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Related papers: Continuous frames in Krein spaces

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We present a general approach to a modular frame theory in C*-algebras and Hilbert C*-modules. The investigations rely on the idea of geometric dilation to standard Hilbert C*-modules over unital C*-algebras that possess orthonormal Hilbert…

Operator Algebras · Mathematics 2025-05-08 Michael Frank , David R. Larson

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

Recent research has shown that the properties of overcomplete Gabor frames and frames arising from shift-invariant systems form a precise match with certain conditions that are necessary for a frame in $L^2(\mathbf R)$ to have a…

Functional Analysis · Mathematics 2017-05-02 Ole Christensen , Marzieh Hasannasab

Operator-valued frames (or g-frames) are generalizations of frames and fusion frames and have been used in packets encoding, quantum computing, theory of coherent states and more. In this paper, we give a new formula for operator-valued…

Functional Analysis · Mathematics 2015-04-27 L. Gavruta , P. Gavruta

In this paper, we introduce the concept of continuous $g-$atomic subspace for a bounded linear operator and gives several useful continuous resolution of the identity operator on a Hilbert space by implies the theory of continuous…

Functional Analysis · Mathematics 2024-09-10 Mohamed Rossafi , Fakhr-dine Nhari , Abdeslam Touri

The main purpose of our paper is a new approach to design of algorithms of Kaczmarz type in the framework of operators in Hilbert space. Our applications include a diverse list of optimization problems, new Karhunen-Lo\`eve transforms, and…

Functional Analysis · Mathematics 2021-04-27 Palle E. T. Jorgensen , Myung-Sin Song , James Tian

In this paper, our aim is to introduce the concept of a frame in n-Hilbert space and describe some of their properties. We further discuss tight frame relative to n-Hilbert space. At the end, we study the relationship between frame and…

Functional Analysis · Mathematics 2021-09-09 Prasenjit Ghosh , T. K. Samanta

We extend some results of M.G. Krein to the class of entire functions which can be represented as ratios of discrete Cauchy transforms in the plane. As an application we obtain new versions of de Branges' Ordering Theorem for nearly…

Complex Variables · Mathematics 2018-04-03 Evgeny Abakumov , Anton Baranov , Yurii Belov

A new notion in frame theory has been introduced recently under the name woven-weaving frames by Bemrose et. al. In the studying of frames, some operators like analysis, synthesis, Gram and frame operator play the central role. In this…

Functional Analysis · Mathematics 2018-08-16 Asghar Rahimi , Zahra Samadzadeh , Bayaz Daraby

In this paper, we introduce a new concept of K-biframes for Hilbert spaces. We then examine several characterizations with the assistance of a biframe operator. Moreover, we investigate their properties from the perspective of operator…

Functional Analysis · Mathematics 2024-02-15 Abdelilah Karara , Mohamed Rossafi

C*-categories are essentially norm-closed *-categories of bounded linear operators between Hilbert spaces. The purpose of this work is to identify suitable axioms defining Krein C*-categories, i.e. those categories that play the role of…

Operator Algebras · Mathematics 2011-12-30 Paolo Bertozzini , Kasemsun Rutamorn

We provide a rigorous analysis for the so-called endlessly continuable germs of holomorphic functions or in other words, the Ecalle's resurgent functions. We follow and complete an approach due to Pham, based on the notion of discrete…

Classical Analysis and ODEs · Mathematics 2015-03-27 Eric Delabaere , Yafei Ou

The universality properties of kernels characterize the class of functions that can be approximated in the associated reproducing kernel Hilbert space and are of fundamental importance in the theoretical underpinning of kernel methods in…

Machine Learning · Computer Science 2025-06-25 Franziskus Steinert , Salem Said , Cyrus Mostajeran

This paper presents an overview of close parallels that exist between the theory of positive operator-valued measures (POVMs) associated with a separable Hilbert space and the theory of frames on that space, including its most important…

Functional Analysis · Mathematics 2011-11-08 Bill Moran , Stephen Howard , Doug Cochran

In this paper we study hermitian kernels invariant under the action of a semigroup with involution. We characterize those hermitian kernels which realize the given action by bounded operators on a Krein space. Applications to the GNS…

Functional Analysis · Mathematics 2009-10-31 Tiberiu Constantinescu , Aurelian Gheondea

We answer a number of open problems in frame theory concerning the decomposition of frames into linearly independent and/or spanning sets. We prove that in finite dimensional Hilbert spaces, Parseval frames with norms bounded away from 1…

Functional Analysis · Mathematics 2010-04-15 Bernhard G. Bodmann , Peter G. Casazza , Vern I. Paulsen , Darrin Speegle

Motivated by the dynamical sampling problem, we study frames in an infinite dimensional Hilbert space generated by the iterates of a bounded operator T, also known as dynamical frames. We first characterize the operators that generate…

Functional Analysis · Mathematics 2025-11-19 A. Aguilera , C. Cabrelli , F. Negreira , V. Paternostro

We consider continuous structures which are obtained from finite dimensional Hilbert spaces over $\mathbb{C}$ by adding some unitary operators. Quantum automata and circuits are naturally interpretable in such structures. We consider…

Logic · Mathematics 2019-01-16 A. Ivanov

In this paper we establish a suprising fundamental identity for Parseval frames in a Hilbert space. Several variations of this result are given, including an extension to general frames. Finally, we discuss the derived results.

Functional Analysis · Mathematics 2007-05-23 R. Balan , P. G. Casazza , D. Edidin , G. Kutyniok

A $J$-frame is a frame $\mathcal{F}$ for a Krein space $(\mathcal{H}, [\, , \,])$ which is compatible with the indefinite inner product $[\, , \, ]$ in the sense that it induces an indefinite reconstruction formula that resembles those…