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arXiv · 2001.02343

Some applications of two completely copositive maps

Yongtao Li·Yang Huang·Lihua Feng·Weijun Liu
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Abstract

A linear map $\Phi :\mathbb{M}_n \to \mathbb{M}_k$ is called completely copositive if the resulting matrix $[\Phi (A_{j,i})]_{i,j=1}^m$ is positive semidefinite for any integer $m$ and positive semidefinite matrix $[A_{i,j}]_{i,j=1}^m$. In this paper, we present some applications of the completely copositive maps $\Phi (X)=(\mathrm{tr} X)I+X$ and $\Psi (X)= (\mathrm{tr} X)I-X$. Some new extensions about traces inequalities of positive semidefinite $3\times 3$ block matrices are included.

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Yongtao Li, Yang Huang, Lihua Feng, Weijun Liu. 2020-01-08. Some applications of two completely copositive maps. https://doi.org/10.1016/j.laa.2019.12.036

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