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Extreme points in the isometric embedding problem for model spaces

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Abstract

In 1996 A. Aleksandrov solved the isometric embedding problem for the model spaces KΘ with an arbitrary inner function Θ.We find all extreme points of this convex set of measures in the case when & is a finite Blaschke product, and obtain some partial results for generic inner functions.

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Acknowledgments

I thank the referee for drawing my attention to the lurking property for inner functions and the references [5], [6], and A. Kheifets for the valuable remarks about minifunctions and the result of Adamjan-Arov-Krein.

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Authors and Affiliations

  1. B. Verkin Institute for Low Temperature Physics and Engineering, 47 Nauky ave., Kharkiv, 61103, Ukraine

    Leonid Golinskii

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  1. Leonid Golinskii
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Correspondence to Leonid Golinskii.

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Golinskii, L. Extreme points in the isometric embedding problem for model spaces. JAMA 141, 441–456 (2020). https://doi.org/10.1007/s11854-020-0105-8

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  • DOI: https://doi.org/10.1007/s11854-020-0105-8

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