Results 31 to 40 of about 5,926 (266)
Journal of Functional Analysis, 2003 A Banach space \(X\) is called \(\mathcal P\)-generated (where \(\mathcal P\) is a property of Banach spaces) if there is a Banach space \(Y\) with property \(\mathcal P\) and a continuous linear operator from \(Y\) into \(X\) with dense range. \textit{M. Fabian}, \textit{G. Godefroy} and \textit{V. Zizler} [Isr. J. Math.
Fabian, M. +3 more
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Convexity and the Euclidean Metric of Space-Time
Universe, 2017 We address the reasons why the “Wick-rotated”, positive-definite, space-time metric obeys the Pythagorean theorem. An answer is proposed based on the convexity and smoothness properties of the functional spaces purporting to provide the kinematic ...
Nikolaos Kalogeropoulos
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On a Generalization of the Hilbert Frame Generated by the Bilinear Mapping
Journal of Function Spaces, 2016 The concept of b-frame which is a generalization of the frame in Hilbert spaces generated by the bilinear mapping is considered. b-frame operator is defined; analogues of some well-known results of frame theory are obtained in Hilbert spaces.
Migdad Ismailov +2 more
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Testing the Dimension of Hilbert Spaces [PDF]
Physical Review Letters, 2008 Given a set of correlations originating from measurements on a quantum state of unknown Hilbert space dimension, what is the minimal dimension d necessary to describe such correlations? We introduce the concept of dimension witness to put lower bounds on d.
Brunner, N. +5 more
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Woven Frames in Quaternionic Hilbert Spaces
Journal of Mathematics, 2021 In this paper, we introduce and study woven frames in quaternionic Hilbert spaces. We also give some properties of woven frames and give some conditions on family of frames under which it is woven in quaternionic Hilbert spaces.
S. K. Sharma +2 more
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Some Remarks on Smooth Mappings of Hilbert and Banach Spaces and Their Local Convexity Property
AxiomsWe analyze smooth nonlinear mappings for Hilbert and Banach spaces that carry small balls to convex sets, provided that the radii of the balls are small enough.
Yarema A. Prykarpatskyy +3 more
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Nonpivot and Implicit Projected Dynamical Systems on Hilbert Spaces
Journal of Function Spaces and Applications, 2012 This paper presents a generalization of the concept and uses of projected dynamical systems to the case of nonpivot Hilbert spaces. These are Hilbert spaces in which the topological dual space is not identified with the base space.
Monica Gabriela Cojocaru, Stephane Pia
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International Journal of Adaptive Control and Signal Processing, EarlyView.This article proposes a convergent adaptive observer for a damped wave PDE and an infinite‐dimensional ODE coupled in cascade using sampled‐in‐space ODE state measurements. The proposed observer estimates the distributed states of the PDE and ODE along with unknown PDE parameters and spatial input.
Zehor Belkhatir +2 more
wiley +1 more source
Abstract and Applied Analysis, 2012 The concept of g-basis in Hilbert spaces is introduced, which generalizes Schauder basis in Hilbert spaces. Some results about g-bases are proved. In particular, we characterize the g-bases and g-orthonormal bases. And the dual g-bases are also discussed.
Xunxiang Guo
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Analysis of Subgradient Extragradient Iterative Schemes for Variational Inequalities
Journal of Mathematics, 2021 In this paper, we investigate the monotone variational inequality in Hilbert spaces. Based on Censor’s subgradient extragradient method, we propose two modified subgradient extragradient algorithms with self-adaptive and inertial techniques for finding ...
Danfeng Wu +3 more
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