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arXiv · 1608.05614

All measurements in a probabilistic theory are compatible if and only if the state space is a simplex

Martin Plávala
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Abstract

We study the compatibility of measurements on finite-dimensional compact convex state space in the framework of general probabilistic theory. Our main emphasis is on formulation of necessary and sufficient conditions for two-outcome measurements to be compatible and we use these conditions to show that there exist incompatible measurements whenever the state space is not a simplex. We also formulate the linear programming problem for the compatibility of two-outcome measurements.

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Martin Plávala. 2016-08-18. All measurements in a probabilistic theory are compatible if and only if the state space is a simplex. https://doi.org/10.1103/physreva.94.042108

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