Results 261 to 270 of about 1,411 (284)

Restrictions of Self-Adjoint Partial Isometries

Periodica Mathematica Hungarica, 1997
The aim of this short note is to provide a necessary and sufficient condition for a suboperator to have a selfadjoint partial isometry extension.
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Semigroups of Partial Isometries and Symmetric Operators

Integral Equations and Operator Theory, 2011
From the author's abstract: Let \(\{ V(t)\mid t \in [0 , \infty) \}\) be a one-parameter strongly continuous semigroup of contractions on a separable Hilbert space and let \(V(-t) : = V^{*}(t)\) for \(t \in [0, \infty)\). It is shown that, if \(V(t)\) is a partial isometry for all \(t \in [-t_0 , t_0]\), \(t_0 > 0\), then the pointwise two-sided ...
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Unitary extensions of partial isometries

Mathematische Nachrichten, 2011
Let \((A,B)\) be a pair of partial isometries with domains \(\mathcal D_A\), \(\mathcal D_B\) and ranges \(\mathcal R_A\), \(\mathcal R_B\), respectively, closed subspaces of a Hilbert space \(\mathcal H\). A commuting unitary extension of \((A,B)\) is a pair \((\widetilde{A},\widetilde{B})\) of commuting unitary operators \(\widetilde{A}\) and ...
Amoretti, Nieves, Domínguez, Marisela
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On a Generalization of Partial Isometries in Banach Spaces

gmj, 2008
Abstract This paper is concerned with the definition and study of semipartial isometries on Banach spaces. This class of operators, which is a natural generalization of partial isometries from Hilbert to general Banach spaces, contains in particular the class of partial isometries recently introduced by M. Mbekhta [Acta Sci.
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An optimal perturbation bound for the partial isometry associated to the generalized polar decomposition

Applied Mathematics and Computation, 2020
Chunhong Fu, Qingxiang Xu
exaly  

Some studies on partial isometry in rings with involution

Filomat, 2022
Wei Junchao, Junchao Wei
exaly  

Partial isometry and strongly EP elements

Filomat, 2021
Junchao Wei, Wei Junchao
exaly  

Partial isometries

1974
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Generalized multidimensional scaling: A framework for isometry-invariant partial surface matching

Proceedings of the National Academy of Sciences of the United States of America, 2006
Michael M Bronstein, Ron Kimmel, Bronstein Alexander M   +2 more
exaly  

Finding isometry groups in theory and practice

General Relativity and Gravitation, 1992
Dray Tevian
exaly