These notes are a guide for the course to be taught at the NCTS 2005 Summer School on Harmonic Analysis in Taiwan. They contain a description of results and sometimes short indications about the proofs. Moreover, each section contains a list of references. For an introduction to the subject it is better to go to the books mentioned in the bibliography at the end of the notes: each one of them i...

First we give a compact treatment of the Jacobi polynomials on a simplex in IR which exploits and emphasizes the symmetries that exist. This includes the various ways that they can be defined: via orthogonality conditions, as a hypergeometric series, as eigenfunctions of an elliptic pde, as eigenfunctions of a positive linear operator, and through conditions on the Bernstein–Bézier form. We the...