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arXiv · 2204.06740

The Fate of Causal Structure under Time Reversal

Porter Williams
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Abstract

What happens to the causal structure of a world when time is reversed? At first glance it seems there are two possible answers: the causal relations are reversed, or they are not. I argue that neither of these answers is correct: we should either deny that time-reversed worlds have causal relations at all, or deny that causal concepts developed in the actual world are reliable guides to the causal structure of time-reversed worlds. The first option is motivated by the instability under intervention of time-reversed dynamical evolutions. The second option is motivated by a recognition of how contingent structural features of the actual world shape, and license the application of, our causal concepts and reasoning strategies.

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Porter Williams. 2022-04-14. The Fate of Causal Structure under Time Reversal. https://arxiv.org/abs/2204.06740

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