We demonstrate how General Relativity allows for the coordinate-velocity of light to change, and how in theory this may lead to effectively “faster-than-light” travel schemes. Such effectively “faster-than-light travel” schemes can lead to time-travel as a side effect. This is shown via a simple animated model.

This model is published in the research journal: Classical and Quantum Gravity. The full published research paper may be found here (open access):
https://arxiv.org/abs/1708.09505

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