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arXiv · 2201.08857

Bona-Masso slicing conditions and the lapse close to black-hole punctures

Thomas W. Baumgarte·Henrique P. de Oliveira
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Abstract

We consider several families of functions $f(\alpha)$ that appear in the Bona-Masso slicing condition for the lapse function $\alpha$. Focusing on spherically symmetric and time-independent slices we apply these conditions to the Schwarzschild spacetime in order to construct analytical expressions for the lapse $\alpha$ in terms of the areal radius $R$. We then transform to isotropic coordinates and determine the dependence of $\alpha$ on the isotropic radius $r$ in the vicinity of the black-hole puncture. We propose generalizations of previously considered functions $f(\alpha)$ for which, to leading order, the lapse is proportional to $r$ rather than a non-integer power of $r$. We also perform dynamical simulations in spherical symmetry and demonstrate advantages of the above choices in numerical simulations employing spectral methods.

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Thomas W. Baumgarte, Henrique P. de Oliveira. 2022-01-21. Bona-Masso slicing conditions and the lapse close to black-hole punctures. https://doi.org/10.1103/physrevd.105.064045

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