AbstractTheory of quantum multiplication and Gromov-Witten invariants of a smoothprojective algebraic variety X deals with enumerative questions concerningcurves in X. A long time ago physicists E. Witten, R. Dijkgraaf, E. Verlinde, andH. Verlinde discovered a remarkable system of non-linear differential equations on the generating series for Gromov-Witten invariants. In particular, onecan calc...
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...