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arXiv · 1002.3913

What are the systems that decohere?

Mario Castagnino·Sebastian Fortin·Olimpia Lombardi
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Abstract

The fact that the Environment Induced Decoherence approach offers no general criterion to decide where to place the "cut" between system and environment has been considered as a serious conceptual problem of the proposal. In this letter we argue that this is actually a pseudo-problem, which is dissolved by the fact that decoherence is a phenomenon relative to the relevant observables selected by the measuring arrangement. We also show that, when the spin-bath model is studied from this perspective, certain unexpected results are obtained, as that of a system decohering in interaction with a very small environment.

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Mario Castagnino, Sebastian Fortin, Olimpia Lombardi. 2010-02-20. What are the systems that decohere?. https://arxiv.org/abs/1002.3913

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