Probabilities, Causes and Propensities in Physics pp 115-155 | Cite as

# On Explanation in Retro-causal Interpretations of Quantum Mechanics

## Abstract

The curious correlations between distant events in quantum phenomena suggest the existence of non-local influences. Indeed, as John Bell demonstrated in his celebrated theorem, granted some plausible premises any quantum theory will predict the existence of such non-local influences. One of the theorem’s premises is that the probability distribution of the states that systems may assume is independent of the measurements that they undergo at a later time. Retro-causal interpretations of quantum mechanics postulate backward influences from measurement events to the state of systems at an earlier time, and accordingly violate this premise. We argue that retro-causal interpretations predict the existence of closed causal loops, and consider the challenges that these loops for the explanatory power of these interpretations.

## Keywords

Bohmian Mechanic Standard Quantum Mechanic Causal Loop Block Universe Orthodox Interpretation## Notes

### Acknowledgements

The work on this paper was prompted by an invitation to contribute to this volume. I am very grateful to the editor, Mauricio Suarez. Parts of this paper were presented at the Time-Symmetric Interpretations of Quantum Mechanics Workshop and the Summer Foundations Conference 2006, Centre for Time, Department of Philosophy, University of Sydney; CREA, Polytechnique, Paris; the Department of Philosophy, Universidad de Barcelona; the Department of Philosophy, Universidad Complutense de Madrid; and the Sigma Club, Centre for the Philosophy of Natural and Social Sciences, London School of Economics. These conferences and colloquia were instrumental in the development of the paper, and I thank the organizers, audiences, and in particular Rod Sutherland, Mauricio Suarez, Huw Price, David Miller, Carl Hoefer, Roman Frigg and Guido Bacciagaluppi. For support, I am very grateful to the Department of Philosophy, University of Sydney, and the Institute for History and Philosophy of Science and Technology, University of Toronto.

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