(1) Departamento de Análisis Matemático, Universidad de Sevilla, Apdo (P. O. BOX) 1160, 41080 Sevilla, Spain
Abstract:
We introduce and study matrix Christoffel functions for a matrix
weight W.
We find an explicit expression of the matrix Christoffel functions
in terms of any sequence of orthonormal matrix polynomials with
respect to W. An extremal property related to the matrix moment
problem defined by W is established for the matrix Christoffel
functions. We finally find the relative asymptotic behavior of
the matrix Christoffel functions associated to matrix weights in
the matrix Nevai class.