activity
20242026
collaborators

5 papers

math.CA2026

Asymptotic safety regions for Gabor frames generated by Hermite functions

Markus Faulhuber, Irina Shafkulovska, Ilya Zlotnikov

The aim of this paper is to establish new regions in the frame sets of Hermite functions . A classical result of Gröchenig and Lyubarskii shows that the Gabor system $\mathcal…

math.FA2026

Periodic Non-uniqueness Sets for Shift-invariant Spaces and Parity-Based Obstructions to the Frame Property for Gabor Systems

Alexander Ulanovskii, Ilya Zlotnikov

The goal of this note is twofold. First, we provide explicit examples of periodic (though not necessarily lattice) sets that give rise to Gabor systems failing to form frames. Our…

math.FA2026

Extreme and exposed points of shift-invariant spaces generated by Gaussian kernel and hyperbolic secant

Markus Valås Hagen, Alexander Ulanovskii, Denis Zelent +1

We characterize the extreme and exposed points of the unit ball (with respect to the -norm) in the shift-invariant space generated by the Gaussian function, as well as in the…

math.CV2025

Contractive Hardy--Littlewood inequalities in the Dirichlet range

Ole Fredrik Brevig, Aleksei Kulikov, Kristian Seip +1

The class consists of those analytic functions in the unit disc such that \[\|f\|_{α,p}^p := |f(0)|^p+\int_0^1 \left(\frac{d}{dr} M_p^p(r,f)\right) (1-r^2)^{α-1} \,dr <…

math.FA2024

Stability of shifts, interpolation, and crystalline measures

Alexander Ulanovskii, Ilya Zlotnikov

Let be the quasi shift-invariant space generated by -shifts of a function , where is a separated set. F…