Leaks: quantum, classical, intermediate, and more

John Selby; Bob Coecke

doi:10.3390/e19040174

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arXiv · 1701.07404

Leaks: quantum, classical, intermediate, and more

John Selby·Bob Coecke

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Abstract

We introduce the notion of a leak for general process theories, and identify quantum theory as a theory with minimal leakage, while classical theory has maximal leakage. We provide a construction that adjoins leaks to theories, an instance of which describes the emergence of classical theory by adjoining decoherence-leaks to quantum theory. Finally, we show that defining a notion of purity for processes in general process theories has to make reference to the leaks of that theory ---a feature missing in standard definitions--- hence, we propose a refined definition and study the resulting notion of purity for quantum, classical and intermediate theories.

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John Selby, Bob Coecke. 2017-01-25. Leaks: quantum, classical, intermediate, and more. https://doi.org/10.3390/e19040174

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