Abstract
Since the works of Schoen and Yau in the late 70's, it became clear that the existence of a minimizing area surface might to exert great influence on the geometry of a Riemannian 3-manifold. Along the last few years, researchers as M.Cai, G.J.Galloway, H.Bray, S.Brendle, F.C.Marques and A.Neves have proved several rigidity results which made use of the existence of such minimizing surfa…