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Related papers: Metaplectic operators with quasi-diagonal kernels

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Nowhere dense classes of graphs are very general classes of uniformly sparse graphs with several seemingly unrelated characterisations. From an algorithmic perspective, a characterisation of these classes in terms of uniform quasi-wideness,…

Discrete Mathematics · Computer Science 2018-09-06 Stephan Kreutzer , Roman Rabinovich , Sebastian Siebertz

The aim of this paper is to get the boundedness of certain sublinear operators with rough kernel generated by Calder\'on-Zygmund operators on the generalized weighted Morrey spaces under generic size conditions which are satisfied by most…

Functional Analysis · Mathematics 2016-07-01 Ferit Gurbuz

Decay rates for the sequence of eigenvalues of positive and compact integral operators has been largely investigated for a long time in the literature. In this paper, the focus will be on positive integral operators acting on square…

Functional Analysis · Mathematics 2014-11-19 Thaís Jordão , Valdir A. Manegatto

We investigate the kernels of the transformation operators for one-dimensional Schroedinger operators with potentials, which are asymptotically close to Bohr almost periodic infinite-gap potentials.

Spectral Theory · Mathematics 2011-04-06 Katrin Grunert

A quasi-Hermitian operator is an operator that is similar to its adjoint in some sense, via a metric operator, i.e., a strictly positive self-adjoint operator. Whereas those metric operators are in general assumed to be bounded, we analyze…

Mathematical Physics · Physics 2014-09-12 Jean-Pierre Antoine , Camillo Trapani

We are consider domains in cotangent bundles with the property that the null foliation of their boundary is fibrating and the leaves satisfy a Bohr-Sommerfeld condition (for example, the unit disk bundle of a Zoll metric). Given such a…

Functional Analysis · Mathematics 2011-05-30 Gerardo Hernández-Dueñas , Alejandro Uribe

Consider a complex line bundle over a compact complex manifold equipped with an infinitely differentiable metric with strictly positive curvature form. Assign to positive tensor powers of this bundle the associated product metrics and…

Complex Variables · Mathematics 2013-08-27 Michael Christ

This paper studies the \(k^{th}-\)order slant Toeplitz and slant little Hankel operators on the weighted Bergman space \(\mathcal{A}_\alpha^2(\mathbb{D})\). These operators are constructed using a slant shift operator \(W_k\) composed with…

Functional Analysis · Mathematics 2025-07-10 Oinam Nilbir Singh , M. P. Singh , Thokchom Sonamani Singh

We study a spatial asymptotic behaviour at infinity of kernels $p_t(x)$ for convolution semigroups of nonlocal pseudo-differential operators. We give general and sharp sufficient conditions under which the limits $$ \lim_{r \to \infty}…

Analysis of PDEs · Mathematics 2017-06-01 Kamil Kaleta , Paweł Sztonyk

We study pseudodifferential equations and Riesz kernels attached to certain quadratic forms over p-adic fields. We attach to an elliptic quadratic form of dimension two or four a family of distributions depending on a complex parameter, the…

Functional Analysis · Mathematics 2014-06-20 O. Casas-Sanchez , W. A. Zuniga-Galindo

We prove a new off-diagonal asymptotic of the Bergman kernels associated to tensor powers of a positive line bundle on a compact K\"ahler manifold. We show that if the K\"ahler potential is real analytic, then the Bergman kernel accepts a…

Differential Geometry · Mathematics 2017-05-26 Hamid Hezari , Zhiqin Lu , Hang Xu

Let $M$ be a relatively compact connected open subset with smooth connected boundary of a complex manifold $M'$. Let $(L,h^L)\rightarrow M'$ be a positive line bundle over $M'$. Suppose that $M'$ admits a holomorphic $\mathbb{R}$-action…

Complex Variables · Mathematics 2023-12-27 Chin-Yu Hsiao , Xiaoshan Li , George Marinescu

It is well known that the matrix of a metaplectic operator with respect to phase-space shifts is concentrated along the graph of a linear symplectic map. We show that the algebra generated by metaplectic operators and by pseudodifferential…

Analysis of PDEs · Mathematics 2015-06-16 Elena Cordero , Karlheinz Gröchenig , Fabio Nicola , Luigi Rodino

The pseudospectra (or spectral instability) of non-selfadjoint operators is a topic of current interest in applied mathematics. In fact, for non-selfadjoint operators the resolvent could be very large outside the spectrum, making the…

Analysis of PDEs · Mathematics 2010-03-05 Nils Dencker

We review some classical and more recent results concerning kernels of Toeplitz operators and their relations with model spaces, which are themselves Toeplitz kernels of a special kind. We highlight the fundamental role played by the…

Functional Analysis · Mathematics 2017-11-28 M. Cristina Câmara , Jonathan R. Partington

A periodic linear graph operator acts on states (functions) defined on the vertices of a graph equipped with a free translation action. Fourier transform with respect to the translation group reveals the central spectral objects, Bloch and…

Spectral Theory · Mathematics 2025-02-10 Stephen P. Shipman , Frank Sottile

We use results and techniques from Werner's ``quantum harmonic analysis'' to show that $G$-invariant Toeplitz operators are norm dense in $G$-invariant Toeplitz algebras for all subgroups $G$ of the affine unitary group $U_n\ltimes…

Operator Algebras · Mathematics 2023-10-20 Vishwa Dewage , Mishko Mitkovski

We develop a stochastic approximation framework for learning nonlinear operators between infinite-dimensional spaces utilizing general Mercer operator-valued kernels. Our framework encompasses two key classes: (i) compact kernels, which…

Machine Learning · Statistics 2026-01-13 Jia-Qi Yang , Lei Shi

In this work we study the essential spectra of composition operators on weighted Bergman spaces of analytic functions which might be termed as "quasi-parabolic." This is the class of composition operators on $A_{\alpha}^{2}$ with symbols…

Functional Analysis · Mathematics 2018-03-01 Uğur Gül

We study operators on the Kalton-Peck Banach space $Z_2$ from various points of view: matrix representations, examples, spectral properties and operator ideals. For example, we prove that there are non-compact, strictly singular operators…

Functional Analysis · Mathematics 2022-07-05 Jesús M. F. Castillo , Manuel González , Raúl Pino