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arXiv · 1908.04234

Excision and avoiding the use of boundary conditions in numerical relativity

Justin L. Ripley
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Abstract

A procedure for evolving hyperbolic systems of equations on compact computational domains with no boundary conditions was recently described in [arXiv:1905.08657]. In that proposal, the computational grid is expanded in spacelike directions with respect to the outermost characteristic and initial data is imposed on the expanded grid boundary. We discuss a related method that removes the need for imposing boundary conditions: the computational domain is excised along a direction spacelike with respect to the innermost going characteristic. We compare the two methods, and provide example evolutions from a code that implements the excision method: evolution of a massless self-gravitating scalar field in spherical symmetry.

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Justin L. Ripley. 2019-08-12. Excision and avoiding the use of boundary conditions in numerical relativity. https://doi.org/10.1088/1361-6382%2Fab51a7

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