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Impact of densitized lapse slicings on evolutions of a wobbling black hole

U. Sperhake·K. L. Smith·B. Kelly·P. Laguna·D. Shoemaker
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Abstract

We present long-term stable and second-order convergent evolutions of an excised wobbling black hole. Our results clearly demonstrate that the use of a densitized lapse function extends the lifetime of simulations dramatically. We also show the improvement in the stability of single static black holes when an algebraic densitized lapse condition is applied. In addition, we introduce a computationally inexpensive approach for tracking the location of the singularity suitable for mildly distorted black holes. The method is based on investigating the fall-off behavior and asymmetry of appropriate grid variables. This simple tracking method allows one to adjust the location of the excision region to follow the coordinate motion of the singularity.

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U. Sperhake, K. L. Smith, B. Kelly, P. Laguna, D. Shoemaker. 2003-07-03. Impact of densitized lapse slicings on evolutions of a wobbling black hole. https://doi.org/10.1103/physrevd.69.024012

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