2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/140290In this note we give a numerical criterion that expresses the condition that an abelian variety be simple in terms of an invariant that is closely related to the s-invariant of Ein-Cutkosky-Lazarsfeld. The criterion yields new examples where s-invariants are irrational. It may also be viewed as a statement about the geometry of the ample cone.Algebraic Geometry14K05; 14C20text