Results 1 to 10 of about 270 (141)
Presentations for monoids of finite partial isometries [PDF]
Semigroup Forum, 2015 In this paper we give presentations for the monoid $\mathcal{DP}_n$ of all partial isometries on $\{1,\ldots,n\}$ and for its submonoid $\mathcal{ODP}_n$ of all order-preserving partial isometries.
Vitor H Fernandes +2 more
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2-hyperreflexivity and hyporeflexivity of power partial isometries [PDF]
Opuscula Mathematica, 2016 Power partial isometries are not always hyperreflexive neither reflexive. In the present paper it will be shown that power partial isometries are always hyporeflexive and \(2\)-hyperreflexive.
Kamila Piwowarczyk, Marek Ptak
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On families of twisted power partial isometries
Karpatsʹkì Matematičnì Publìkacìï, 2022 We consider families of power partial isometries satisfying twisted commutation relations with deformation parameters $\lambda_{ij}\in\mathbb C$, $|\lambda_{ij}|=1$.
V.L. Ostrovskyi +2 more
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Semigroups of partial isometries [PDF]
Semigroup Forum, 2013 We study self-adjoint semigroups of partial isometries on a Hilbert space. These semigroups coincide precisely with faithful representations of abstract inverse semigroups. Groups of unitary operators are specialized examples of self-adjoint semigroups of partial isometries. We obtain a general structure result showing that every self-adjoint semigroup
Popov AI, Radjavi H
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On partial isometries with circular numerical range
Concrete Operators, 2021 In their LAMA 2016 paper Gau, Wang and Wu conjectured that a partial isometry A acting on ℂn cannot have a circular numerical range with a non-zero center, and proved this conjecture for n ≤ 4. We prove it for operators with rank A = n − 1 and any n.
Wegert Elias, Spitkovsky Ilya
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Endomorphisms of the Toeplitz algebra
Учёные записки Казанского университета: Серия Физико-математические науки, 2023 This article describes all injective endomorphisms of the classical Toeplitz algebra. Their connection with endomorphisms of the algebra of continuous functions on the unit circle and with coverings over the unit circle was considered.
S. A. Grigoryan, A. Yu. Kuznetsova
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On the decomposition of families of quasinormal operators [PDF]
Opuscula Mathematica, 2013 The canonical injective decomposition of a jointly quasinormal family of operators is given. Relations between the decomposition of a quasinormal operator T and the decomposition of a partial isometry in the polar decomposition of T are described.
Zbigniew Burdak
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On a locally compact monoid of cofinite partial isometries of ℕ with adjoined zero
Topological Algebra and its Applications, 2022 Let 𝒞ℕ be a monoid which is generated by the partial shift α : n↦n +1 of the set of positive integers ℕ and its inverse partial shift β : n + 1 ↦n. In this paper we prove that if S is a submonoid of the monoid Iℕ∞ of all partial cofinite isometries of ...
Gutik Oleg, Khylynskyi Pavlo
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Factorization of matrices into partial isometries [PDF]
Proceedings of the American Mathematical Society, 1989 In this paper, we characterize complex square matrices which are expressible as products of partial isometries and orthogonal projections. More precisely, we show that a matrix T T
Kuo, Kunghwang, Wu, Peiyuan
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Characterization of pre-idempotent Copulas
Dependence Modeling, 2023 Copulas CC for which (CtC)2=CtC{({C}^{t}C)}^{2}={C}^{t}C are called pre-idempotent copulas, of which well-studied examples are idempotent copulas and complete dependence copulas.
Chamnan Wongtawan, Sumetkijakan Songkiat
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