2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/122884These notes are based on my lectures at IMA summer program "Symmetries and Overdetermined Systems of Partial Differential Equations." Here I try to explain basic ideas of the ambient metric construction by studying the Szego kernel of the sphere.13 pagesComplex VariablesDifferential Geometry32A25; 53A30text