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arXiv · 2303.17090

No-go result for quantum postselection measurements of rank-m degenerate subspace

Le Bin Ho
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Abstract

We present a no-go result for postselection measurements where the conditional expectation value of a joint system-device observable under postselection is nothing else than the conventional expectation value. Such a no-go result relies on the rank-m degenerate of the joint observable, where m is the dimension of the device subspace. Remarkable, we show that the error and disturbance in quantum measurements obey the no-go result, which implies that the error-disturbance uncertainty is unaffected under postselection measurements.

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Le Bin Ho. 2023-03-30. No-go result for quantum postselection measurements of rank-m degenerate subspace. https://doi.org/10.1103/physreva.107.042204

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