Book 4

This book is based on a graduate course given by the author at the University of Wisconsin. It presents an exposition of basic material from descriptive set theory (the general theory of Borel sets and projective sets), leading up to a new proof of Louveau s separation theorem for analytic sets. It assumes some background in mathematical logic and set theory, and will be of interest to reseachers and advanced students in these areas as well as in mathematical analysis.