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Related papers: Unbounded Toeplitz Operators with Rational Symbols

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The classical theory of Toeplitz operators in spaces of analytic functions deals usually with symbols that are bounded measurable functions on the domain in question. A further extension of the theory was made for symbols being unbounded…

Functional Analysis · Mathematics 2014-05-23 Grigori Rozenblum , Nikolai Vasilevski

In this paper a definition is given for an unbounded Toeplitz-like operator with rational symbol which has poles on the unit circle. It is shown that the operator is Fredholm if and only if the symbol has no zeroes on the unit circle, and a…

Functional Analysis · Mathematics 2020-02-21 G. J. Groenewald , S. ter Horst , J. Jaftha , A. C. M. Ran

In this paper we consider a class of unbounded Toeplitz operators with rational matrix symbols that have poles on the unit circle and employ state space realization techniques from linear systems theory, as used in our earlier analysis in…

Functional Analysis · Mathematics 2024-10-01 G. J. Groenewald , S. ter Horst , J. Jaftha , A. C. M. Ran

This paper concerns the analysis of an unbounded Toeplitz-like operator generated by a rational matrix function having poles on the unit circle T. It extends the analysis of such operators generated by scalar rational functions with poles…

Functional Analysis · Mathematics 2020-06-01 G. J. Groenewald , S. ter Horst , J. Jaftha , A. C. M. Ran

Some preliminaries and basic facts regarding unbounded Wiener-Hopf operators (WH) are provided. WH with rational symbols are studied in detail showing that they are densely defined closed and have finite dimensional kernels and deficiency…

Functional Analysis · Mathematics 2021-05-18 Domenico P. L. Castrigiano

This paper is a continuation of the work on unbounded Toeplitz-like operators $T_\Om$ with rational matrix symbol $\Om$ initiated in Groenewald et. al (Complex Anal. Oper. Theory 15, 1(2021)), where a Wiener-Hopf type factorization of $\Om$…

Functional Analysis · Mathematics 2023-09-27 G. J. Groenewald , S. ter Horst , J. Jaftha , A. C. M. Ran

We study Toeplitz operators on the Bargmann space, with Toeplitz symbols given by exponentials of complex quadratic forms. We show that the boundedness of the corresponding Weyl symbols is necessary for the boundedness of the operators,…

Functional Analysis · Mathematics 2023-03-06 Lewis Coburn , Michael Hitrik , Johannes Sjoestrand

We define and study Toeplitz operators in the space of Herglotz solutions of the Helmholtz equation in $R^d$. As the most traditional definition of Toeplitz operators via Bergman-type projection is not available here, we use an approach…

Functional Analysis · Mathematics 2016-05-24 Grigori Rozenblum , Nikolai Vasilevski

We study Toeplitz operators on the Bargmann space, with Toeplitz symbols that are exponentials of inhomogeneous quadratic polynomials. It is shown that the boundedness of such operators is implied by the boundedness of the corresponding…

Functional Analysis · Mathematics 2019-07-16 Lewis Coburn , Michael Hitrik , Johannes Sjoestrand , Francis White

Quantization and spectral properties of Toeplitz operators acting on spaces of pluriharmonic functions over bounded symmetric domains and $\mathbb C^n$ are discussed. Results are presented on the asymptotics \begin{align*} \|…

Functional Analysis · Mathematics 2019-01-10 Robert Fulsche

In the present article, we study the discrete spectrum of certain bounded Toeplitz operators with harmonic symbol on a Bergman space. Using the methods of classical perturbaton theory and recent results by Borichev-Golinskii-Kupin and…

Spectral Theory · Mathematics 2022-04-28 Leonid Golinskii , Stanislas Kupin , Juliette Leblond , Masimba Nemaire

In this paper we study the Fredholm properties of Toeplitz operators acting on weighted Bergman spaces $A^p_{\nu}(\mathbb{B}^n)$, where $p \in (1,\infty)$ and $\mathbb{B}^n \subset \mathbb{C}^n$ denotes the $n$-dimensional open unit ball.…

Functional Analysis · Mathematics 2018-04-12 Raffael Hagger

This paper studies matrix-valued truncated Toeplitz operators, which are a vectorial generalisation of truncated Toeplitz operators. It is demonstrated that, although there exist matrix-valued truncated Toeplitz operators without a matrix…

Functional Analysis · Mathematics 2022-01-26 Ryan O'Loughlin

While the symbol map for the collection of bounded Toeplitz operators is well studied, there has been little work on a symbol map for densely defined Toeplitz operators. In this work a family of candidate symbols, the Sarason Sub-Symbols,…

Functional Analysis · Mathematics 2014-12-19 Joel Rosenfeld

In this article, we determine the spectrum of real-analytic, non self-adjoint Toeplitz operators on compact K{\"a}hler manifolds and on the complex plane, on neighbourhoods of critical values of the symbol. We consider specifically critical…

Complex Variables · Mathematics 2026-03-17 Nathan Réguer

As a class of compact operators on the $\ell^2-$valued Bergman space $A^2_\alpha (\mathbb B_n, \ell^2)$ on the unit ball $\mathbb B_n,$ we study Toeplitz operators with $BMO^1_\alpha (\mathbb B_n, \mathcal L(\ell^2))$ operator-valued…

Classical Analysis and ODEs · Mathematics 2025-10-23 David Békollè , Hugues Olivier Défo , Edgar L. Tchoundja

Using the approach based on sesquilinear forms, we introduce Toeplitz operator in the analytic Bergman space on the upper half-plane with strongly singular symbols, derivatives of measures. Conditions for boundedness and compactness of such…

Functional Analysis · Mathematics 2019-12-12 Grigori Rozenblum , Nikolai Vasilevski

The theory of Toeplitz quantization presented in our previous paper is extended and further developed to include diverse and interesting non-commutative realizations of the classical Euclidean plane. This is done using Hilbert spaces of…

Quantum Physics · Physics 2021-05-19 Micho Durdevich , Stephen Bruce Sontz

Truncated Toeplitz operators are compressions of Toeplitz operators on model spaces; they have received much attention in the last years. This survey article presents several recent results, which relate boundedness, compactness, and…

Functional Analysis · Mathematics 2016-01-08 Isabelle Chalendar , Emmanuel Fricain , Dan Timotin

We consider kernels of unbounded Toeplitz operators in $H^p(\mathbb C^+)$ in terms of a factorization of their symbols. We study the existence of a minimal Toeplitz kernel containing a given function in $H^p(\mathbb C^+)$, we describe the…

Functional Analysis · Mathematics 2020-04-22 M. Cristina Câmara , M. Teresa Malheiro , Jonathan R. Partington
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