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A210532
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Minimum number of observables that need to be measured in order to uniquely determine an n-dimensional quantum state that is known a priori to be pure.
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0
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OFFSET
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2,1
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LINKS
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FORMULA
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23 <= a(8) <= 24
4n - 5 - log_2(n) <= a(n) <= 4n - 5 for all n >= 2. More precise bounds are given in the Heinosaari paper.
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EXAMPLE
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In the n = 2 case, you need to measure all a(2) = 3 linearly independent observables (e.g., the Pauli X, Y, and Z operators) in order to uniquely specify all pure states.
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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STATUS
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approved
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