Conclusions
In the past few years a productive interchange of ideas has taken place between the engineering and operator theory communities. We have only emphasized the control theoretic side of this interchange, but actually it goes much further. In fact, similar techniques have already been used in circuit theory in the context of broadband matching, and indeed the first use of Nevanlinna-Pick in systems was precisely in this connection by Youla and Saito [12]. This work was greatly expanded by Helton, and we refer the interested reader to his paper [6] for a more complete picture of this direction in interpolation theory. The cooperation now going on between the two communities has already expressed itself in several joint conferences and a number of research papers coauthored by engineers and mathematicians. We are optimistic that the cross-fertilization between these fields will continue, to the benefit of both theoretical engineering and mathematics.
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Francis, B.A., Tannenbaum, A. Generalized interpolation in control theory. The Mathematical Intelligencer 10, 48–52 (1988). https://doi.org/10.1007/BF03023747
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DOI: https://doi.org/10.1007/BF03023747