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Ambiguities in the derivation of retrodictive probability

K. A. Kirkpatrick
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Abstract

The derivation of the quantum retrodictive probability formula involves an error, an ambiguity. The end result is correct because this error appears twice, in such a way as to cancel itself. In addition, however, the usual expression for the probability itself contains the same ambiguity; this may lead to errors in its application. A generally applicable method is given to avoid such ambiguities altogether.

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K. A. Kirkpatrick. 2002-07-18. Ambiguities in the derivation of retrodictive probability. https://arxiv.org/abs/quant-ph/0207101

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