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arXiv · 1308.4557

Completely positive projections and biproducts

Chris Heunen·Aleks Kissinger·Peter Selinger
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Abstract

The recently introduced CP*-construction unites quantum channels and classical systems, subsuming the earlier CPM-construction in categorical quantum mechanics. We compare this construction to two earlier attempts at solving this problem: freely adding biproducts to CPM, and freely splitting idempotents in CPM. The CP*-construction embeds the former, and embeds into the latter, but neither embedding is an equivalence in general.

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Chris Heunen, Aleks Kissinger, Peter Selinger. 2014-12-30. Completely positive projections and biproducts. https://doi.org/10.4204/eptcs.171.7

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