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arXiv · 1504.01590

How many orthonormal bases are needed to distinguish all pure quantum states?

Claudio Carmeli·Teiko Heinosaari·Jussi Schultz·Alessandro Toigo
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Abstract

We collect some recent results that together provide an almost complete answer to the question stated in the title. For the dimension d=2 the answer is three. For the dimensions d=3 and d>4 the answer is four. For the dimension d=4 the answer is either three or four. Curiously, the exact number in d=4 seems to be an open problem.

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Claudio Carmeli, Teiko Heinosaari, Jussi Schultz, Alessandro Toigo. 2015-04-07. How many orthonormal bases are needed to distinguish all pure quantum states?. https://doi.org/10.1140/epjd%2Fe2015-60230-5

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