Results 21 to 30 of about 221 (44)
On some classical trace inequalities and a new Hilbert-Schmidt norm inequality
, 2018 Let A be a positive semidefinite matrix and B be a Hermitian matrix. Using some classical trace inequalities, we prove, among other inequalities, that ∥ ∥AsB+BA1−s ∥ ∥ 2 ∥ ∥AtB+BA1−t ∥ ∥ 2 for 2 s t 1 . We conjecture that this inequality is also true for
M. Hayajneh, Saja Hayajneh, F. Kittaneh
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Orthogonal Representations, Projective Rank, and Fractional Minimum Positive Semidefinite Rank: Connections and New Directions [PDF]
, 2017 Fractional minimum positive semidefinite rank is defined from r-fold faithful orthogonal representations and it is shown that the projective rank of any graph equals the fractional minimum positive semidefinite rank of its complement.
Hogben, L +3 more
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A canonical form for H-unitary matrices
, 2016 In this paper matrices A are considered that have the property that A∗HA = H , where H = H∗ is invertible. A canonical form is given for the pair of matrices (A,H) under transformations (A,H) → (S−1AS,S∗HS) , where S is invertible, in which the canonical
G. Groenewald, D. V. Rensburg, A. Ran
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A constructive arbitrary-degree Kronecker product decomposition of tensors [PDF]
, 2016 We propose the tensor Kronecker product singular value decomposition~(TKPSVD) that decomposes a real $k$-way tensor $\mathcal{A}$ into a linear combination of tensor Kronecker products with an arbitrary number of $d$ factors $\mathcal{A} = \sum_{j=1}^R ...
Batselier, Kim, Wong, Ngai
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A simple sufficient condition for complete positivity
, 2015 We use row sums and rank to give a sufficient condition on the diagonal entries of a doubly nonnegative matrix for it to be completely positive and its cp-rank equal to its rank. Mathematics subject classification (2010): 15A23, 15B48, 15B57.
W. So, Changqing Xu
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PRESERVERS OF MATRIX PAIRS WITH A FIXED INNER PRODUCT VALUE
, 2012 Let V be the set of n×n hermitian matrices, the set of n×n symmetric matrices, the set of all effects, or the set of all projections of rank one. Let c be a real number. We characterize bijective maps φ : V → V satisfying tr (AB) = c ⇐⇒ tr (φ(A)φ(B)) = c
Chi-Kwong Li, Lucijan Plevnik, P. Šemrl
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A matrix-algebraic algorithm for the Riemannian logarithm on the Stiefel manifold under the canonical metric [PDF]
, 2017 We derive a numerical algorithm for evaluating the Riemannian logarithm on the Stiefel manifold with respect to the canonical metric. In contrast to the existing optimization-based approach, we work from a purely matrix-algebraic perspective.
Zimmermann, Ralf
core +2 more sources
Orthonormal Jordan bases in finite dimensional Hilbert spaces
, 2015 Necessary and sufficient conditions are presented for a linear operator in a finite dimensional complex or real Hilbert space to have a Jordan form in an orthonormal basis. Further, necessary conditions are given in terms of the self-commutator operator.
B. Nagy
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Concrete minimal 3 × 3 Hermitian matrices and some general cases
Demonstratio Mathematica, 2017 Given a Hermitian matrix M ∈ M3(ℂ) we describe explicitly the real diagonal matrices DM such that ║M + DM║ ≤ ║M + D║ for all real diagonal matrices D ∈ M3(ℂ), where ║ · ║ denotes the operator norm.
Klobouk Abel H., Varela Alejandro
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Nonnegative definite hermitian matrices with increasing principal minors
, 2013 A nonzero nonnegative definite hermitian m by m matrix A has increasing principal minors if the value of each principle minor of A is not less than the value each of its subminors. For $m>1$ we show $A$ has increasing principal minors if and only if $A^{-
Friedland, Shmuel
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