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Spectral methods in general relativity -- toward the simulation of 3D-gravitational collapse of neutron stars

S. Bonazzola·J. Frieben·E. Gourgoulhon·J. A. Marck
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Abstract

Several applications of spectral methods to problems related to the relativistic astrophysics of compact objects are presented. Based on a proper definition of the analytical properties of regular tensorial functions we have developed a spectral method in a general sphericallike coordinate system. The applications include the investigation of spherically symmetric neutron star collapse as well as the solution of the coupled 2D-Einstein-Maxwell equations for magnetized, rapidly rotating neutron stars. In both cases the resulting codes are efficient and give results typically several orders of magnitude more accurate than equivalent codes based on finite difference schemes. We further report the current status of a 3D-code aiming at the simulation of non-axisymmetric neutron star collapse where we have chosen a tensor based numerical scheme.

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S. Bonazzola, J. Frieben, E. Gourgoulhon, J. A. Marck. 1996-04-12. Spectral methods in general relativity -- toward the simulation of 3D-gravitational collapse of neutron stars. https://arxiv.org/abs/gr-qc/9604029

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