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arXiv · 2311.06606

Comment on "Continuous simultaneous measurement of position and momentum of a particle"

Adélcio C. Oliveira
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Abstract

In a recent paper, [Gampel, F. and Gajda, M., Phys. Rev. A 107, 012420, (2023)], the authors claimed they are proposing a new model to explain the existence of classical trajectories in the quantum domain. The idea is based on simultaneous position and momentum measurements and a "jump Markov process". Consequently, they have interpreted the emergence of classical trajectories as sets of detection events. They successfully implemented the model for a free particle and for one under a harmonic potential. Here, we show that the continuous observation limit is a realization of a coherent semiclassical expansion; Also, as has already been demonstrated, the jump process is not necessary and is not observable. In other words, the collapse, as they propose, is a non-go theorem; even if it is real, it can not be measured under the needed assumptions to obtain Newtonian classical dynamics.

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Adélcio C. Oliveira. 2023-11-11. Comment on "Continuous simultaneous measurement of position and momentum of a particle". https://arxiv.org/abs/2311.06606

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