Homogeneous extremal function for a ball in ℝ²

• Autorzy: Mirosław Baran
• Języki publikacji: EN

Abstrakty

EN

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.

Słowa kluczowe

EN

homogeneous extremal function; Cauchy-Poisson transform

Kategorie tematyczne

• 41A17: Inequalities in approximation (Bernstein, Jackson, Nikol\cprime ski{\u\i}-type inequalities)

• Wydawca: Institute of Mathematics Polish Academy of Sciences
• Czasopismo: Annales Polonici Mathematici
• Rocznik: 1999
• Tom: 71
• Numer: 2
• Strony: 141-150

Daty

wydano

1999

otrzymano

1997-11-27

poprawiono

1998-10-09

Twórcy

autor

Mirosław Baran

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

Bibliografia

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