Diffusion-orthogonal polynomial systems of maximal weighted degree
The author proves that the boundary of a diffusion-orthogonal polynomial system in \(\mathbb R^d\) is always an algebraic hypersurface of degree less than or equal \(2d\). In dimension 2, when the degree is maximal (so, equals 4), the symbol of \(L\) is a cometric of constant curvature. The author presents a self-contained classification-free proof of this property, and its multidimensional generalisation.
scientific article; zbMATH DE number 6754501
scientific article