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Stern-Gerlach Experiment and Bohm Limit

Marco Frasca
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Abstract

Stern-Gerlach experiment is a paradigm of measurement theory in quantum mechanics. Notwithstanding several analysis given in literature, no clear understanding of the apparent collapse has been given so far. Indeed, one can imagine a Stern-Gerlach device where all environmental effects are removed and ask the question on how the measurement goes on. In this letter we will prove that a the Stern-Gerlach device behaves as a true measurement apparatus, as expected by the Copenaghen interpretation, by the Ehrenfest theorem. In this way we recover, by other means, a limit on the Stern-Gerlach device, given by Bohm, based on scrambling of phases due to a large oscillation frequency.

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Marco Frasca. 2004-02-10. Stern-Gerlach Experiment and Bohm Limit. https://arxiv.org/abs/quant-ph/0402072

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