2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/63121We use a theorem of Tolman and Weitsman to find explicit formulæfor the rational cohomology rings of the symplectic reduction of flag varieties in C^n, or generic coadjoint orbits of SU(n), by (maximal) torus actions. We also calculate the cohomology ring of the moduli space of $n$ points in CP^k, which is isomorphic to the Grassmannian of k-planes in C^n, by realizing it as a degenerate coadjoint orbit.31 pages, 1 figureSymplectic GeometryAlgebraic GeometryCombinatorics53D20 (Primary), 14M15, 05E99 (Secondary)text