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TESTING March 05, 2026

Order Unit Spaces and Probabilistic Models

Authors

John Harding, Alex Wilce

Abstract

We exhibit a functor from the category OUS of order unit spaces and positive, unit-preserving mappings into the category $\Prob$ of probabilistic models (test spaces with designated state spaces) and morphisms thereof. Restricted to any subcategory of OUS monoidal with respect to a positive, normalized, bilinear composition rule, our functor is also monoidal. This shows that the convex-operational approach to physical theories can be subsumed by the test-space approach, without resort to ``generalized test spaces''. A second construction, equipping a probabilistic model with tests representing ``weighted coins'', also sheds light on the nature of unsharp observables.

Metadata

arXiv ID: 2603.05682
Provider: ARXIV
Primary Category: quant-ph
Published: 2026-03-05
Fetched: 2026-03-09 06:05

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Raw Data (Debug)
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