Best approximation by subharmonic functions

Wilson, J. M.; Zwick, D.

doi:10.1090/S0002-9939-1992-1092929-4

Best approximation by subharmonic functions
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by J. M. Wilson and D. Zwick PDF

Proc. Amer. Math. Soc. 114 (1992), 897-903 Request permission

Abstract:

Let $\Omega \subset {\mathbb {R}^d}$ be a bounded domain. We prove existence of best subharmonic approximations in ${L_\infty }(\Omega )$ and, for functions continuous in $\overline \Omega$, we characterize best continuous subharmonic approximations.

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