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Extending Heisenberg's measurement--disturbance relation to the twin-slit case

H. M. Wiseman
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Abstract

Heisenberg's position-measurement--momentum-disturbance relation is derivable from the uncertainty relation $σ(q)σ(p) \geq \hbar/2$ only for the case when the particle is initially in a momentum eigenstate. Here I derive a new measurement--disturbance relation which applies when the particle is prepared in a twin-slit superposition and the measurement can determine at which slit the particle is present. The relation is $d \times Δp \geq 2\hbar/π$, where $d$ is the slit separation and $Δp=D_{M}(P_{f},P_{i})$ is the Monge distance between the initial $P_{i}(p)$ and final $P_{f}(p)$ momentum distributions.

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H. M. Wiseman. 2002-10-10. Extending Heisenberg's measurement--disturbance relation to the twin-slit case. https://arxiv.org/abs/quant-ph/0210065

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