Essay on Restoring the quantum state after a measurement by Stephen Parrott
نویسنده
چکیده
It was selected as the subject of a “Viewpoint” article in the APS expository journal Physics [2]. The article is available online without a subsciption at physics.aps.org/articles/v1/34 . I will give some quotes from the article below, but the reader is urged to first read the original. The Katz, et al., article describes an experiment in which a measurement on a quantum state was “undone”, yielding a state identical to the one before the measurement. According to quantum theory as typically presented in older texts which consider only “projective” measurements, this should be impossible. Both the original Katz, et al., article and the Viewpoint speak of the supposedly impossible restoration as having something to do with so-called “weak measurements” and erasure of information. Here are some quotes from the Viewpoint:
منابع مشابه
Comments on the Referee's Reports for Manuscript Foop1369, Submitted to Foundations of Physics, Entitled Quantum Weak Values Are Not Unique What Do They Actually Measure?
Most of the comments on the referee's reports will not be meaningful to someone who has not read the paper, so I may as well use the notation of the paper. For the reader's convenience, it is summarized below, but most readers will probably want to skip the summary, referring back to it only if needed. Symbols in the summary (such as A, s, f , etc.) will be used in the comments without further ...
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