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arXiv · 1702.01845

Updating the Born rule

Sally Shrapnel·Fabio Costa·Gerard Milburn
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Abstract

Despite the tremendous empirical success of quantum theory there is still widespread disagreement about what it can tell us about the nature of the world. A central question is whether the theory is about our knowledge of reality, or a direct statement about reality itself. Regardless of their stance on this question, current interpretations of quantum theory regard the Born rule as fundamental and add an independent state-update (or "collapse") rule to describe how quantum states change upon measurement. In this paper we present an alternative perspective and derive a probability rule that subsumes both the Born rule and the collapse rule. We show that this more fundamental probability rule can provide a rigorous foundation for informational, or "knowledge-based", interpretations of quantum theory.

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Sally Shrapnel, Fabio Costa, Gerard Milburn. 2017-02-07. Updating the Born rule. https://doi.org/10.1088/1367-2630/aabe12

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