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Gangster operators and invincibility of positive semidefinite matrices - MaRDI portal

Gangster operators and invincibility of positive semidefinite matrices (Q603139)

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scientific article; zbMATH DE number 5811027
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Gangster operators and invincibility of positive semidefinite matrices
scientific article; zbMATH DE number 5811027

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    Gangster operators and invincibility of positive semidefinite matrices (English)
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    5 November 2010
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    It is not always true that after replacing in a positive semidefinite (\(psd\)) matrix \(A\) an opposite pair of entries by zero the matrix stays \(psd\). Call this operation of replacement a gangster operation (shooting holes in the matrix). In this paper properties of this operation are studied. This is one such problem: A \(psd\) matrix is called fully invincible if all gangster operations lead to \(psd\) matrices. This property is characterized. This has to do with M-matrices and comparison matrices.
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    gangster operator
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    invincible matrix
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    positive semidefinite matrix
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    M-matrices
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    comparison matrices
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