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arXiv · 2303.07635

Time Travel Paradoxes and Entangled Timelines

Barak Shoshany·Zipora Stober
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Abstract

For time travel to be consistent with the known laws of physics, the resulting paradoxes must be resolved. It has been suggested that parallel timelines (a.k.a. multiple histories) may provide a resolution. However, so far, a concrete mechanism by which parallel timelines can be created has never been satisfactorily formulated. In this paper we propose such a mechanism based on the Everett (many-worlds) interpretation of quantum mechanics, together with a linear pure-state CTC consistency condition. The timelines in our model are emergent, like the "worlds" of the Everett interpretation; they are created by the entanglement of the time machine with the environment and the resulting decoherence. Therefore, we call them "entangled timelines" or E-CTCs. As the entanglement gradually spreads out to additional systems, the timelines spread out as well, providing a local and well-defined alternative to the naive "branching timelines" picture often presented in the literature. The E-CTC model is similar to Deutsch's familiar D-CTC model, but differs from it mainly by keeping the entangled state explicit and imposing a different consistency condition. These differences allow us to create a clearer practical definition of the resulting parallel timelines.

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Barak Shoshany, Zipora Stober. 2023-03-14. Time Travel Paradoxes and Entangled Timelines. https://arxiv.org/abs/2303.07635

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