Factorization and approximation problems for matrix functions

Peller, V.¹

¹ Department of Mathematics, Kansas State University, Manhattan, Kansas 66506

Journal of the American Mathematical Society, Tome 11 (1998) no. 4, pp. 751-770

Résumé

We study maximizing vectors of Hankel operators with matrix-valued symbols. This study leads to a solution of the so-called recovery problem for unitary-valued functions and to a new approach to Wiener–Hopf factorizations for functions in a function space $X$ satisfying natural conditions. Finally, we improve earlier results of Peller and Young on hereditary properties of the operator of superoptimal approximation by analytic matrix functions.

Détail

DOI : 10.1090/S0894-0347-98-00274-4

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