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Related papers: Unbounded Toeplitz Operators with Rational Symbols

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We study Toeplitz operators on the Bargmann space, whose Toeplitz symbols are exponentials of complex inhomogeneous quadratic polynomials. Extending a result by Coburn--Hitrik--Sj\"{o}strand, we show that the boundedness of such Toeplitz…

Functional Analysis · Mathematics 2023-05-31 Haoren Xiong

Let $\lambda$ be a complex number in the closed unit disc $\overline{\Bbb D}$, and $\cal H$ be a separable Hilbert space with the orthonormal basis, say, ${\cal E}=\{e_n:n=0,1,2,\cdots\}$. A bounded operator $T$ on $\cal H$ is called a {\em…

Functional Analysis · Mathematics 2013-12-11 Chih Hao Chen , Po Han Chen , Mark C. Ho , Meng Syun Syu

In a recent paper (Groenewald et al.\ {\em Complex Anal.\ Oper.\ Theory} \textbf{15:1} (2021)) we considered an unbounded Toeplitz-like operator $T_\Omega$ generated by a rational matrix function $\Omega$ that has poles on the unit circle…

Functional Analysis · Mathematics 2023-07-14 G. J. Groenewald , S. ter Horst , J. J. Jaftha , A. C. M. Ran

In this paper, we establish the essential criteria for the hyponormality and quasinormality of the unbounded Toeplitz operator $T_{\varphi}$ with non-harmonic symbol, acting on the Fock-Sobolev space $F^{2, m}(\mathbb{C})$. The study shows…

Functional Analysis · Mathematics 2025-12-02 Anuradha Gupta , Kajal Negi

We study the boundedness of Toeplitz-type operators defined in the context of the Calder\'on reproducing formula considering the specific wavelets whose Fourier transforms are related to Laguerre polynomials. Some sufficient conditions for…

Functional Analysis · Mathematics 2011-07-21 Ondrej Hutník

Asymmetric dual truncated Toeplitz operators acting between the orthogonal complements of two (eventually different) model spaces are introduced and studied. They are shown to be equivalent after extension to paired operators on…

Functional Analysis · Mathematics 2020-01-01 M. Cristina Câmara , Kamila Kliś-Garlicka , Bartosz Łanucha , Marek Ptak

Compressions of Toeplitz operators to coinvariant subspaces of $H^2$ are called truncated Toeplitz operators. We study two questions related to these operators. The first, raised by Sarason, is whether boundedness of the operator implies…

Functional Analysis · Mathematics 2009-11-14 A. Baranov , Isabelle Chalendar , Emmanuel Fricain , Javad Mashreghi , Dan Timotin

For $\mathbb{B}^n$ the $n$-dimensional unit ball and $D_n$ its Siegel unbounded realization, we consider Toeplitz operators acting on weighted Bergman spaces with symbols invariant under the actions of the maximal Abelian subgroups of…

Functional Analysis · Mathematics 2024-04-24 Raul Quiroga-Barranco , Armando Sanchez-Nungaray

The definition of Toeplitz operators in the Bergman space $A^2(D)$ of square integrable analytic functions in the unit disk in the complex plane is extended in such way that it covers many cases where the traditional definition does not…

Complex Variables · Mathematics 2016-05-24 Grigori Rozenblum , Nikolai Vasilevski

We relate dual-band general Toeplitz operators to block truncated Toeplitz operators and, via equivalence after extension, with Toeplitz operators with $4 \times 4$ matrix symbols. We discuss their norm, their kernel, Fredhomlness,…

Functional Analysis · Mathematics 2021-06-04 M. Cristina Câmara , Ryan O'Loughlin , Jonathan R. Partington

The geometric descriptions of the (essential) spectra of Toeplitz operators with piecewise continuous symbols are among the most beautiful results about Toeplitz operators on Hardy spaces $H^p$ with $1<p<\infty$. In the Hardy space $H^1$,…

Functional Analysis · Mathematics 2019-01-09 Santeri Miihkinen , Jani A. Virtanen

We study subnormal Toeplitz operators on the vector-valued Hardy space of the unit circle, along with an appropriate reformulation of P.R. Halmos's Problem 5: Which subnormal block Toeplitz operators are either normal or analytic? We extend…

Functional Analysis · Mathematics 2012-07-16 Raul Curto , In Sung Hwang , Woo Young Lee

We study Toeplitz operators on the Bargmann space, with Toeplitz symbols that are exponentials of complex quadratic forms, from the point of view of Fourier integral operators in the complex domain. Sufficient conditions are established for…

Functional Analysis · Mathematics 2023-03-23 Lewis Coburn , Michael Hitrik , Johannes Sjoestrand

Wiener-Hopf factorisation plays an important role in the theory of Toeplitz operators. We consider here Toeplitz operators in the Hardy spaces $H^p$ of the upper half-plane and we review how their Fredholm properties can be studied in terms…

Functional Analysis · Mathematics 2017-11-01 M. Cristina Câmara

Using the model theory for Toeplitz operators with smooth symbols developed by the fourth author in the 80's, we study whether such operators $T_{F}$ can be embedded into a $C_{0}$-semigroup of operators on the Hardy space $H^p$ of the open…

Functional Analysis · Mathematics 2026-01-08 Emmanuel Fricain , Sophie Grivaux , Maëva Ostermann , Dmitry Yakubovich

We characterise the boundedness of a Toeplitz operator on the Bergman space with an L^1 symbol.We also prove that the compactness of a Toeplitz operator on the Bergman space with an L^1 symbol is completely determined by the boundary…

Complex Variables · Mathematics 2012-11-14 Dieudonne Agbor

We study the determinants of Toeplitz matrices as the size of the matrices tends to infinity, in the particular case where the symbol has two jump discontinuities and tends to zero on an arc of the unit circle at a sufficiently fast rate.…

Mathematical Physics · Physics 2015-06-22 Christophe Charlier , Tom Claeys

The paper discusses the spectrum of Toeplitz operators in Bargmann spaces. Our Toeplitz operators have real symbols with a variable sign and a compact support. A class of examples is considered where the asymptotics of the eigenvalues of…

Spectral Theory · Mathematics 2009-12-23 Alexander Pushnitski , Grigori Rozenblum

Truncated Toeplitz operators and their asymmetric versions are studied in the context of the Hardy space $H^p$ of the half-plane for $1<p<\infty$. It is shown that they are equivalent after extension to $2 \times 2$ matricial Toeplitz…

Functional Analysis · Mathematics 2015-04-27 M. Cristina Câmara , Jonathan R. Partington

We study the boundedness of Toeplitz operators with locally integrable symbols on Bergman spaces $A^p(\Omega),$ $1<p<\infty,$ where $\Omega\subset \mathbb{C}$ is a bounded simply connected domain with polygonal boundary. We give sufficient…

Functional Analysis · Mathematics 2019-10-16 Paula Mannersalo