This paper expounds that besides the well-known spatio-temporal problem there is a causal problem of entanglement: even when one neglects spatio-temporal constraints, the peculiar statistics of EPR/B experiment is inconsistent with usual principles of causal explanation as stated by the theory of causal Bayes nets. The conflict amounts to a dilemma that either there are uncaused correlations (violating the causal Markov condition) or there are caused independences (violating the causal faithfulness condition). I argue that the central ideas of causal explanations can be saved if one accepts the latter horn and explains the unfaithful independences by a stable fine-tuning of the causal parameters.
KeywordsQuantum entanglement Bell theorem Scientific explanation Causal Bayes nets Causal Markov condition Causal faithfulness condition
I would like to thank Frederick Eberhardt, Alexander Gebharter, Clark Glymour, Kevin Kelly, Meinard Kuhlmann, Gerhard Schurz, Manfred Stöckler, Michael Zehetleitner and audiences at the Düsseldorf Center for Logic and Philosophy of Science, at the Munich Center for Mathematical Philosophy and at the Workshop ‘Physics and Causality’ (Deutsche Physikalische Gesellschaft, Munich, 2012) for helpful comments and discussion. Research for this paper was supported by the Deutsche Forschungsgemeinschaft (DFG).
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