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arXiv · 1707.07880

Quantitative estimates of sampling constants in model spaces

Andreas Hartmann·Philippe Jaming·Karim Kellay
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Abstract

We establish quantitative estimates for sampling (dominating) sets in model spaces associated with meromorphic inner functions, i.e. those corresponding to de Branges spaces. Our results encompass the Logvinenko-Sereda-Panejah (LSP) Theorem including Kovrijkine's optimal sampling constants for Paley-Wiener spaces. It also extends Dyakonov's LSP theoremfor model spaces associated with bounded derivative inner functions. Considering meromorphic inner functions allows us tointroduce a new geometric density condition, in terms of which the sampling sets are completely characterized. This, incomparison to Volberg's characterization of sampling measures in terms of harmonic measure, enables us to obtain explicitestimates on the sampling constants. The methods combine Baranov-Bernstein inequalities, reverse Carleson measures andRemez inequalities .

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Andreas Hartmann, Philippe Jaming, Karim Kellay. 2017-07-25. Quantitative estimates of sampling constants in model spaces. https://arxiv.org/abs/1707.07880

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