Many Worlds, the Born Rule, and Self-Locating Uncertainty

  • Sean M. CarrollEmail author
  • Charles T. Sebens


We provide a derivation of the Born Rule in the context of the Everett (Many-Worlds) approach to quantum mechanics. Our argument is based on the idea of self-locating uncertainty: in the period between the wave function branching via decoherence and an observer registering the outcome of the measurement, that observer can know the state of the universe precisely without knowing which branch they are on. We show that there is a uniquely rational way to apportion credence in such cases, which leads directly to the Born Rule. [Editors note: for a video of the talk given by Prof. Carroll at the Aharonov-80 conference in 2012 at Chapman University, see]


Wave Function Hilbert Space Quantum Mechanic Unitary Transformation Unitary Evolution 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



Sean Carroll feels that it has been an honor and a pleasure to take part in the celebration of Yakir Aharonov’s 80th birthday and would like to thank Jeff Tollaksen and the organizers of a very stimulating meeting. His work was supported in part by the U.S. Department of Energy, the National Science Foundation, and the Gordon and Betty Moore Foundation. Charles Sebens’s work was supported by the National Science Foundation Graduate Research Fellowship under Grant No. DGE 0718128.


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Copyright information

© Springer-Verlag Italia 2014

Authors and Affiliations

  1. 1.Physics DepartmentCalifornia Institute of TechnologyPasadenaUSA
  2. 2.Philosophy DepartmentUniversity of MichiganAnn ArborUSA

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