abstract: (1) Elementary introduction to usual algebras of differential operators. We shall focus on the example of the projective line and see how this theory relates to the representation theory of sl(2).
(2) Algebras of chiral differential operators on the projective line and their relations to the affine sl(2).
(3) HIgher dimensional generalization: characteristic classes, flag manifolds, and affine Kac-Moody algebras.
Every effort will be made to make this course accessible and self-contained.