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Related papers: Riesz bases in quaternionic Hilbert spaces

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In this paper, continuous piecewise quadratic finite element wavelets are constructed on general polygons in $\mathbb{R}^2$. The wavelets are stable in $H^s$ for $|s|<\frac{3}{2}$ and have two vanishing moments. Each wavelet is a linear…

Numerical Analysis · Mathematics 2018-01-04 Nikolaos Rekatsinas , Rob Stevenson

The existence of a Fourier basis with frequencies in $\mathbb{R}^d$ for the space of square integrable functions supported on a given parallelepiped in $\mathbb{R}^d$, has been well understood since the 1950s. In a companion paper, we…

Classical Analysis and ODEs · Mathematics 2024-03-14 Dae Gwan Lee , Goetz E. Pfander , David Walnut

The main objective of this article is to introduce Euler-Riesz difference sequence spaces of fractional order ${\tau} $ along with infinite matrices. Some topological properties of these spaces are considered here along with the Schauder…

Functional Analysis · Mathematics 2023-01-18 D. Jena , S. Dutta

This paper continues the study of infinite dimensional bicomplex Hilbert spaces introduced in previous articles on the topic. Besides obtaining a Best Approximation Theorem, the main purpose of this paper is to obtain a bicomplex analogue…

Functional Analysis · Mathematics 2013-02-06 K. S. Charak , R. Kumar , D. Rochon

We prove the existence of Riesz bases of exponentials of L^2(Omega), provided that Omega in R^d is a measurable set of finite and positive measure, not necessarily bounded, that satisfies a multi-tiling condition and an arithmetic property…

Classical Analysis and ODEs · Mathematics 2017-10-12 Carlos Cabrelli , Diana Carbajal

We construct a sequence ${\phi_i(\cdot-j)\mid j\in{\ZZ}, i=1,...,r}$ which constitutes a $p$-frame for the weighted shift-invariant space [V^p_{\mu}(\Phi)=\Big{\sum\limits_{i=1}^r\sum\limits_{j\in{\mathbb{Z}}}c_i(j)\phi_i(\cdot-j) \Big|…

Functional Analysis · Mathematics 2012-08-23 Stevan Pilipovic , Suzana Simic

In a series of papers published in this Journal (J. Math. Phys.), a discussion was started on the significance of a new definition of projective representations in quaternionic Hilbert spaces. The present paper gives what we believe is a…

High Energy Physics - Theory · Physics 2009-10-30 Stephen L. Adler , G. G. Emch

We characterize the reproducing kernel Hilbert spaces whose elements are $p$-integrable functions in terms of the boundedness of the integral operator whose kernel is the reproducing kernel. Moreover, for $p=2$ we show that the spectral…

Functional Analysis · Mathematics 2007-05-23 Claudio Carmeli , Ernesto De Vito , Alessandro Toigo

In this paper, we define the concept of the bi g-frame and then show some properties of the bi g-frame

Functional Analysis · Mathematics 2024-08-27 Sayyed Mehrab Ramezani

In this note we discuss notions of convolutions generated by biorthogonal systems of elements of a Hilbert space. We develop the associated biorthogonal Fourier analysis and the theory of distributions, discuss properties of convolutions…

Functional Analysis · Mathematics 2017-12-21 Michael Ruzhansky , Niyaz Tokmagambetov

We consider three special and significant cases of the following problem. Let D be a (possibly unbounded) set of finite Lebesgue measure in R^d. Find conditions on D for which the standard exponential basis on the unit cube of R^d is a…

Functional Analysis · Mathematics 2019-08-15 Laura De Carli , Alberto Mizrahi , Alexander Tepper

Main goal of this paper is to generalize Hadamard's real part theorem and invariant forms of Borel-Carath\'eodory's theorem from complex analysis to solutions of the Riesz system in the three-dimensional Euclidean space in the framework of…

Complex Variables · Mathematics 2010-04-09 J. Morais , K. Guerlebeck

The paper studies finite extensions of Bessel sequences in infinite-dimensional Hilbert spaces. We provide a characterization of Bessel sequences that can be extended to frames by adding finitely many vectors. We also characterize frames…

Functional Analysis · Mathematics 2016-04-21 Damir Bakić , Tomislav Berić

For finding the numerical solution of operator equations in many applications a decomposition in subspaces is needed. Therefore, it is necessary to extend the known method of matrix representation to the utilization of fusion frames. In…

Functional Analysis · Mathematics 2020-07-14 Peter Balazs , Mitra Shamsabadi , Ali Akbar Arefijamaal , Chilles Gardon

It is not usual to characterize an operator valued series via completeness of multiplier spaces. In this study, by using a series of bounded linear operators, we introduce the space $M^\infty_{R}\big(\sum_k T_k\big)$ of Riesz summability…

Functional Analysis · Mathematics 2021-02-18 Mahmut Karakuş , Ramazan Kama

An order bounded functional on a Riesz space is a difference of Riesz homomorphisms if and only if the kernel of this functional is a Riesz subspace of the ambient Riesz space.

Functional Analysis · Mathematics 2011-05-31 S. Kutateladze

We give two new global and algorithmic constructions of the reproducing kernel Hilbert space associated to a positive definite kernel. We further present ageneral positive definite kernel setting using bilinear forms, and we provide new…

Functional Analysis · Mathematics 2020-11-20 Daniel Alpay , Palle Jorgensen

In this paper, we introduce orthonoramal and Riesz bases for g-fusion frames and will show that the weights have basic roles. Next, we prove an effective theorem between frames and g-fusion frames by using an operator. Finally,…

Functional Analysis · Mathematics 2018-06-12 Gholamreza Rahimlou , Vahid Sadri , Reza Ahmadi

The notation of generalized Bessel multipliers is obtained by a bounded operator on $\ell^2$ which is inserted between the analysis and synthesis operators. We show that various properties of generalized multipliers are closely related to…

Functional Analysis · Mathematics 2018-02-20 GH. Abbaspour Tabadkan , H. Hossein-nezhad , A. Rahimi

We study a capacity theory based on a definition of a Riesz potential in metric spaces with a doubling measure. In this general setting, we study the basic properties of the Riesz capacity, including monotonicity, countable subadditivity…

Functional Analysis · Mathematics 2015-10-30 Juho Nuutinen , Pilar Silvestre