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Directly Observing Momentum Transfer in Twin-Slit "Which-Way" Experiments

H. M. Wiseman
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Abstract

Is the destruction of interference by a which-way measurement due to a random momentum transfer $\wp\agt\hbar/s$, with $s$ the slit separation? The weak-valued probability distribution $P_{\rm wv}(\wp)$, which is {\em directly observable}, provides a subtle answer. $P_{\rm wv}(\wp)$ cannot have support on the interval $[-\hbar/s,\hbar/s]$. Nevertheless, its moments can be identically zero.

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H. M. Wiseman. 2003-03-23. Directly Observing Momentum Transfer in Twin-Slit "Which-Way" Experiments. https://doi.org/10.1016/s0375-9601(03)00504-8

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