Factorization and approximation

problems for matrix functions

Author:
V. V. Peller

Journal:
J. Amer. Math. Soc. **11** (1998), 751-770

MSC (1991):
Primary 47B35, 30Dxx, 46Exx

DOI:
https://doi.org/10.1090/S0894-0347-98-00274-4

MathSciNet review:
1618768

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Abstract | References | Similar Articles | Additional Information

Abstract: 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 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.

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Additional Information

**V. V. Peller**

Affiliation:
Department of Mathematics, Kansas State University, Manhattan, Kansas 66506

Email:
peller@math.ksu.edu

DOI:
https://doi.org/10.1090/S0894-0347-98-00274-4

Received by editor(s):
June 11, 1997

Additional Notes:
The author is partially supported by NSF grant DMS 9304011.

Article copyright:
© Copyright 1998
American Mathematical Society