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Related papers: Toeplitz operators and pseudo-extensions

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We consider the third order operator with small 1-periodic coefficients on the real line. The spectrum of the operator is absolutely continuous and covers all real line. Under the minimal conditions on the coefficients we show that there…

Mathematical Physics · Physics 2011-05-19 Andrey Badanin , Evgeny Korotyaev

Let $T = (T_1, \ldots, T_n)$ be a commuting tuple of bounded linear operators on a Hilbert space $\mathcal{H}$. The multiplicity of $T$ is the cardinality of a minimal generating set with respect to $T$. In this paper, we establish an…

Functional Analysis · Mathematics 2023-06-22 Arup Chattopadhyay , Jaydeb Sarkar , Srijan Sarkar

In this paper we study the minimality of the commutant of an analytic Toeplitz operator $M_\varphi$, when $M_\varphi$ is defined on the Hardy space $H^2(\mathbb{D})$ and $\varphi\in H^\infty(\mathbb{D})$, denotes a bounded analytic function…

Functional Analysis · Mathematics 2025-03-24 María José González , Fernando León-Saavedra

We prove several results concerning the theory of Toeplitz algebras over $p$-Fock spaces using a correspondence theory of translation invariant symbol and operator spaces. The most notable results are: The full Toeplitz algebra is the norm…

Functional Analysis · Mathematics 2020-06-03 Robert Fulsche

In this note we show that if two Toeplitz operators on a Bergman space commute and the symbol of one of them is analytic and nonconstant, then the other one is also analytic.

Functional Analysis · Mathematics 2007-05-23 Sheldon Axler , Zeljko Cuckovic , N. V. Rao

One of the most important results in operator theory is And\^o's \cite{ando} generalization of dilation theory for a single contraction to a pair of commuting contractions acting on a Hilbert space. While there are two explicit…

Functional Analysis · Mathematics 2018-03-23 Haripada Sau

In this paper, we investigate the conditions under which the Toeplitz Composition operator on the Hardy space $\mathcal{H}^2$ becomes complex symmetric with respect to a certain conjugation. We also study various normality conditions for…

Functional Analysis · Mathematics 2019-12-10 Anuradha Gupta , Aastha Malhotra

In this paper we determine a sufficient condition for the quasinilpotency of a commutator of compact operators via block-tridiagonal matrix form associated with a compact operator. We also prove that every compact operator is unitarily…

Functional Analysis · Mathematics 2024-01-31 Sasmita Patnaik , Rahul Sethi

We provide an example of a zero-dimensional compact metric space $X$ and its closed subspace $A$ such that there is no continuous linear extension operator for the Lipschitz pseudometrics on $A$ to the Lipschitz pseudometrics on $X$. The…

General Topology · Mathematics 2007-05-23 Michael Zarichnyi

Motivated by the work of Nazarov and Shapiro on the unit disk, we study asymptotic Toeplitzness of composition operators on the Hardy space of the unit sphere in C^n. We extend some of their results but we also show that new phenomena…

Functional Analysis · Mathematics 2013-08-12 Zeljko Cuckovic , Trieu Le

We study the spectrum of the product of two Toeplitz operators. Assume that the symbols of these operators are continuous and real-valued and that one of them is non-negative. We prove that the spectrum of the product of finite section…

Functional Analysis · Mathematics 2007-12-11 Bernard Bercu , Jean-Francois Bony , Vincent Bruneau

Let $(X, T^{1,0}X)$ be a connected orientable compact CR manifold of dimension $2n+1$, $n \geq 1$ with non-degenerate Levi curvature. In this paper, we study the algebra of Toeplitz operators on $X$ and we establish star product for some…

Complex Variables · Mathematics 2021-10-29 Andrea Galasso , Chin-Yu Hsiao

We provide a simple recipe for obtaining all self-adjoint extensions, together with their resolvent, of the symmetric operator $S$ obtained by restricting the self-adjoint operator $A:\D(A)\subseteq\H\to\H$ to the dense, closed with respect…

Mathematical Physics · Physics 2008-03-28 Andrea Posilicano

The classical Weyl-von Neumann theorem states that for any self-adjoint operator $A$ in a separable Hilbert space $\mathfrak H$ there exists a (non-unique) Hilbert-Schmidt operator $C = C^*$ such that the perturbed operator $A+C$ has purely…

Mathematical Physics · Physics 2009-07-06 Mark M. Malamud , Hagen Neidhardt

We take a new look at dilation theory for nonself-adjoint operator algebras. Among the extremal (co)extensions of a representation, there is a special property of being fully extremal. This allows a refinement of some of the classical…

Operator Algebras · Mathematics 2011-09-02 Kenneth R. Davidson , Elias G. Katsoulis

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

A $7$-tuple of commuting bounded operators $\mathbf{T} = (T_1, \dots, T_7)$ defined on a Hilbert space $\mathcal{H}$ is said to be a \textit{$\Gamma_{E(3; 3; 1, 1, 1)}$-contraction} if $\Gamma_{E(3; 3; 1, 1, 1)}$ is a spectral set for…

Functional Analysis · Mathematics 2025-10-31 Dinesh Kumar Keshari , Avijit Pal , Bhaskar Paul

We study self-adjoint extensions of operators which are the product of the multiplication operator by an analytic function and the analytic continuation in a strip. We compute the deficiency indices of the product operator for a wide class…

Mathematical Physics · Physics 2015-08-27 Yoh Tanimoto

We present an example of a zero-dimensional compact metric space $X$ and its closed subspace $A$ such that there is no continuous linear extension operator for the Lipschitz pseudometrics on $A$ to the Lipschitz pseudometrics on $X$. The…

General Topology · Mathematics 2012-07-13 Dušan Repovš , Mykhailo Zarichnyi

In this paper we use the notion of operator-valued symbol in order to compute the index of Toeplitz operators on compact Lie groups. Our approach combines the Connes index theorem and the infinite-dimensional operator-valued symbolic…

Functional Analysis · Mathematics 2018-10-23 Duván Cardona