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Related papers: Integral Operator Frames on Hilbert C*-modules

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In this paper we establish the semi-Fredholm theory on Hilbert C*-modules as a continuation of Fredholm theory on Hilbert C*-modules established by Mishchenko and Fomenko. We give a definition of a semi-Fredholm operator on Hilbert…

Operator Algebras · Mathematics 2019-12-19 Stefan Ivkovic

In this paper, we give a multiplication operator representation of bounded self-adjoint operators T on a Hilbert space H such that -- is a frame for H, for some -- . We state a necessary condition in order for a frame -- to have a…

Functional Analysis · Mathematics 2023-01-18 Jahangir Cheshmavar , Ayyaneh Dallaki , Javad Baradaran

K-frames were recently introduced by L. G\v{a}vruta in Hilbert spaces to study atomic systems with respect to bounded linear operator. Also controlled frames have been recently introduced by P. Balazs in Hilbert spaces to improve the…

Functional Analysis · Mathematics 2016-02-15 Asghar Rahimi , Shahram Najafzadeh , Mohamad Nouri

In this paper, we obtain several extensions of semi-Fredholm theory on Hilbert modules by generalizing in this setting their classical counterparts regarding Weyl operators and Drazin invertible operators.

Operator Algebras · Mathematics 2023-02-14 Stefan Ivkovic

Multipliers have been recently introduced by P. Balazs as operators for Bessel sequences and frames in Hilbert spaces. These are operators that combine (frame-like) analysis, a multiplication with a fixed sequence (called the symbol) and…

Functional Analysis · Mathematics 2012-04-09 Asghar Rahimi , Abolhassan Fereydooni

In this paper we consider A-Fredholm and semi-A-Fredholm operators on Hilbert C*-modules over a W*-algebra A defined in [3],[10]. Using the assumption that A is a W*-algebra (and not an arbitrary C*-algebra), we obtain several results such…

Operator Algebras · Mathematics 2020-02-18 Stefan Ivkovic

In this paper, we obtain some new properties of weaving frames and present some conditions under which a family of frames is woven in Hilbert spaces. Some characterizations of weaving frames in terms of operators are given. We also give a…

Functional Analysis · Mathematics 2019-01-08 Dongwei Li

Frames for operators or k-frames were recently considered by Gavruta (2012) in connection with atomic systems. Also generalized frames are important frames in the Hilbert space of bounded linear operators. Fusion frames, which are a special…

Functional Analysis · Mathematics 2018-06-12 Vahid Sadri , Reza Ahmadi , Asghar Rahimi

Given a separable unital C*algebra $C$, let $E_n$ denote the Hilbert module equal to the completion of the Schwartz space of rapidly decreasing smooth functions from $R^n$ to $C$ equipped with the $C$-valued inner product given by…

Operator Algebras · Mathematics 2007-05-23 Severino T. Melo , Marcela I. Merklen

Frames play significant role in various areas of science and engineering. In this paper, we introduce the concepts of frames for $End_{\mathcal{A}}^{\ast}(\mathcal{H, K})$ and their generalizations. Moreover, we obtain some new results for…

Operator Algebras · Mathematics 2019-07-05 Mohamed Rossafi , Samir Kabbaj

Let $\{T_1, \ldots, T_n\}$ be a set of $n$ commuting bounded linear operators on a Hilbert space $\mathcal{H}$. Then the $n$-tuple $(T_1, \ldots, T_n)$ turns $\mathcal{H}$ into a module over $\mathbb{C}[z_1, \ldots, z_n]$ in the following…

Functional Analysis · Mathematics 2014-09-30 Jaydeb Sarkar

Controlled frames and g-frames were considered recently as generalizations of frames in Hilbert spaces. In this paper we generalize some of the known results in frame theory to controlled g-frames. We obtain some new properties of…

Functional Analysis · Mathematics 2019-12-19 Dongwei Li , Jinsong Leng

In this work, we provide some constructions and the sum of new continuous K-g-frames in Hilbert$C^{\ast}$-Modules. We provide certain necessary and sufficient conditions for some adjointable operators on $\mathcal{H}$, under which new…

Functional Analysis · Mathematics 2024-02-06 Abdelilah Karara , Mohamed Rossafi , Mohammed Klilou , Samir Kabbaj

In this paper, firstly we investigate conditions under which the action of an operator on a $K$-frame, remain again a $K$-frame for Hilbert module E. We also give a generalization of Douglas Theorem and we shall use it to prove the sum of…

Operator Algebras · Mathematics 2018-02-07 Gh. Abbaspour Tabadkan , A. A. Arefijamaal , M. Mahmoudieh

Controlled frames have been the subject of interest because of its ability to improve the numerical efficiency of iterative algorithms for inverting the frame operator. In this paper, we introduce the concepts of controlled g-fusion frame…

Operator Algebras · Mathematics 2021-12-10 Fakhr-dine Nhari , Mohamed Rossafi

Linear spaces with an Euclidean metric are ubiquitous in mathematics, arising both from quadratic forms and inner products. Operators on such spaces also occur naturally. In recent years, the study of multivariate operator theory has made…

Functional Analysis · Mathematics 2019-01-15 Gadadhar Misra

In this paper we intend to introduce the concept of c-K-g-frames, which are the generalization of K-g-frames. In addition, we prove some new results on c-K-g-frames on Hilbert spaces. Moreover, we define the related oprators of c-K-g…

Functional Analysis · Mathematics 2019-05-15 E. Alizadeh , M. H. Faroughi , M. Rahmani

One of the most important problems in the studying of frames and its extensions is the invariance of these systems under perturbation. The current paper is concerned with the invariance of Modular biframes for operators under some class of…

Functional Analysis · Mathematics 2024-04-26 Salah Eddine Oustani , Mohamed Rossafi

Woronowicz introduced the functional calculus for normal operators in Hilbert C*-modules. The aim of this paper is to translate, if possible, some basic properties of the functional calculus in Hilbert spaces to the Hilbert C*-module…

funct-an · Mathematics 2008-02-03 Johan Kustermans

We study adjointable, bounded operators on the direct sum of two copies of the standard Hilbert C*-module over a unital C*-algebra A that are given by upper triangular 2 by 2 operator matrices. Using the definition of A-Fredholm and…

Functional Analysis · Mathematics 2020-12-08 Stefan Ivkovic