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On free evolution of self gravitating, spherically symmetric waves

Mirta S. Iriondo·Oscar A. Reula
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Abstract

We perform a numerical free evolution of a selfgravitating, spherically symmetric scalar field satisfying the wave equation. The evolution equations can be written in a very simple form and are symmetric hyperbolic in Eddington-Finkelstein coordinates. The simplicity of the system allow to display and deal with the typical gauge instability present in these coordinates. The numerical evolution is performed with a standard method of lines fourth order in space and time. The time algorithm is Runge-Kutta while the space discrete derivative is symmetric (non-dissipative). The constraints are preserved under evolution (within numerical errors) and we are able to reproduce several known results.

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Mirta S. Iriondo, Oscar A. Reula. 2001-02-07. On free evolution of self gravitating, spherically symmetric waves. https://doi.org/10.1103/physrevd.65.044024

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