A maximum principle for quotient norms in $H^ \infty$
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- by Eric Hayashi PDF
- Proc. Amer. Math. Soc. 99 (1987), 323-327 Request permission
Abstract:
Let $G$ be a closed subset of the open unit disk $D$ in the complex plane, and let $p$ denote a general polynomial of degree $n$ which has all of its roots in $G$. For a fixed $h$ in ${H^\infty },||h - p{H^\infty }|{|_{{H^\infty }/p{H^\infty }}}$ is maximized only if all the zeros of $p$ are on the boundary of $G$.References
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Additional Information
- © Copyright 1987 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 99 (1987), 323-327
- MSC: Primary 30E10; Secondary 30C15, 30D50
- DOI: https://doi.org/10.1090/S0002-9939-1987-0870794-3
- MathSciNet review: 870794