AbstractMany important posets (partially ordered sets) in combinatorics have algebriac interpretations. We will go over three families of examples: toric varieties, Schubert varieties and matroid Schubert varieties. We will discuss how to translate some of the combinatorical invariants into the geometric ones, and the application of intersection cohomology groups in solving combinatorical probl...
IntroductionThe classical theory of algebraic geometry connects geometric concepts with corresponding notions in commutative algebra. In the recent decades there was an interest in building a parallel theory based on associative (non-commutative) algebras. We will discuss the basic ideas of this developing theory mostly following Ginzburg's lectures as well as several more recent papers.The cla...