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Related papers: A note on the operator window of modulation spaces

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Projection operators arise naturally as one-particle density operators associated to Slater determinants in fields such as quantum mechanics and the study of determinantal processes. In the context of the semiclassical approximation of…

Mathematical Physics · Physics 2024-05-29 Laurent Lafleche

In this paper, we study a class of pseudo-differential operators known as time-frequency localization operators on $\mathbb Z^n$, which depend on a symbol $\varsigma$ and two windows functions $g_1$ and $g_2$. We define the short-time…

Functional Analysis · Mathematics 2023-08-22 Aparajita Dasgupta , Anirudha Poria

We introduce new classes of modulation spaces over phase space. By means of the Kohn-Nirenberg correspondence, these spaces induce norms on pseudo-differential operators that bound their operator norms on $L^p$-spaces, Sobolev spaces, and…

Functional Analysis · Mathematics 2015-04-23 Shahla Molahajloo , Götz E. Pfander

Given a matrix-weight $W$ in the Muckenhoupt class $\mathbf{A}_p(\mathbb{R}^n)$, $1\leq p<\infty$, we introduce corresponding vector-valued continuous and discrete $\alpha$-modulation spaces $M^{s,\alpha}_{p,q}(W)$ and…

Functional Analysis · Mathematics 2024-02-27 Morten Nielsen

In this paper we introduce and study some Hilbert-type operators acting from the function spaces into the sequence spaces. We give some sufficient and necessary conditions for the boundedness and compactness of these Hilbert-type operators.…

Functional Analysis · Mathematics 2023-12-27 Jianjun Jin

We study approximate Birkhoff-James orthogonality of bounded linear operators defined between normed linear spaces $\mathbb{X}$ and $\mathbb{Y}.$ As an application of the results obtained, we characterize smoothness of a bounded linear…

Functional Analysis · Mathematics 2024-08-13 Arpita Mal , Kallol Paul , T. S. S. R. K. Rao , Debmalya Sain

This note aims to present novel positive linear operators involving the Wright function. Furthermore, the present research established the moments of these newly defined operators and estimated the convergence rate using the classical…

Functional Analysis · Mathematics 2025-10-07 Prashantkumar Patel

In this paper we introduce Schwartz operators as a non-commutative analog of Schwartz functions and provide a detailed discussion of their properties. We equip them in particular with a number of different (but equivalent) families of…

Mathematical Physics · Physics 2016-05-25 Michael Keyl , Jukka Kiukas , Reinhard F. Werner

We obtain Gabor frame characterisations of modulation spaces defined via a class of translation-modulation invariant Banach spaces of distributions that was recently introduced in $[10]$. We show that these spaces admit an atomic…

Functional Analysis · Mathematics 2021-02-08 Andreas Debrouwere , Bojan Prangoski

This paper is one of a series of papers on coherent spaces and their applications, defined in the recent book 'Coherent Quantum Mechanics' by the first author. The paper studies coherent quantization -- the way operators in the quantum…

Mathematical Physics · Physics 2022-02-08 Arnold Neumaier , Arash Ghaani Farashahi

We introduce a notion of completely bounded holomorphic functions defined on the open unit ball of an operator space. We endow the set of these functions with an operator space structure, and in the scalar-valued case we identify an…

Functional Analysis · Mathematics 2024-05-16 Javier Alejandro Chávez-Domínguez , Verónica Dimant

In this note, we present a characterization of semistable unitary operators on $L^2(\mathbb{R})$, under the assumption that the operator is (i) translation-invariant, (ii) symmetric, and (iii) locally uniformly continuous (LUC) under…

Functional Analysis · Mathematics 2026-01-01 Xianghong Chen

We consider previously derived upper and lower bounds on the number of operators in a window of scaling dimensions $[\Delta - \delta,\Delta + \delta]$ at asymptotically large $\Delta$ in 2d unitary modular invariant CFTs. These bounds…

High Energy Physics - Theory · Physics 2020-06-17 Baur Mukhametzhanov , Sridip Pal

We give two weighted norm estimates for higher order commutator of classical operators such as singular integral and fractional type operators, between weighted $L^p$ and certain spaces that include Lipschitz, BMO and Morrey spaces. We also…

Analysis of PDEs · Mathematics 2020-09-29 Gladis Pradolini , Wilfredo Ramos , Jorgelina Recchi

This paper investigates advanced notions of lineability and spaceability within the frameworks of sequence spaces and operator ideals. We propose the notion of \emph{Standard Sequence Classes} to provide an environment that unifies numerous…

Functional Analysis · Mathematics 2026-02-12 Nacib G. Albuquerque , Jamilson R. Campos , Luiz Felipe P. Sousa

Phase spaces as given by the Wigner distribution function provide a natural description of infinite-dimensional quantum systems. They are an important tool in quantum optics and have been widely applied in the context of time-frequency…

Quantum Physics · Physics 2023-10-27 Bálint Koczor , Frederik vom Ende , Maurice de Gosson , Steffen J. Glaser , Robert Zeier

Fractional difference sequence spaces have been studied in the literature recently. In this work, some identities or estimates for the operator norms and the Hausdorff measures of noncompactness of certain operators on some difference…

Functional Analysis · Mathematics 2019-02-22 Faruk Özger

Recent work in Dynamical Sampling has been centered on characterizing frames obtained by the orbit of a vector under a bounded operator. We prove a necessary and sufficient condition for a pair of bounded commuting operators on a separable…

Functional Analysis · Mathematics 2025-07-10 Victor Bailey , Carlos Cabrelli

In this paper, the main aim is to consider the mapping properties of the maximal or nonlinear commutator for the fractional maximal operator with the symbols belong to the Lipschitz spaces on variable Lebesgue spaces in the context of…

Classical Analysis and ODEs · Mathematics 2023-10-24 W. Zhao , J. Wu

We consider a class of operator-induced norms, acting as finite-dimensional surrogates to the L2 norm, and study their approximation properties over Hilbert subspaces of L2 . The class includes, as a special case, the usual empirical norm…

Statistics Theory · Mathematics 2011-06-01 Arash A. Amini , Martin J. Wainwright
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