Results 31 to 40 of about 221 (44)
Sufficient conditions for complete positivity
, 2011 Marcus and Minc gave sufficient conditions on the diagonal entries of a doubly nonnegative doubly stochastic n×n matrix A , that there is a doubly nonnegative doubly stochastic matrix C with A = C2 . In this event, A is completely positive.
Robert Reams
semanticscholar +1 more source
On the Principal Permanent Rank Characteristic Sequences of Graphs and Digraphs
, 2015 The principal permanent rank characteristic sequence is a binary sequence $r_0 r_1 \ldots r_n$ where $r_k = 1$ if there exists a principal square submatrix of size $k$ with nonzero permanent and $r_k = 0$ otherwise, and $r_0 = 1$ if there is a zero ...
Horn, Paul +5 more
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Linear preservers and quantum information science
, 2012 Let $m,n\ge 2$ be positive integers, $M_m$ the set of $m\times m$ complex matrices and $M_n$ the set of $n\times n$ complex matrices. Regard $M_{mn}$ as the tensor space $M_m\otimes M_n$. Suppose $|\cdot|$ is the Ky Fan $k$-norm with $1 \le k \le mn$, or
Fosner, Ajda +3 more
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Patterns with several multiple eigenvalues
Special Matrices, 2014 Identified are certain special periodic diagonal matrices that have a predictable number of pairedeigenvalues. Since certain symmetric Toeplitz matrices are special cases, those that have several multiple 5eigenvalues are also investigated further.
Dorsey J., Johnson C.R., Wei Z.
doaj +1 more source
Jordan triple product homomorphisms on Hermitian matrices to and from dimension one
, 2015 We characterise all Jordan triple product homomorphisms, that is, mappings $\Phi$ satisfying $$ \Phi(ABA) = \Phi(A)\Phi(B)\Phi(A) $$ from the set of all Hermitian $n \times n$ complex matrices to the field of complex numbers.
Bukovsek, Damjana Kokol, Mojskerc, Blaz
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Existence of a Not Necessarily Symmetric Matrix with Given Distinct Eigenvalues and Graph
, 2016 For given k distinct complex conjugate pairs, l distinct real numbers, and a given graph G on 2k+l vertices with a matching of size at least k, we will show that there is a real matrix whose eigenvalues are the given numbers and its graph is G.
Monfared, Keivan Hassani
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Hermitian symmetric polynomials and CR complexity
, 2010 Properties of Hermitian forms are used to investigate several natural questions from CR Geometry. To each Hermitian symmetric polynomial we assign a Hermitian form.
D. Catlin +19 more
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On the Laplacian index of tadpole graphs
Special MatricesIn this article, we study the Laplacian index of tadpole graphs, which are unicyclic graphs formed by adding an edge between a cycle Ck{C}_{k} and a path Pn{P}_{n}.
Braga Rodrigo O., Veloso Bruno S.
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Geometric approaches to matrix normalization and graph balancing
Forum of Mathematics, SigmaNormal matrices, or matrices which commute with their adjoints, are of fundamental importance in pure and applied mathematics. In this paper, we study a natural functional on the space of square complex matrices whose global minimizers are normal ...
Tom Needham, Clayton Shonkwiler
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Hermitian unitary matrices with modular permutation symmetry
, 2015 We study Hermitian unitary matrices $\mathcal{S}\in\mathbb{C}^{n,n}$ with the following property: There exist $r\geq0$ and $t>0$ such that the entries of $\mathcal{S}$ satisfy $|\mathcal{S}_{jj}|=r$ and $|\mathcal{S}_{jk}|=t$ for all $j,k=1,\ldots,n$, $j\
Anderson +23 more
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