Spherical Functions of Fundamental $K$-Types Associated with the $n$-Dimensional Sphere

Juan Alfredo Tirao ; Ignacio Nahuel Zurrián

Symmetry, integrability and geometry: methods and applications, Tome 10 (2014)

Résumé

In this paper, we describe the irreducible spherical functions of fundamental $K$-types associated with the pair $(G,K)=({\mathrm{SO}}(n+1),{\mathrm{SO}}(n))$ in terms of matrix hypergeometric functions. The output of this description is that the irreducible spherical functions of the same $K$-fundamental type are encoded in new examples of classical sequences of matrix-valued orthogonal polynomials, of size $2$ and $3$, with respect to a matrix-weight $W$ supported on $[0,1]$. Moreover, we show that $W$ has a second order symmetric hypergeometric operator $D$.

Détail

Keywords: matrix-valued spherical functions; matrix orthogonal polynomials; the matrix hypergeometric operator; $n$-dimensional sphere.

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