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arXiv · 1005.2828

Nonlinear evolution of coarse-grained quantum systems with generalized purity constraints

Nikola Buric
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Abstract

Constrained quantum dynamics is used to propose a nonlinear dynamical equation for pure states of a generalized coarse-grained system. The relevant constraint is given either by the generalized purity or by the generalized invariant fluctuation, and the coarse-grained pure states correspond to the generalized coherent i.e. generalized nonentangled states. Open system model of the coarse-graining is discussed. It is shown that in this model and in the weak coupling limit the constrained dynamical equations coincide with an equation for pointer states, based on Hilbert-Schmidt distance, that was previously suggested in the context of the decoherence theory.

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Nikola Buric. 2010-05-17. Nonlinear evolution of coarse-grained quantum systems with generalized purity constraints. https://doi.org/10.1016/j.physleta.2010.11.003

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