Results 31 to 40 of about 49,764 (200)
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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On the closure of the completely positive semidefinite cone and linear approximations to quantum colorings [PDF]
, 2015 We investigate structural properties of the completely positive semidefinite cone $\mathcal{CS}_+^n$, consisting of all the $n \times n$ symmetric matrices that admit a Gram representation by positive semidefinite matrices of any size. This cone has been
Burgdorf, Sabine +2 more
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Singularity Degree of the Positive Semidefinite Matrix Completion Problem [PDF]
SIAM Journal on Optimization, 2017 The singularity degree of a semidefinite programming problem is the smallest number of facial reduction steps to make the problem strictly feasible. We introduce two new graph parameters, called the singularity degree and the nondegenerate singularity degree, based on the singularity degree of the positive semidefinite matrix completion problem.
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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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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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Bounds of the logarithmic mean [PDF]
, 2013 We give tight bounds for logarithmic mean. We also give new Frobenius norm inequalities for two positive semidefinite matrices. In addition, we give some matrix inequalities on matrix power mean.Comment: The second assertion in (i) of Proposition 5.2 was
Furuichi, Shigeru, Yanagi, Kenjiro
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RisksWe devise two algorithms for approximating solutions of PSDisation, a problem in actuarial science and finance, to find the nearest valid correlation matrix that is positive semidefinite (PSD).
Vali Asimit +3 more
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Positive Maps and Separable Matrices
, 2016 A linear map between real symmetric matrix spaces is positive if all positive semidefinite matrices are mapped to positive semidefinite ones. A real symmetric matrix is separable if it can be written as a summation of Kronecker products of positive ...
Nie, Jiawang, Zhang, Xinzhen
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Positive semidefinite matrix supermartingales
Electronic Journal of ProbabilityEJP.
Wang, Hongjian, Ramdas, Aaditya
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Fast implementation for semidefinite programs with positive matrix completion [PDF]
Optimization Methods and Software, 2015 Solving semidefinite programs (SDP) in a short time is the key to managing various mathematical optimization problems. The matrix-completion primal-dual interior-point method (MC-PDIPM) extracts a sparse structure of input SDP by factorizing the variable matrices. In this paper, we propose a new factorization based on the inverse of the variable matrix
Makoto Yamashita, Kazuhide Nakata
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