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Probability in decoherent histories

Todd A. Brun
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Abstract

The decoherent (consistent) histories formalism has been proposed as a means of eliminating measurements as a fundamental concept in quantum mechanics. In this formalism, probabilities can be assigned to any description which satisfies a particular consistency condition. The formalism, however, admits incompatible descriptions which cannot be combined, unlike classical physics. This seems to leave an ambiguity in the choice of the description. I argue that this ambiguity is removed by considering the observer as a physical system.

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Todd A. Brun. 2003-02-04. Probability in decoherent histories. https://arxiv.org/abs/quant-ph/0302034

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