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Cauchy-characteristic Evolution of Einstein-Klein-Gordon Systems: The Black Hole Regime

Philippos Papadopoulos·Pablo Laguna
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Abstract

The Cauchy+characteristic matching (CCM) problem for the scalar wave equation is investigated in the background geometry of a Schwarzschild black hole. Previously reported work developed the CCM framework for the coupled Einstein-Klein-Gordon system of equations, assuming a regular center of symmetry. Here, the time evolution after the formation of a black hole is pursued, using a CCM formulation of the governing equations perturbed around the Schwarzschild background. An extension of the matching scheme allows for arbitrary matching boundary motion across the coordinate grid. As a proof of concept, the late time behavior of the dynamics of the scalar field is explored. The power-law tails in both the time-like and null infinity limits are verified.

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Philippos Papadopoulos, Pablo Laguna. 1996-10-31. Cauchy-characteristic Evolution of Einstein-Klein-Gordon Systems: The Black Hole Regime. https://doi.org/10.1103/physrevd.55.2038

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