Distance Matrix of a Class of Completely Positive Graphs: Determinant and Inverse
Special Matrices, 2020 A real symmetric matrix A is said to be completely positive if it can be written as BBt for some (not necessarily square) nonnegative matrix B. A simple graph G is called a completely positive graph if every matrix realization of G that is both ...
Das Joyentanuj +2 more
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Convergence of block iterative methods for linear systems arising in the numerical solution of Euler equations [PDF]
, 1991 Elsner L, Mehrmann V. Convergence of block iterative methods for linear systems arising in the numerical solution of Euler equations. Numerische Mathematik.
Mehrmann, Volker, Elsner, Ludwig
core +1 more source
A counterexample to the Drury permanent conjecture
Special Matrices, 2017 We offer a counterexample to a conjecture concerning the permanent of positive semidefinite matrices. The counterexample is a 4 × 4 complex correlation matrix.
Hutchinson George
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Existence and Uniqueness of the Positive Definite Solution for the Matrix Equation X=Q+A∗(X^−C)−1A
Abstract and Applied Analysis, 2013 We consider the nonlinear matrix equation X=Q+A∗(X^−C)−1A, where Q is positive definite, C is positive semidefinite, and X^ is the block diagonal matrix defined by X^=diag(X,X,…,X).
Dongjie Gao
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A trace bound for integer-diagonal positive semidefinite matrices
Special Matrices, 2020 We prove that an n-by-n complex positive semidefinite matrix of rank r whose graph is connected, whose diagonal entries are integers, and whose non-zero off-diagonal entries have modulus at least one, has trace at least n + r − 1.
Mitchell Lon
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A time-dependent regularization of the Redfield equation
SciPost Physics, 2023 We introduce a new regularization of the Redfield equation based on a replacement of the Kossakowski matrix with its closest positive semidefinite neighbor.
Antonio D'Abbruzzo, Vasco Cavina, Vittorio Giovannetti
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Separability for mixed states with operator Schmidt rank two [PDF]
Quantum, 2019 The operator Schmidt rank is the minimum number of terms required to express a state as a sum of elementary tensor factors. Here we provide a new proof of the fact that any bipartite mixed state with operator Schmidt rank two is separable, and can be ...
Gemma De las Cuevas +2 more
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Gap inequalities for non-convex mixed-integer quadratic programs [PDF]
, 2011 Laurent and Poljak introduced a very general class of valid linear inequalities, called gap inequalities, for the max-cut problem. We show that an analogous class of inequalities can be defined for general non-convex mixed-integer quadratic programs ...
Galli, Laura +8 more
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Complexity of the Positive Semidefinite Matrix Completion Problem with a Rank Constraint [PDF]
, 2013 18 pages, 3 ...
M. Eisenberg-Nagy (Marianna) +2 more
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Positive semidefinite matrix supermartingales
Electronic Journal of ProbabilityEJP.
Wang, Hongjian, Ramdas, Aaditya
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