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Accurate quantum state estimation via "Keeping the experimentalist honest"

Robin Blume-Kohout·Patrick Hayden
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Abstract

In this article, we derive a unique procedure for quantum state estimation from a simple, self-evident principle: an experimentalist's estimate of the quantum state generated by an apparatus should be constrained by honesty. A skeptical observer should subject the estimate to a test that guarantees that a self-interested experimentalist will report the true state as accurately as possible. We also find a non-asymptotic, operational interpretation of the quantum relative entropy function.

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Robin Blume-Kohout, Patrick Hayden. 2006-03-14. Accurate quantum state estimation via "Keeping the experimentalist honest". https://arxiv.org/abs/quant-ph/0603116

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