Results 61 to 70 of about 94 (89)

On Algebras Generated by a Partial Isometry

Complex Analysis and Operator Theory, 2019
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Shi, Luoyi, Zhu, Sen
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Semi-generalized Partial Isometries

Results in Mathematics, 2019
A bounded linear operator \(A\) on a complex Hilbert space \(\mathcal H\) is called a partial isometry if \(A\) preserves the norm of any vector in the orthogonal complement of its null space. It is well known that, if \(A\) is a partial isometry, then the range space of \(A\) is closed and that \(A\) is a contraction operator.
Garbouj, Zied, Skhiri, Haïkel
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On normal partial isometries

Georgian Mathematical Journal, 2023
Abstract Our aim in this paper is to determine when a partially isometric matrix is normal. However, we do not restrict ourselves to the finite-dimensional case and we describe when a partial isometry in ℬ
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Partial isometries and an invariant of C*-algebras

Acta Mathematica Sinica, English Series, 2011
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Yao, Hong Liang, Fang, Xiao Chun
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C * -subalgebras generated by partial isometries

Journal of Mathematical Physics, 2009
We prove a structure theorem for a finite set G of partial isometries in a fixed countably infinite dimensional complex Hilbert space H. Our result is stated in terms of the C*-algebra generated by G. The result is new even in the case of a single partial isometry which is not an isometry or a coisometry, and in this case, it extends the Wold ...
Cho, Ilwoo, Jorgensen, Palle
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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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(A, m)-partial isometries in semi-Hilbertian spaces

Linear and Multilinear Algebra, 2023
Adel Saddi, Fatma Mahmoudi
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On the monoid of partial isometries of a finite star graph

Communications in Algebra, 2023
Vitor Hugo Fernandes, Tania Paulista
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