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Interaction-free measurement and forward scattering

Tamás Geszti
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Abstract

Interaction-free measurement is shown to arise from the forward-scattered wave accompanying absorption: a "quantum silhouette" of the absorber. Accordingly, the process is not free of interaction. For a perfect absorber the forward-scattered wave is locked both in amplitude and in phase. For an imperfect one it has a nontrivial phase of dynamical origin (``colored silhouette"), measurable by interferometry. Other examples of quantum silhouettes, all controlled by unitarity, are briefly discussed.

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Tamás Geszti. 1998-04-23. Interaction-free measurement and forward scattering. https://doi.org/10.1103/physreva.58.4206

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