Results 41 to 50 of about 5,889,360 (355)
New Sufficient Condition for the Positive Definiteness of Fourth Order Tensors
Mathematics, 2018 In this paper, we give a new Z-eigenvalue localization set for Z-eigenvalues of structured fourth order tensors. As applications, a sharper upper bound for the Z-spectral radius of weakly symmetric nonnegative fourth order tensors is obtained and a new Z-
Jun He +3 more
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Многоязычие в образовательном пространстве, 2021 The purpose of this study is to conduct a comparative typological analysis of the means of expressing the category “Definiteness / Indefiniteness” in German, Tatar and Russian languages and, building on this analysis, to develop a system of exercises ...
A. A. Sibgatullina
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Inertia, positive definiteness and $\ell_p$ norm of GCD and LCM matrices and their unitary analogs [PDF]
, 2017 Let $S=\{x_1,x_2,\dots,x_n\}$ be a set of distinct positive integers, and let $f$ be an arithmetical function. The GCD matrix $(S)_f$ on $S$ associated with $f$ is defined as the $n\times n$ matrix having $f$ evaluated at the greatest common divisor of ...
Haukkanen, Pentti, Tóth, László
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Classification of positive definite lattices [PDF]
Duke Mathematical Journal, 2000 35 pages, plain ...
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Remedies for Misapplications of Sylvester’s Criterion: A Pedagogic Illustration
Spreadsheets in Education, 2021 Sylvester’s criterion, which verifies the positive definiteness of any real symmetric matrix by examining the signs of all leading principal minors, is an excellent analytical tool.
Clarence C.Y. Kwan
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A new positive definite geometric mean of two positive definite matrices
Linear Algebra and its Applications, 1997 The authors introduce a new type of geometric mean of two positive definite (under certain conditions, positive semidefinite) matrices and describe its most important properties. This new concept of a geometric mean is also confronted with the mean introduced by \textit{T. Ando} [Topics on operator inequalities (1978; Zbl 0388.47024)].
Vlastimil Pták, Miroslav Fiedler
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Intelligent optimization based density matrix reconstruction method with semi-positive constraint
Results in Physics, 2023 Quantum state tomography (QST) is a technique used to reconstruct the density matrix of unknown quantum states based on experimentally obtained measurements. QST is a fundamental tool in the field of quantum information and quantum technology.
Xiaomin Meng +3 more
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Positive definiteness and positive differences
Journal of Combinatorial Theory, Series A, 1972 AbstractA previous inequality [2] in certain context, which holds in the application to the monotonicity of correlations in classical discrete Heisenberg ferromagnets with 2-dimensional spin [3], is extended to positive definiteness of a function on a group.
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Positive Semidefiniteness and Positive Definiteness of a Linear Parametric Interval Matrix
, 2017 We consider a symmetric matrix, the entries of which depend linearly on some parameters. The domains of the parameters are compact real intervals. We investigate the problem of checking whether for each (or some) setting of the parameters, the matrix is ...
A Neumaier +30 more
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Computational geometry of positive definiteness
Linear Algebra and its Applications, 2012 AbstractIn matrix computations, such as in factoring matrices, Hermitian and, preferably, positive definite elements are occasionally required. Related problems can often be cast as those of existence of respective elements in a matrix subspace. For two dimensional matrix subspaces, first results in this regard are due to Finsler.
Seiskari, Otto, Huhtanen, Marko
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