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Are gauge shocks really shocks?

Miguel Alcubierre
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Abstract

The existence of gauge pathologies associated with the Bona-Masso family of generalized harmonic slicing conditions is proven for the case of simple 1+1 relativity. It is shown that these gauge pathologies are true shocks in the sense that the characteristic lines associated with the propagation of the gauge cross, which implies that the name ``gauge shock'' usually given to such pathologies is indeed correct. These gauge shocks are associated with places where the spatial hypersurfaces that determine the foliation of spacetime become non-smooth.

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Miguel Alcubierre. 2005-08-24. Are gauge shocks really shocks?. https://doi.org/10.1088/0264-9381%2F22%2F19%2F017

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