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arXiv · 1511.08785

Speed addition and closed time cycle in Lorentz-non-invariant theories

Anatoly E. Shabad
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Abstract

In theories, whose Lorentz invariance is violated by involvement of an external any-rank tensor, we show that the standard relativistic rule still holds true for summing the signal speed, understood as the group velocity of a wave, with the speed of the reference frame. Provided a superluminal signal is available, this observation enables one to arrange a closed time cycle and hence causality violation, notwithstanding the Lorentz noninvariance. Also an optical anisotropy of a moving medium, isotropic at rest, is revealed.

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Anatoly E. Shabad. 2015-11-27. Speed addition and closed time cycle in Lorentz-non-invariant theories. https://doi.org/10.1134/s0040577916060027

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