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Related papers: Wigner analysis of operators. Part III: Controllin…

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In this work, we extend Wigner's original framework to analyze linear operators by examining the relationship between their Wigner and Schwartz kernels. Our approach includes the introduction of (quasi-)algebras of Fourier integral…

Analysis of PDEs · Mathematics 2024-06-18 Elena Cordero , Gianluca Giacchi , Edoardo Pucci

We perform Wigner analysis of linear operators. Namely, the standard time-frequency representation \emph{Short-time Fourier Transform} (STFT) is replaced by the $\mathcal{A}$-\emph{Wigner distribution} defined by $W_{\mathcal A}…

Analysis of PDEs · Mathematics 2021-08-10 Elena Cordero , Luigi Rodino

We perform a Wigner analysis of Fourier integral operators (FIOs), whose main examples are Schr\"odinger propagators arising from quadratic Hamiltonians with bounded perturbations. The perturbation is given by a pseudodifferential operator…

Analysis of PDEs · Mathematics 2025-03-04 Elena Cordero , Gianluca Giacchi , Luigi Rodino

We study the phase-space concentration of the so-called generalized metaplectic operators whose main examples are Schr\"odinger equations with bounded perturbations. To reach this goal, we perform a so-called $\mathcal{A}$-Wigner analysis…

Analysis of PDEs · Mathematics 2022-09-15 Elena Cordero , Gianluca Giacchi , Luigi Rodino

We use time-frequency methods for the study of Fourier Integral operators (FIOs). In this paper we shall show that Gabor frames provide very efficient representations for a large class of FIOs. Indeed, similarly to the case of shearlets and…

Analysis of PDEs · Mathematics 2016-06-28 Elena Cordero , Fabio Nicola , Luigi Rodino

We construct, using simple geometrical arguments, a Wigner function defined on a discrete phase space of arbitrary integer Hilbert-space dimension that is free of redundancies. ``Ghost images'' plaguing other Wigner functions for discrete…

Quantum Physics · Physics 2009-11-11 Arturo Argüelles , Thomas Dittrich

We consider the Cauchy-problem for a class of scalar linear dispersive equations with rapidly oscillating initial data. The problem of high-frequency asymptotics of such models is reviewed,in particular we highlight the difficulties in…

Mathematical Physics · Physics 2007-05-23 Christof Sparber , Peter A. Markowich , Norbert J. Mauser

Within the expansive domain of optical sciences, achieving the precise characterization of light beams stands as a fundamental pursuit, pivotal for various applications, including telecommunications and imaging technologies. This study…

This work belongs to a series of articles which have been dedicated to the combination of signed particles and neural networks to speed up the time-dependent simulation of quantum systems. More specifically, the suggested networks are…

General Physics · Physics 2018-07-19 Jean Michel Sellier , Gaetan Marceau Caron , Jacob Leygonie

We introduce a general purpose algorithm for rapidly computing certain types of oscillatory integrals which frequently arise in problems connected to wave propagation and general hyperbolic equations. The problem is to evaluate numerically…

Numerical Analysis · Mathematics 2007-05-23 Emmanuel Candes , Laurent Demanet , Lexing Ying

We study the decay properties of Wigner kernels for Fourier integral operators of types I and II. The symbol spaces that allow a nice decay of these kernels are the Shubin classes $\Gamma^m(\mathbb{R^{2d}})$, with negative order $m$. The…

Functional Analysis · Mathematics 2024-02-06 Elena Cordero , Gianluca Giacchi , Luigi Rodino , Mario Valenzano

Higher (2nd)-order Wigner distribution function in quantum phase space for entangled bi-modal coherent states, a representative of higher (2nd)-order optical-polarization, is introduced by generalizing kernel (transiting) operator in…

Quantum Physics · Physics 2012-04-04 Ravi S. Singh , Sunil P. Singh , Lallan Yadava , Gyaneshwar K. Gupta

The Heisenberg evolution of a given unitary operator corresponds classically to a fixed canonical transformation that is viewed through a moving coordinate system. The operators that form the bases of the Weyl representation and its Fourier…

Quantum Physics · Physics 2007-05-23 A. M. Ozorio de Almeida , O. Brodier

This paper is concerned with the fast computation of Fourier integral operators of the general form $\int_{\R^d} e^{2\pi\i \Phi(x,k)} f(k) d k$, where $k$ is a frequency variable, $\Phi(x,k)$ is a phase function obeying a standard…

Numerical Analysis · Mathematics 2008-09-05 Emmanuel Candes , Laurent Demanet , Lexing Ying

We consider solving partial differential equations (PDEs) with Fourier neural operators (FNOs), which operate in the frequency domain. Since the laws of physics do not depend on the coordinate system used to describe them, it is desirable…

Machine Learning · Computer Science 2023-07-28 Jacob Helwig , Xuan Zhang , Cong Fu , Jerry Kurtin , Stephan Wojtowytsch , Shuiwang Ji

We use a noncommutative generalization of Fourier analysis to define a broad class of pseudo-probability representations, which includes the known bosonic and discrete Wigner functions. We characterize the groups of quantum unitary…

Mathematical Physics · Physics 2020-05-19 Sang Jun Park , Cedric Beny , Hun Hee Lee

In this work, we investigate the microlocal properties of the evolutions of Schr\"odinger equations using metaplectic Wigner distributions. So far, only restricted classes of metaplectic Wigner distributions, satisfying particular…

Analysis of PDEs · Mathematics 2026-02-10 Gianluca Giacchi , Davide Tramontana

Smoothed Wigner transforms have been used in signal processing, as a regularized version of the Wigner transform, and have been proposed as an alternative to it in the homogenization and / or semiclassical limits of wave equations. We…

Analysis of PDEs · Mathematics 2015-05-19 Agissilaos G. Athanassoulis , Norbert J. Mauser , Thierry Paul

The integral of the Wigner function of a quantum mechanical system over a region or its boundary in the classical phase plane, is called a quasiprobability integral. Unlike a true probability integral, its value may lie outside the interval…

Quantum Physics · Physics 2009-11-10 A. J. Bracken , D. Ellinas , J. G. Wood

Time-frequency localization operators, originally introduced by Daubechies (1988), provide a framework for localizing signals in the phase space and have become a central tool in time-frequency analysis. In this paper we introduce and study…

Functional Analysis · Mathematics 2025-11-04 Elena Cordero , Edoardo Pucci
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