The purpose of the following informal lectures is to give a brief introduction to descriptive dynamics, which I understand here to be the descriptive theory of Polish group actions. I will concentrate on the foundations, and hopefully at a level accessible to anyone with a basic knowledge of descriptive set theory. I will illustrate some of the main methods used in this area, including Baire category arguments and various implementations of the "changing the topology" technique. A general reference for the results discussed in this paper is Becker-Kechris [1996]