Results 31 to 40 of about 448 (54)
Rank properties of exposed positive maps
, 2012 Let $\cK$ and $\cH$ be finite dimensional Hilbert spaces and let $\fP$ denote the cone of all positive linear maps acting from $\fB(\cK)$ into $\fB(\cH)$. We show that each map of the form $\phi(X)=AXA^*$ or $\phi(X)=AX^TA^*$ is an exposed point of $\fP$.
Eom MH +3 more
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Extensions of Three Matrix Inequalities to Semisimple Lie Groups
Special Matrices, 2014 We give extensions of inequalities of Araki-Lieb-Thirring, Audenaert, and Simon, in the context ofsemisimple Lie groups.
Liu Xuhua, Tam Tin-Yau
doaj +1 more source
A note on matrices mapping a positive vector onto its element-wise inverse
, 2017 For any primitive matrix $M\in\mathbb{R}^{n\times n}$ with positive diagonal entries, we prove the existence and uniqueness of a positive vector $\mathbf{x}=(x_1,\dots,x_n)^t$ such that $M\mathbf{x}=(\frac{1}{x_1},\dots,\frac{1}{x_n})^t$.
Labbé, Sébastien
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The 123 theorem of Probability Theory and Copositive Matrices
Special Matrices, 2014 Alon and Yuster give for independent identically distributed real or vector valued random variablesX, Y combinatorially proved estimates of the form Prob(∥X − Y∥ ≤ b) ≤ c Prob(∥X − Y∥ ≤ a). We derivethese using copositive matrices instead.
Kovačec Alexander +2 more
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Completely positive matrices over Boolean algebras and their CP-rank
Special Matrices, 2015 Drew, Johnson and Loewy conjectured that for n ≥ 4, the CP-rank of every n × n completely positive real matrix is at most [n2/4]. In this paper, we prove this conjecture for n × n completely positive matrices over Boolean algebras (finite or infinite ...
Mohindru Preeti
doaj +1 more source
Pure states proof of the Matrix-valued P\'olya Positivstellensatz
, 2023 Let $\Sigma$ denote the linear form $x_1 + \cdots + x_n$. By a classical Positivstellensatz of P\'olya, if a real form $f$ is strictly positive on the standard simplex, then $\Sigma^m f$ has strictly positive coefficients for some nonnegative integer $m$.
Tan, Colin
core
The integer cp-rank of 2 × 2 matrices
Special Matrices, 2019 We show the cp-rank of an integer doubly nonnegative 2 × 2 matrix does not exceed 11.
Laffey Thomas, Šmigoc Helena
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New approximations for the cone of copositive matrices and its dual
, 2012 We provide convergent hierarchies for the cone C of copositive matrices and its dual, the cone of completely positive matrices. In both cases the corresponding hierarchy consists of nested spectrahedra and provide outer (resp. inner) approximations for C
A Grundmann +16 more
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The critical exponent for generalized doubly nonnegative matrices
, 2016 It is known that the critical exponent (CE) for conventional, continuous powers of $n$-by-$n$ doubly nonnegative (DN) matrices is $n-2$. Here, we consider the larger class of diagonalizable, entry-wise nonnegative $n$-by-$n$ matrices with nonnegative ...
Han, Xuchen +2 more
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A p-adic Perron-Frobenius Theorem
, 2016 We prove that if an $n\times n$ matrix defined over ${\mathbb Q}_p$ (or more generally an arbitrary complete, discretely-valued, non-Archimedean field) satisfies a certain congruence property, then it has a strictly maximal eigenvalue in ${\mathbb Q}_p$,
Costa, Robert +2 more
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