2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/162341In this paper, we consider the problem of building a conformal boundary, embedding a pseudo-Riamnnian manifold as an open subset of a bigger one. We get first results about conformal maximality. We also show that in dimension $\geq 3$, there are rigidity properties for the topological boundary of such a conformal embedding. We get results of the same kind about general Cartan geometries.Differential Geometry53A30; 53C50text