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Nevanlinna-Pick interpolation: Pick matrices have bounded number of negative eigenvalues

Author(s): V. Bolotnikov; A. Kheifets; L. Rodman
Journal: Proc. Amer. Math. Soc. 132 (2004), 769-780.
MSC (2000): Primary 41A05, 32A35
Posted: July 29, 2003
MathSciNet review: 2019954
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Abstract: The Nevanlinna-Pick interpolation problem is studied in the class of functions defined on the unit disk without a discrete set, with the property that all their Pick matrices have not more than a prescribed number of negative eigenvalues. It is shown, in particular, that the degenerate problem always has a unique solution, not necessarily meromorphic. A related extension problem to a maximal function in the class is also studied.

References:

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