Results 11 to 20 of about 766 (271)
Split Partial Isometries [PDF]
Complex Analysis and Operator Theory, 2011 Let \(\mathcal H\) be a Hilbert space and \({\mathcal B}({\mathcal H})\) denote the space of bounded operators on \(\mathcal H\). For \(A \in {\mathcal B}({\mathcal H})\), let \(R(A)\) denote its range space and \(N(A)\) be its null space. \(T \in {\mathcal B}({\mathcal H})\) is called a partial isometry if \(T\) is an isometry between \(N(T)^{\perp}\)
Andruchow, Esteban +2 more
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A -partial isometries and generalized inverses [PDF]
Linear Algebra and its Applications, 2013 Let \(A\) be a positive operator in \(B(H)\). One may consider the semi-inner product \(\langle x,y\rangle_A:=\langle Ax, y\rangle\). An operator \(T\in B(H)\) is called \(A\)-adjointable if it is adjointable with respect to \(\langle \cdot,\cdot\rangle_A\). Clearly, an \(A\)-adjoint \(T^\#\) of \(T\) exists if and only if \(AT^\#=T^*A\). Similarly, by
Arias, Maria Laura, Mbekhta, Mostafa
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Partial Isometries and EP Elements in Banach Algebras [PDF]
Abstract and Applied Analysis, 2011 New characterizations of partial isometries and EP elements in Banach algebra are presented.
Dijana Mosić, Dragan S. Djordjević
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A combinatorial proof of the extension property for partial isometries [PDF]
Commentationes Mathematicae Universitatis Carolinae, 2019 We present a short and self-contained proof of the extension property for partial isometries of the class of all finite metric spaces.
Jan Hubicka +2 more
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Nontrivial isometries on sp(α) [PDF]
International Journal of Mathematics and Mathematical Sciences, 1982 sp(α) is a Banach space of sequences x with ‖x‖=(∑i=0∞|xi|p+α∑i=0∞|xi+1−xi|p)1/p.
Stephen L. Campbell
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On partial isometries in C*-algebras [PDF]
Studia Mathematica, 2011 Fil: Arias, Maria Laura. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Saavedra 15.
Arias, Maria Laura, Mbekhta, Mostafa
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On low-dimensional partial isometries
The Electronic Journal of Linear Algebra, 2023 Two statements concerning $n$-by-$n$ partial isometries are being considered: (i) these matrices are generic, if unitarily irreducible, and (ii) if nilpotent, their numerical ranges are circular disks. Both statements hold for $n\leq 4$ but fail starting with $n=5$.
Qixiao He +2 more
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All partial breakings in N=2 $$ \mathcal{N}=2 $$ supergravity with a single hypermultiplet [PDF]
Journal of High Energy Physics, 2018 We consider partial supersymmetry breaking in N=2 $$ \mathcal{N}=2 $$ supergravity coupled to a single vector and a single hypermultiplet. This breaking pattern is in principle possible if the quaternion-Kähler space of the hypermultiplet admits (at ...
Ignatios Antoniadis +3 more
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On the hyperreflexivity of power partial isometries
Linear Algebra and its Applications, 2012 Let \(\mathcal H\) be a complex separable Hilbert space. For \(A\in B({\mathcal H})\), denote by \({\mathcal W}(A)\) the smallest algebra containing \(A\) and closed in the weak operator topology. An operator \(A\in B({\mathcal H})\) is called a power partial isometry if \(A^{n}\) is a partial isometry for every positive integer \(n\).
Piwowarczyk, Kamila, Ptak, Marek
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Unitaries and Partial Isometries in a Real W ∗ -Algebra [PDF]
Proceedings of the American Mathematical Society, 1976 The group of unitaries in a real W ∗
Kenneth E. Ekman
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