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Upper bound on our knowledge about noncommuting observables for a qubit system

Yuji Kurotani·Takahiro Sagawa·Masahito Ueda
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Abstract

A trade-off relation on our knowledge about two noncommuting observables of a qubit system in simultaneous measurement is formulated. The obtained inequality offers a quantitative information-theoretic representation of Bohr's principle of complementarity, and can be interpreted as a trade-off relation on the asymptotic accuracy of the maximum-likelihood estimation of the probability distributions of observables.

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Yuji Kurotani, Takahiro Sagawa, Masahito Ueda. 2007-09-10. Upper bound on our knowledge about noncommuting observables for a qubit system. https://doi.org/10.1103/physreva.76.022325

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