Approximation and duality

This is joint work with R. Martinez Villa. Various types of approximations and a duality between subcategories can be used to establish a duality between “larger” categories. The lecture will provide a detailed case study where the duality is the Koszul duality between Koszul modules. This leads to a duality between the stabilized (as in stable homotopy theory, for example) category of modules and the derived category of tails. The classical particular case of the exterior and polynomial algebras is known as the BGG correspondence. All terms will be defined and explained.