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arXiv · 0803.1278

Nevanlinna-Pick interpolation for $C+BH^\infty$

Mrinal Raghupathi
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Abstract

Given an inner function $B$ we classify the invariant subspaces of the algebra $H^\infty_B:=\mathbb{C}+BH^\infty$. We derive a formula in terms of these invariant subspaces for the distance of an element in $L^\infty$ to a certain weak*-closed ideal in $H^\infty_B$ and use this to prove an analogue of the Nevanlinna-Pick interpolation theorem.

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Mrinal Raghupathi. 2008-09-21. Nevanlinna-Pick interpolation for $C+BH^\infty$. https://arxiv.org/abs/0803.1278

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