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A symmetric hyperbolic formulation of the vacuum Einstein equations in affine-null coordinates

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 نشر من قبل Justin Ripley
 تاريخ النشر 2021
  مجال البحث فيزياء
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 تأليف Justin L. Ripley




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We present a symmetric hyperbolic formulation of the Einstein equations in affine-null coordinates. Giannakopoulos et. al. (arXiv:2007.06419) recently showed that the most commonly numerically implemented formulations of the Einstein equations in affine-null coordinates (and other single-null coordinate systems) are only weakly-but not strongly-hyperbolic. By making use of the tetrad-based Newman-Penrose formalism, our formulation avoids the hyperbolicity problems of the formulations investigated by Giannakopoulos et. al. We discuss a potential application of our formulation for studying gravitational wave scattering.



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