collaborators

7 papers

math.CA2026

Optimal concentration in the Paley-Wiener space

Luís Daniel Abreu, Michael Speckbacher

Let be a bounded interval and let be the corresponding Paley--Wiener space. For a measurable set of finite measure, consider t…

math.SP2026

Spectral deviation of concentration operators on reproducing kernel Hilbert spaces

Felipe Marceca, José Luis Romero, Michael Speckbacher +1

We study the eigenvalue profile of concentration operators (multiplication by an indicator function followed by projection) acting on reproducing kernel Hilbert spaces. The spectra…

math.CA2026

Convergence of Hermite expansions in modulation spaces

Philippe Jaming, Michael Speckbacher

The aim of this paper is to give an elementary proof that Hermite expensions of a function in the modulation space converges to in when and…

math.FA2025

On quantum large sieve inequalities and operator recovery from incomplete information

Luís Daniel Abreu, Michael Speckbacher, Erling A. T. Svela

We obtain large sieve type inequalities for the Rayleigh quotient of the restriction of phase space representations of higher rank operators, via an operator analogue of the short-…

math.FA2025

Localized frames without inequalities

Peter Balazs, Lukas Köhldorfer, Michael Speckbacher

We consider countable families of vectors in a separable Hilbert space, which are mutually localized with respect to a fixed localized Riesz basis. We prove the equivalence of the…

math.FA2025

Localised frames for tensor product spaces

Dimitri Bytchenkoff, Michael Speckbacher, Peter Balazs

In this paper, we investigate whether the tensor product of two frames, each individually localised with respect to a spectral matrix algebra, is also localised with respect to a s…