2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/162592A review of the uses of the CD kernel in the spectral theory of orthogonal polynomials, concentrating on recent results.To appear in "Perspectives in PDE, Harmonic Analysis and Applications" in honor of V.G. Maz'ya's 70th birthday, to be published in Proceedings of Symposia in Pure Mathematics (Dorina Mitrea and Marius Mitrea, editors)Spectral Theory34L40, 47-02, 42C05text