Topology and Closed Timelike Curves II: Causal structure

Hunter Monroe

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arXiv · gr-qc/0607134

Topology and Closed Timelike Curves II: Causal structure

Hunter Monroe

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Abstract

Because no closed timelike curve (CTC) on a Lorentzian manifold can be deformed to a point, any such manifold containing a CTC must have a topological feature, to be called a timelike wormhole, that prevents the CTC from being deformed to a point. If all wormholes have horizons, which typically seems to be the case in space-times without exotic matter, then each CTC must transit some timelike wormhole's horizon. Therefore, a Lorentzian manifold containing a CTC may nevertheless be causally well behaving once its horizon's are deleted. For instance, there may be a Cauchy-like surface through which every timelike curve passes one and only once before crossing a horizon.

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Hunter Monroe. 2006-09-14. Topology and Closed Timelike Curves II: Causal structure. https://arxiv.org/abs/gr-qc/0607134

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