Mixing and decoherence to nearest separable states in quantum measurements

Avijit Lahiri

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arXiv · 0705.0733

Mixing and decoherence to nearest separable states in quantum measurements

Avijit Lahiri

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Abstract

We illustrate through numerical results a number of features of environment-induced decoherence under a broad class of apparatus-environment interactions in quantum measurements wherein the reduced system-apparatus density matrix evolves towards the nearest separable state and, in addition, there occurs a mixing in relevant groups of apparatus microstates (see below). The resulting final state is unique and correctly embodies the measurement statistics even in the absence of environment-induced superselection because of energy differences between these groups of states. The partial transpose remains non-positive throughout the process.

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Avijit Lahiri. 2007-05-26. Mixing and decoherence to nearest separable states in quantum measurements. https://arxiv.org/abs/0705.0733

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