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arXiv · 2207.06376

Shock-avoiding slicing conditions: tests and calibrations

Thomas W. Baumgarte·David Hilditch
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Abstract

While the 1+log slicing condition has been extremely successful in numerous numerical relativity simulations, it is also known to develop "gauge-shocks" in some examples. Alternative "shock-avoiding" slicing conditions suggested by Alcubierre prevent these pathologies in those examples, but have not yet been explored and tested very broadly. In this paper we compare the performance of shock-avoiding slicing conditions with those of 1+log slicing for a number of "text-book" problems, including black holes and relativistic stars. While, in some simulations, the shock-avoiding slicing conditions feature some unusual properties and lead to more "gauge-dynamics" than the 1+log slicing condition, we find that they perform quite similarly in terms of stability and accuracy, and hence provide a very viable alternative to 1+log slicing.

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Thomas W. Baumgarte, David Hilditch. 2022-07-13. Shock-avoiding slicing conditions: tests and calibrations. https://doi.org/10.1103/physrevd.106.044014

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