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Mean king's problem with mutually unbiased bases and orthogonal Latin squares

A. Hayashi·M. Horibe·T. Hashimoto
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Abstract

The mean king's problem with maximal mutually unbiased bases (MUB's) in general dimension d is investigated. It is shown that a solution of the problem exists if and only if the maximal number (d+1) of orthogonal Latin squares exists. This implies that there is no solution in d=6 or d=10 dimensions even if the maximal number of MUB's exists in these dimensions.

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A. Hayashi, M. Horibe, T. Hashimoto. 2005-06-10. Mean king's problem with mutually unbiased bases and orthogonal Latin squares. https://doi.org/10.1103/physreva.71.052331

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