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Symmetry, Rationality, and the Born Rule

David Wallace

Published May 24, 2012• 0 citations

Abstract

Building on work originally carried out by David Deutsch, the chapter develops a mathematically rigorous framework for discussing the quantum probability rule in terms of the preferences between various courses of action of rational agents. Within this framework, the chapter proves formally that any rational agent who believes in the truth of Everettian quantum mechanics and who knows (or thinks they know) the current quantum state of their branch will act as if future branching was a probabilistic process with the probabilities given by the standard quantum-mechanical probability rule (the ‘Born rule’). The chapter concludes by analysing other proposed rules for action in a quantum universe and showing where they violate the axioms for quantum decision making which it proposes and defends.

DOI: 10.1093/acprof:oso/9780199546961.003.0007

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