activity
20202026
collaborators

5 papers

math.FA2026

Riesz sequences near the critical density

Marcin Bownik, Jordy Timo van Velthoven

We construct Riesz sequences whose Beurling density is arbitrary close to the critical density in the setting of reproducing kernel Hilbert spaces on metric measure spaces. In part…

math.CA2026

Wavelet orthonormal bases for nonexpansive dilations

Jordy Timo van Velthoven, Felix Voigtlaender

We construct wavelet orthonormal bases for nonexpansive dilations and integer translations that do not admit a wavelet set. In addition, these orthonormal bases do not satisfy the…

math.FA2024

On wavelet coorbit spaces associated to different dilation groups

Hartmut Führ, Jordy Timo van Velthoven, Felix Voigtlaender

This paper develops methods based on coarse geometry for the comparison of wavelet coorbit spaces defined by different dilation groups, with emphasis on establishing a unified appr…

math.FA2020

The density theorem for discrete series representations restricted to lattices

José Luis Romero, Jordy Timo van Velthoven

This article considers the relation between the spanning properties of lattice orbits of discrete series representations and the associated lattice co-volume. The focus is on the d…

math.FA2020

On dual molecules and convolution-dominated operators

José Luis Romero, Jordy Timo van Velthoven, Felix Voigtlaender

We show that sampling or interpolation formulas in reproducing kernel Hilbert spaces can be obtained by reproducing kernels whose dual systems form molecules, ensuring that the siz…