Homogeneous extremal function for a ball in ℝ²

Mirosław Baran

ArticleOriginal scientific text

Title

Homogeneous extremal function for a ball in ℝ²

Authors ¹

Affiliations

Institute of Mathematics Jagiellonian University Reymonta 4 30-059 Kraków, Poland

Abstract

We point out relations between Siciak's homogeneous extremal function

Ψ_{B}

and the Cauchy-Poisson transform in case

B

is a ball in ℝ². In particular, we find effective formulas for

Ψ_{B}

for an important class of balls. These formulas imply that, in general,

Ψ_{B}

is not a norm in ℂ².

Keywords

ENG

homogeneous extremal function, Cauchy-Poisson transform

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Title

Homogeneous extremal function for a ball in ℝ²

Affiliations

Abstract

Keywords

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