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A new time-machine model with compact vacuum core

Amos Ori
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Abstract

We present a class of curved-spacetime vacuum solutions which develope closed timelike curves at some particular moment. We then use these vacuum solutions to construct a time-machine model. The causality violation occurs inside an empty torus, which constitutes the time-machine core. The matter field surrounding this empty torus satisfies the weak, dominant, and strong energy conditions. The model is regular, asymptotically-flat, and topologically-trivial. Stability remains the main open question.

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Amos Ori. 2005-03-17. A new time-machine model with compact vacuum core. https://doi.org/10.1103/physrevlett.95.021101

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