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Optimal estimation of an observable's expectation value for pure states for general measure of deviation

Minoru Horibe·Akihisa Hayashi·Takaaki Hashimoto
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Abstract

We investigate the optimal estimation of quantum expectation value of a physical observable, which minimizes a mean error with respect to general measure of deviation, when a finite number of copies of a pure state are prepared. If pure sates are uniformly distributed, the minimum value of mean error for any measure of deviation is achieved by projective measurement on each copy.

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Minoru Horibe, Akihisa Hayashi, Takaaki Hashimoto. 2006-10-03. Optimal estimation of an observable's expectation value for pure states for general measure of deviation. https://arxiv.org/abs/quant-ph/0610014

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