A quantum harmonic analysis approach to nonlinear time-frequency concentration

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Svela, Erling A. T., Trapasso, S. Ivan
Format: Preprint
Published: 2026
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866917543764033536
author Svela, Erling A. T.
Trapasso, S. Ivan
author_facet Svela, Erling A. T.
Trapasso, S. Ivan
contents We study nonlinear concentration problems for time-frequency distributions in the Cohen class. Using recent techniques from quantum harmonic analysis (QHA) we provide both positive and negative results, such as sufficient conditions for the existence of optimizers in terms of the ``window operator'' and explicit examples where the supremum is never attained. We also study the structural properties of window operators, in particular operators that yield weakly continuous concentration functionals and operators for which the nonlinear concentration problem admits an optimizer, also beyond the Heisenberg representation. We then consider generalizations to the study of concentration problems for phase space representations of operators. We consider generalized Husimi distributions via quantum convolution, and their optimization problem when optimizing over Hilbert--Schmidt and density operators. Lastly, we consider representations of operators on double phase space, in the spirit of quantum time-frequency analysis, and give a full solution in terms of the Weyl symbols.
format Preprint
id arxiv_https___arxiv_org_abs_2605_28786
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle A quantum harmonic analysis approach to nonlinear time-frequency concentration
Svela, Erling A. T.
Trapasso, S. Ivan
Functional Analysis
81S30, 42B10, 49Q10, 49R05, 94A12
We study nonlinear concentration problems for time-frequency distributions in the Cohen class. Using recent techniques from quantum harmonic analysis (QHA) we provide both positive and negative results, such as sufficient conditions for the existence of optimizers in terms of the ``window operator'' and explicit examples where the supremum is never attained. We also study the structural properties of window operators, in particular operators that yield weakly continuous concentration functionals and operators for which the nonlinear concentration problem admits an optimizer, also beyond the Heisenberg representation. We then consider generalizations to the study of concentration problems for phase space representations of operators. We consider generalized Husimi distributions via quantum convolution, and their optimization problem when optimizing over Hilbert--Schmidt and density operators. Lastly, we consider representations of operators on double phase space, in the spirit of quantum time-frequency analysis, and give a full solution in terms of the Weyl symbols.
title A quantum harmonic analysis approach to nonlinear time-frequency concentration
topic Functional Analysis
81S30, 42B10, 49Q10, 49R05, 94A12
url https://arxiv.org/abs/2605.28786