Results 231 to 240 of about 7,615 (257)

Distance to the convex hull of the unitary orbit with respect to unitary similarity invariant norms

Linear and Multilinear Algebra, 1989
Let A B be Hermitian matrices. Denote by co the convex hull of the unitary orbit of B. We determine the matrices BM and Bm in co such that for all X∊ co and all unitary similarity invariant norms ∣∣sdot;∣∣, ie., those norms ∣∣sdot;∣∣ satisfying ∣∣UXU ∗∣∣=∣∣X∣∣ for any Hermitian X and unitary U.
Chi-Kwong Li, Nam-Kiu Tsing
openaire   +1 more source

Unitary similarity comparison of persistent homology groups

Japan Journal of Industrial and Applied Mathematics
Jiaxing He, Bingzhe Hou, Wu Tieru
exaly   +2 more sources

Unitary similarity of matrices with simple eigenvalues

Doklady Mathematics, 2011
Matrices \(A, B \in M_n(\mathbb{C})\) are unitarily similar if there exists an unitary matrix \(U\) such that \(B=UAU^*\). This paper deals with the verification of matrices for unitary similarity. Based on other authors' works concerning this problem, a basic approach consists of constructing a canonical form of matrices with respect to unitary ...
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Image hiding using unitary similarity transformation

2011 International Conference on Image Information Processing, 2011
A different and efficient method of image hiding is proposed here. It is based on unitary similarity transformation, involving calculation of eigen values and eigen vectors of a matrix and then transforming it into a diagonal matrix. Only secret image needs to be transformed and is then embedded to the cover image. Inverse transformation can be used to
Manoj Sharma, Manoj Shukla, Amit Kaul
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Unitary similarity of algebras generated by pairs of orthoprojectors

Journal of Mathematical Sciences, 2006
Summary: It is shown that the unitary similarity of two matrix algebras generated by pairs of orthoprojectors \(\{P_1,Q_1\}\) and \(\{P_2,Q_2\}\) can be verified by comparing the traces of \(P_1\), \(Q_1\), and \((P_1 Q_1)^i\), \(i= 1,2,\dots,n\), with those of \(P_2\), \(Q_2\), and \((P_2Q_2)^i\).
Al'pin Y., Ikramov K.
openaire   +4 more sources

Unitary similarity and the numerical radius preservers

Linear Algebra and its Applications
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Abdellatif Bourhim, Mohamed Mabrouk
openaire   +1 more source

Contractions being Weakly Similar to Unitaries

1986
In this paper contractions being weakly similar in a certain sense to unitary operators are studied. Extending the investigations of [12], where only cyclic contractions were considered, it is examined when a contraction T, weakly similar to unitary possesses the bicommutant property Alg T = {T}″. Finally, a characterization of cyclic C11 -contractions
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Conditions for similarity to unitary and self-adjoint operators

Functional Analysis and Its Applications, 1984
In this article the new integral conditions \(\sup_{| \lambda | >1}(| \lambda |^ 2-1)\int^{2\pi}_{0}\| (T-\lambda)^{- 1}u\|^ 2d\theta \leq C\| u\|^ 2\) and \(\sup_{| \lambda | >1}(1-| \lambda |^{-2})\int^{2\pi}_{0}\| (T^*- \lambda)^{-1}u\|^ 2d\theta \leq C\| u\|^ 2\) (u\(\in H)\) on the resolvent of the operator T are given, necessary and sufficient ...
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Polar Decomposition And Dense Similarity To Unitary Operators

1993
Prigogine and Misra have shown that any K-dynamical system is densely similar to a Markov process converging to equilibrium. In their construction the self-adjoint operator realizing the dense similarity is a function of the positive part of the polar form of the Markov operator. In this work we show that this property holds in a very general framework.
N. Bertoglio, S. Martínez, J. San Martín   +2 more
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Similarity and Unitary Equivalence

2022
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