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

TL;DR

This paper presents a new perspective on decoherence as a relative phenomenon depending on system partitioning, challenging traditional open-system views and the emphasis on energy dissipation.

Contribution

It generalizes the spin-bath model and introduces a closed-system approach to understanding decoherence as relative to system partitioning.

Findings

Decoherence depends on how the system is partitioned.

The traditional open-system and energy dissipation views are challenged.

A generalized spin-bath model supports the relative decoherence perspective.

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.