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Observational Consequences of Many-Worlds Quantum Theory

Don N. Page
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Abstract

Contrary to an oft-made claim, there can be observational distinctions (say for the expansion of the universe or the cosmological constant) between "single-history" quantum theories and "many-worlds" quantum theories. The distinctions occur when the number of observers is not uniquely predicted by the theory. In single-history theories, each history is weighted simply by its quantum-mechanical probability, but in many-worlds theories in which random observations are considered, there should also be the weighting by the numbers or amounts of observations occurring in each history.

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Don N. Page. 1999-05-03. Observational Consequences of Many-Worlds Quantum Theory. https://arxiv.org/abs/quant-ph/9904004

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