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arXiv · 2510.26902

An extendible spacetime without closed timelike curves whose every extension contains closed timelike curves

H. Andréka·J. Madarász·J. Manchak·I. Németi·G. Székely
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Abstract

By removing a fractal from time-rolled Minkowski spacetime, we construct an extendible spacetime without closed timelike curves whose every extension contains closed timelike curves. This settles a question posed by Geroch.

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H. Andréka, J. Madarász, J. Manchak, I. Németi, G. Székely. 2025-10-30. An extendible spacetime without closed timelike curves whose every extension contains closed timelike curves. https://doi.org/10.1007/s10701-026-00914-0

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