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arXiv · 1708.01552

Bifurcation in Quantum Measurement

Karl-Erik Eriksson·Martin Cederwall·Kristian Lindgren·Erik Sjöqvist
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Abstract

We present a generic model of (non-destructive) quantum measurement. Being formulated within reversible quantum mechanics, the model illustrates a mechanism of a measurement process --- a transition of the measured system to an eigenstate of the measured observable. The model consists of a two-level system $\mu$ interacting with a larger system $A$, consisting of smaller subsystems. The interaction is modelled as a scattering process. Restricting the states of $A$ to product states leads to a bifurcation process: In the limit of a large system $A$, the initial states of $A$ that are efficient in leading to a final state are divided into two separated subsets. For each of these subsets, $\mu$ ends up in one of the eigenstates of the measured observable. The probabilities obtained in this branching confirm the Born rule.

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Karl-Erik Eriksson, Martin Cederwall, Kristian Lindgren, Erik Sjöqvist. 2017-08-04. Bifurcation in Quantum Measurement. https://arxiv.org/abs/1708.01552

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