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arXiv · 0911.1208

Gowdy waves as a test-bed for constraint-preserving boundary conditions

C. Bona·C. Bona-Casas
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Abstract

Gowdy waves, one of the standard 'apples with apples' tests, is proposed as a test-bed for constraint-preserving boundary conditions in the non-linear regime. As an illustration, energy-constraint preservation is separately tested in the Z4 framework. Both algebraic conditions, derived from energy estimates, and derivative conditions, deduced from the constraint-propagation system, are considered. The numerical errors at the boundary are of the same order than those at the interior points.

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C. Bona, C. Bona-Casas. 2009-11-06. Gowdy waves as a test-bed for constraint-preserving boundary conditions. https://doi.org/10.1088/1742-6596%2F229%2F1%2F012022

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