Decoherence as a relative phenomenon: a generalization of the spin-bath model

Mario Castagnino; Sebastian Fortin; Olimpia Lombardi

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arXiv · 0907.1933

Decoherence as a relative phenomenon: a generalization of the spin-bath model

Mario Castagnino·Sebastian Fortin·Olimpia Lombardi

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Abstract

In this paper we propose a closed-system perspective to study decoherence. From this perspective we analyze the spin-bath model as presented in the literature, and a natural generalization of that model. On the basis of the results obtained from that analysis, we argue that decoherence may be understood as a phenomenon relative to the partition of a closed system, selected in each particular case. This viewpoint frees the decoherence program from certain conceptual difficulties derived from its open-system perspective. We also argue that the usual picture of decoherence in terms of energy dissipation is misguided.

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Mario Castagnino, Sebastian Fortin, Olimpia Lombardi. 2009-07-11. Decoherence as a relative phenomenon: a generalization of the spin-bath model. https://arxiv.org/abs/0907.1933

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