Christoffel functions on curves and domains

Totik, Vilmos

doi:10.1090/S0002-9947-09-05059-4

Christoffel functions on curves and domains
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Trans. Amer. Math. Soc. 362 (2010), 2053-2087 Request permission

Abstract:

Asymptotics for Christoffel functions are established for measures supported on unions of smooth Jordan curves and for area-like measures on unions of smooth Jordan domains. For example, in the former case $n$ times the $n$-th Christoffel function tends to the Radon-Nikodym derivative of the measure with respect to the equilibrium distribution of the support of the measure.

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