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Related papers: Continuous frames for unbounded operators

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Let $H$ be a real Hilbert space. In this short note, using some of the properties of bounded linear operators with closed range defined on $H$, certain bounds for a specific convex subset of the solution set of infinite linear…

Functional Analysis · Mathematics 2020-06-30 Projesh Nath Choudhury , M. Rajesh Kannan , K. C. Sivakumar

The purpose of the paper is to introduce and study a new class of operators on semi-Hilbertian spaces i.e.; spaces generated by positive semidefinite sesquilinear forms. Let H be a Hilbert space and let A be a positive bounded operator on H…

General Mathematics · Mathematics 2019-12-09 Samir Al Mohammady , Sid Ahmed Ould Beinane , Sid Ahmed O. Ahmed Mahmoud

Gleason's theorem asserts the equivalence of von Neumann's density operator formalism of quantum mechanics and frame functions, which are functions on the pure states that sum to 1 on any orthonormal basis of Hilbert space of dimension at…

Quantum Physics · Physics 2018-08-16 Jiri Lebl , Asif Shakeel , Nolan Wallach

It is often inevitable to introduce an indefinite-metric space in quantum field theory. There is a problem to determine the metric structure of a given representation space of field operators. We show the systematic method to determine such…

Operator Algebras · Mathematics 2007-05-23 Katsunori Kawamura

We introduce the notion of a generalized fusion frame in quaternionic Hilbert space. A characterization of generalized fusion frame in quaternionic Hilbert space with the help of frame operator is being discussed. Finally, we construct…

Functional Analysis · Mathematics 2024-04-08 Prasenjit Ghosh

In this note, we first introduce the notation of weaving cfusion frames in separable Hilbert spaces. After reviewing the conditions for maintaining the weaving c-fusion frames under the bounded linear operator and also, removing vectors…

Functional Analysis · Mathematics 2019-01-15 Vahid Sadri , Reza Ahmadi , Gholamreza Rahimlou

Frame theory is an exciting, dynamic and fast paced subject with applications in numerous fields of mathematics and engineering. In this paper we study Continuous Frame and introduce Continuous Frame with $C^{\ast}$-valued bounds. Also, we…

Functional Analysis · Mathematics 2022-09-05 Mohamed Rossafi , M'hamed Ghiati , Mohammed Mouniane , Frej Chouchene , Samir Kabbaj

Given a LHS (Lattice of Hilbert spaces) $V_J$ and a symmetric operator $A$ in $V_J$, in the sense of partial inner product spaces, we define a generalized resolvent for $A$ and study the corresponding spectral properties. In particular, we…

Mathematical Physics · Physics 2016-10-24 Jean-Pierre Antoine , Camillo Trapani

A definition of frames for Krein spaces is proposed, which extends the notion of $J$-orthonormal basis of Krein spaces. A $J$-frame for a Krein space $(\HH, \K{\,}{\,})$ is in particular a frame for $\HH$ in the Hilbert space sense. But it…

Functional Analysis · Mathematics 2011-12-08 J. I. Giribet , A. Maestripieri , F. Martínez Pería , P. Massey

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

Logic · Mathematics 2014-06-19 Aleksander Ivanov

Using the unbounded picture of analytical K-homology, we associate a well-defined K-homology class to an unbounded symmetric operator satisfying certain mild technical conditions. We also establish an ``addition formula'' for the Dirac…

K-Theory and Homology · Mathematics 2007-05-23 Hela Bettaieb , Michel Matthey , Alain Valette

Frames in a separable quaternionic Hilbert space were introduced and studied in [17] to have more applications. In this paper, we extend the study of frames in quaternionic Hilbert spaces and introduce different types of duals of a frame in…

Functional Analysis · Mathematics 2018-03-16 S. K. Sharma , Ghanshyam Singh , Soniya Sahu

In this article, we propose a $p$-adic analogue of complex Hilbert space and consider generalizations of some well-known theorems from functional analysis and the basic study of operators on Hilbert spaces. We compute the $K$-theory of the…

Operator Algebras · Mathematics 2019-07-17 Anton Claußnitzer , Andreas Thom

Let H be an infinite-dimensional (real or complex) Hilbert space, viewed as a metric structure in its natural signature. We characterize the definable linear operators on H as exactly the "scalar plus compact" operators.

Logic · Mathematics 2010-10-13 Isaac Goldbring

Given a complex Hilbert space H, we study the differential geometry of the manifold A of normal algebraic elements in Z=L(H), the algebra of bounded linear operators on H. We represent A as a disjoint union of subsets M of Z and, using the…

Functional Analysis · Mathematics 2007-05-23 Jose M. Isidro

In this paper, we introduce and we study the concept of Continuous Controlled K-Frame for Hilbert $C^{\ast}$-Modules wich are generalizations of discrete Controlled K-Frames.

Functional Analysis · Mathematics 2021-10-06 Hamid Faraj , Samir Kabbaj , Hatim Labrigui , Abdeslam Touri , Mohamed Rossafi

Let $A$ be an operator on {a separable } Hilbert space $\cH$, and let $G \subset \cH$. It is known that - under appropriate conditions on $A$ and $G$ - the set of iterations $F_G(A)= \{A^j \gbf \; | \; \gbf \in G, \; 0 \leq j \leq L(\gbf)…

Functional Analysis · Mathematics 2016-12-02 Roza Aceska , Yeon Hyang Kim

The mechanism of describing quantum states by standard probability (tomographic one) instead of wave function or density matrix is elucidated. Quantum tomography is formulated in an abstract Hilbert space framework, by means of the identity…

Quantum Physics · Physics 2008-11-26 V. I. Man'ko , G. Marmo , A. Simoni , A. Stern , E. C. G. Sudarshan , F. Ventriglia

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

Given a stationary continuous-time process $f(t)$, the Hilbert-Schmidt operator $A_{\tau}$ can be defined for every finite $\tau$\cite{Vautard1989SingularSA}. Let $\lambda_{\tau,i}$ be the eigenvalues of $A_{\tau}$ with descending order. In…

Optimization and Control · Mathematics 2026-04-20 Yicun Zhen , Bertrand Chapron , Etienne Mémin