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arXiv · 1208.2704

The Takagi problem on the disk and bidisk

Jim Agler·Joseph A. Ball·John E. McCarthy
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Abstract

We give a new proof on the disk that a Pick problem can be solved by a rational function that is unimodular on the unit circle and for which the number of poles inside the disk is no more than the number of non-positive eigenvalues of the Pick matrix. We use this method to find rational solutions to Pick problems on the bidisk.

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Jim Agler, Joseph A. Ball, John E. McCarthy. 2012-08-13. The Takagi problem on the disk and bidisk. https://arxiv.org/abs/1208.2704

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