English

Projected Inner-Function Dynamics and Crystalline Measures of Meyer-Blaschke type

Classical Analysis and ODEs 2026-07-21 v1

Abstract

We generalize a construction of Yves Meyer of sparse crystalline measures arising from powers of a Blaschke factor. Starting from a recursion fn=θnf0f_n=\theta^n f_0 on the unit circle where θ\theta is an inner function, we project the Fourier coefficient array fn^(k)\widehat{f_n}(k) to the real line by placing its entries at the frequencies k+αnk+\alpha n. We identify the role of model spaces in this construction: in Meyer's one-factor Blaschke recursion, the requirement that the coefficient array fn^(k)\widehat{f_n}(k) vanish whenever kn<0kn<0 is equivalent to f0Kzbλf_0\in K_{zb_\lambda}, and for general inner functions the condition f0Kzθf_0\in K_{z\theta} yields a purely atomic Radon measure with locally finite support and polynomial growth on the Fourier side. We also show that, when f0f_0 is holomorphic in an annulus containing the unit circle, exponential Fourier decay is sufficient to obtain a purely atomic Radon measure of polynomial growth, though not necessarily locally finite support. For finite Blaschke products, the coefficient recursion gives an explicit annihilating exponential polynomial whose zero set controls the support and separation of the inverse Fourier transform. This yields Meyer-Blaschke-type crystalline measures and Poisson identities with sampling and finite-truncation consequences.

Cite

@article{arxiv.2607.19026,
  title  = {Projected Inner-Function Dynamics and Crystalline Measures of Meyer-Blaschke type},
  author = {Oleg Szehr and Rachid Zarouf},
  journal= {arXiv preprint arXiv:2607.19026},
  year   = {2026}
}
R2 v1 2026-07-22T20:50:43.982Z