Results 171 to 180 of about 498,404 (212)

Properties of iteration of toeplitz operators with toeplitz preconditioners

BIT Numerical Mathematics, 1998
Toeplitz operators are preconditioned by approximations applied to the symbol (also known as generating function) of the operator. The preconditioned operator divides in two parts, a compact one and a perturbation. As a result, Krylov subspace methods exhibit superconvergence in initial iterations. Convergence estimates are given in terms of the symbol
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Analytic Continuation of Toeplitz Operators

The Journal of Geometric Analysis, 2014
Let \(f(z)=\sum_\nu f_\nu z^\nu\) be a holomorphic function on the unit ball \({\mathbb B}^n\) in \({\mathbb C}^n\). For \(\alpha\in{\mathbb R}\), \textit{R.-H. Zhao} and \textit{K. Zhu} [Mém. Soc. Math. Fr., Nouv. Sér. 115, 1--103 (2008; Zbl 1176.32001)] considered \(\|f\|_{\alpha,\#}^2:=\sum_\nu\frac{\nu!}{|\nu|!}\frac{|f_\nu|^2}{(|\nu|+1)^{\alpha+n}}
Bommier-Hato, H., Engliš, M. (Miroslav), Youssfi, E.-H.   +2 more
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When is a Function of a Toeplitz Operator Close to a Toeplitz Operator?

1989
In this paper we consider conditions under which the operator f(Tα) - T f·α belongs to the Schatten — von Heumann class Sp and in particular conditions when f(Tα) - T f·α is of trace class. Here Tα is a Toeplitz operator which is defined for bounded α on the Hardy class H2 by $$ {T_\varphi }f = {\mathbb{P}_ + }\varphi f $$ (1) , where P+ is ...
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Rank of Truncated Toeplitz Operators

Complex Analysis and Operator Theory, 2016
A Toeplitz operator \(T_\phi\) with symbol \(\phi\in L^\infty\) is a map between Hardy spaces \(H^2\ni f\mapsto P(\phi f)\in H^2\), where \(P\) is the orthogonal projection onto \(H^2\). Recall that \(T_{\overline{f}g}=T_{\overline{f}}T_g\) for \(f,g\in H^\infty\).
Gu, Caixing, Kang, Dong-O
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Toeplitz operators on l p

1990
Some questions for Toeplitz operators on H p have already been answered in the preceding chapters. In particular, we settled the Fredholm theory for the operators in algℒ (H N p ) T(C N × N +H N × N ∞ ). Also notice the localization result stated in Theorem 2.96. However, many questions still remain open and it is only a small number of them which will
Albrecht Böttcher, Bernd Silbermann
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Analytic Toeplitz and Composition Operators

Canadian Journal of Mathematics, 1972
This paper is a continuation of [1] where we began the study of intertwining analytic Toeplitz operators. Recall that X intertwines two operators A and B if XA = BX. Let H2 be the Hilbert space of analytic functions in the open unit disk D for which
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On Toeplitz Operators and Similarity

American Journal of Mathematics, 1978
Clark, Douglas N., Morrel, Judith H.
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Toeplitz Operators and Toeplitz C*-Algebras

1996
In this chapter we develop a structure theory for multi-variable Toeplitz operators, using the Toeplitz C*-algebra generated by these operators and its representation theory.
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On Skew Toeplitz Operators, I

1988
This paper is concerned with the study of the invertibility properties of a certain class of operators which we call “skew Toeplitz”. Besides being of mathematical interest, these operators appear quite frequently in engineering applications. Our results will also be seen to be closely related to the classical theory of Hankel and Toeplitz operators ...
H. Bercovici, C. Foias, A. Tannenbaum
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On Quasisimilarity for Analytic Toeplitz Operators

Canadian Mathematical Bulletin, 1988
AbstractLet f be a function in H∞. We show that if f is inner or if the commutant of the analytic Toeplitz operator Tf is equal to that of Tb for some finite Blaschke product b, then any analytic Toeplitz operator quasisimilar to Tf is unitarily equivalent to Tf.
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