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arXiv · 1706.07389

Graph products of completely positive maps

Scott Atkinson
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Abstract

We define the graph product of unital completely positive maps on a universal graph product of unital C*-algebras and show that it is unital completely positive itself. To accomplish this, we introduce the notion of the non-commutative length of a word, and we obtain a Stinespring construction for concatenation. This result yields the following consequences. The graph product of positive-definite functions is positive-definite. A graph product version of von Neumann's Inequality holds. Graph independent contractions on a Hilbert space simultaneously dilate to graph independent unitaries.

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Scott Atkinson. 2017-06-22. Graph products of completely positive maps. https://arxiv.org/abs/1706.07389

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