2-positive almost order zero maps and decomposition rank

Yasuhiko Sato

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arXiv · 1908.03466

2-positive almost order zero maps and decomposition rank

Yasuhiko Sato

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Abstract

We consider 2-positive almost order zero (disjointness preserving) maps on C*-algebras. Generalizing the argument of M. Choi for multiplicative domains, we give an internal characterization of almost order zero for 2-positive maps. It is also shown that complete positivity can be reduced to 2-positivity in the definition of decomposition rank for unital separable C*-algebras.

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Yasuhiko Sato. 2019-08-09. 2-positive almost order zero maps and decomposition rank. https://arxiv.org/abs/1908.03466

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