Showing math.FAShow all
3 papers · 1 filter
math.FA2025
Composition operators on weighted modulation spaces
Héctor Ariza, Carmen Fernández, Antonio Galbis
We study composition operators whose symbols are suitable perturbations of the identity and which act between different weighted modulation classes. We consider both modulation spa…
math.FA2024
Iterates of composition operators on global spaces of ultradifferentiable functions
Héctor Ariza, Carmen Fernández, Antonio Galbis
We analyze the behavior of the iterates of composition operators defined by polynomials acting on global classes of ultradifferentiable functions of Beurling type and being invaria…
math.FA2024
Detecting quasicrystals with quadratic time-frequency distributions
Paolo Boggiatto, Carmen Fernández, Antonio Galbis +1
The usefulness of time-frequency analysis methods in the study of quasicrystals was pointed out in a previous paper, where we proved that a tempered distribution on ${\mathbb…