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Related papers: Normal Truncated Toeplitz Operators

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In this note we discuss an open problem whether a truncated Toeplitz operator on a model space can be hypercyclic. We compute point spectrum and eigenfunctions for a class of truncated Toeplitz operators with polynomial analytic and…

Functional Analysis · Mathematics 2023-01-05 Anton Baranov , Andrei Lishanskii

A major open problem in the Theory of Toeplitz operators on the analytic Bergman space over the unit disk is the characterization of the commutant of a given Toeplitz operator--that is, the set of all bounded Toeplitz operators that commute…

Functional Analysis · Mathematics 2025-03-19 Aissa Bouhali , Issam Louhichi , Abdel Rahman Yousef

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

In this paper we introduce the class of matrix valued asymmetric truncated Hankel operators. By using characterizations of matrix valued asymmetric truncated Toeplitz operators, we characterize matrix valued asymmetric truncated Hankel…

Functional Analysis · Mathematics 2023-09-07 Rewayat Khan , Ji Eun Lee

We discuss generalizations of the Szeg\H{o} Limit Theorem to truncated Toeplitz operators. In particular, we consider compressions of Toeplitz operators to an increasing sequence of finite dimensional model spaces. We present two theorems.…

Functional Analysis · Mathematics 2024-04-05 Nazar Miheisi , Ryan O'Loughlin

An elementary method is given for estimates of the norms of the Toeplitz operators, determined by rational inner functions

Complex Variables · Mathematics 2008-07-29 Peyo Stoilov

We consider the class of positive bounded and semi-continuous functions defined on the two dimensional torus If f belongs to this class, then f will be considered as the symbol of a Toeplitz operator truncated on a triangle parametrised by…

Functional Analysis · Mathematics 2013-02-26 Jean-Marc Rinkel , Abdellatif Seghier

We use Toeplitz operators to define a star-product on Poisson manifolds whose Poisson structure is induced by a symplectic Lie algebroid. The Toeplitz operators we consider are defined on groupoids whose algebroid can be endowed with a…

Symplectic Geometry · Mathematics 2026-04-14 Clément Cren , Jean-Marie Lescure , Omar Mohsen

In this article, we completely characterize absolutely norm attaining Hankel operators and absolutely minimum attaining Toeplitz operators. We also improve \cite[Theorem 2.1]{RGSSSTOE1}, by characterizing the absolutely norm attaining…

Functional Analysis · Mathematics 2022-09-14 G. Ramesh , Shanola S. Sequeira

We present two novel results about Hilbert space operators which are nilpotent of order two. First, we prove that such operators are indestructible complex symmetric operators, in the sense that tensoring them with any operator yields a…

Functional Analysis · Mathematics 2012-07-17 Stephan Ramon Garcia , Bob Lutz , Dan Timotin

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

In this paper, we study matrix representations of truncated Toeplitz operators with respect to orthonormal bases which are invariant under a canonical conjugation map. In particular, we determine necessary and sufficient conditions for when…

Functional Analysis · Mathematics 2023-02-27 Ryan O'Loughlin

Toeplitz operators are met in different fields of mathematics such as stochastic processes, signal theory, completeness problems, operator theory, etc. In applications, spectral and mapping properties are of particular interest. In this…

Complex Variables · Mathematics 2015-11-30 Andreas Hartmann , Mishko Mitkovski

We consider truncated Toeplitz operator on nearly invariant subspaces of the Hardy space $H^2$. Of some importance in this context is the boundary behavior of the functions in these spaces which we will discuss in some detail.

Complex Variables · Mathematics 2011-01-20 Andreas Hartmann , William T. Ross

Recently, M. Mitkovski gave a criterion for the basicity of a sequence of complex exponentials in terms of the invertibility properties of a certain naturally associated Toeplitz operator, in the spirit of the celebrated work of…

Functional Analysis · Mathematics 2018-06-15 Emmanuel Fricain , Rishika Rupam

Applying standard techniques from Toeplitz operator theory, we analyze the asymptotics of the Hilbert-Smith norms of the TQFT operators coming from isotopy classes of one dimensional oriented submanifolds on a closed oriented surface. We…

Quantum Algebra · Mathematics 2007-05-23 Jorgen Ellegaard Andersen

We prove a spatial Isomorphism between two spaces of matrix valued truncated Toeplitz operators.

Functional Analysis · Mathematics 2020-03-12 Rewayat Khan

Toeplitz matrices are characterized by their constant diagonals, have been extensively studied in various settings, including over real and complex numbers. However, their study over quaternions is quite sparse. In this paper, we…

Functional Analysis · Mathematics 2025-10-07 Muhammad Ahsan Khan , Sohail Khan

Unbounded (and bounded) Toeplitz operators (TO) with rational symbols are analysed in detail showing that they are densely defined closed and have finite dimensional kernels and deficiency spaces. The latter spaces as well as the domains,…

Functional Analysis · Mathematics 2021-10-22 Domenico P. L. Castrigiano

Our goal is to compare various results for Toeplitz $T$ and Hankel $H$ operators. We consider semibounded operators and find necessary and sufficient conditions for their quadratic forms to be closable. This property allows one to define…

Functional Analysis · Mathematics 2017-11-08 D. R. Yafaev