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arXiv · 2307.02034

Diagonal and off-diagonal blocks of positive definite partitioned matrices

Jean-Christophe Bourin·Eun-Young Lee
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Abstract

We establish a sharp inequality between the blocks of positive partitioned matrices and conjecture a triangle type inequality for contractions: Given three contactions A,B,C, we conjecture that the constant c=3/4 is sharp in the triangle inequality |A+B+C| < cI + |A| +|B| + |C|.

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Jean-Christophe Bourin, Eun-Young Lee. 2023-07-05. Diagonal and off-diagonal blocks of positive definite partitioned matrices. https://arxiv.org/abs/2307.02034

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