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arXiv · 1711.10257

On the role of the measurement apparatus in quantum measurements

Muzaffar Qadir Lone·Chris Nagele·Brad Weslake·Tim Byrnes
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Abstract

We study the extent to which the outcomes of a quantum measurement can be manipulated by changing the state of the measurement apparatus. The measurement process is modeled as decoherence induced by the experimenter, to gain knowledge about a particular system. The measurement apparatus is assumed to contain a large number of degrees of freedom, and the measurement outcomes are obtained by looking at the long interaction time limit. We study two cases which show contrasting behaviour. With a fixed axis coupling, the measurement is performed along the pointer basis with a high degree of robustness, for a wide variety of bath states. In a second model with Heisenberg interactions, the measurement outcomes can be altered considerably by changing the state of the bath.

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Muzaffar Qadir Lone, Chris Nagele, Brad Weslake, Tim Byrnes. 2017-11-28. On the role of the measurement apparatus in quantum measurements. https://arxiv.org/abs/1711.10257

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