2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/77588Consider a compact Lie group and a closed subgroup. Generalizing a result of Klyachko, we give a necessary and sufficient criterion for a coadjoint orbit of the subgroup to be contained in the projection of a given coadjoint orbit of the ambient group. The criterion is couched in terms of the ``relative'' Schubert calculus of the flag varieties of the two groups.34 pages, 4 figures, revised and reorganizedSymplectic GeometryAlgebraic GeometryRepresentation Theorytext