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Consistent Quantum Counterfactuals

Robert B. Griffiths
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Abstract

An analysis using classical stochastic processes is used to construct a consistent system of quantum counterfactual reasoning. When applied to a counterfactual version of Hardy's paradox, it shows that the probabilistic character of quantum reasoning together with the ``one framework'' rule prevents a logical contradiction, and there is no evidence for any mysterious nonlocal influences. Counterfactual reasoning can support a realistic interpretation of standard quantum theory (measurements reveal what is actually there) under appropriate circumstances.

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Robert B. Griffiths. 1999-09-15. Consistent Quantum Counterfactuals. https://doi.org/10.1103/physreva.60.r5

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