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arXiv · 2608.28801

Complex Analysis in completeness, spectral and scattering problems

Alexei Poltoratski
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Abstract

These lectures are aimed at junior researchers seeking to enter the field of applications of complex analysis to harmonic analysis, Fourier analysis, spectral and scattering theory for differential operators and related fields. Starting with classical completeness problems posed by Bernstein, Beurling and Malliavin, Wiener, Kolmogorov and Krein, the course progresses to the solutions of the Gap and Type Problems, inverse spectral problems for Schr\"odinger operators and canonical Hamiltonian systems, and pointwise convergence of the non-linear Fourier transform. Each lecture is supplemented with exercises and references.

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Alexei Poltoratski. 2026-08-28. Complex Analysis in completeness, spectral and scattering problems. https://arxiv.org/abs/2608.28801

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