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The close limit from a null point of view: the advanced solution

Manuela Campanelli·Roberto Gomez·Sascha Husa·Jeffrey Winicour·Yosef Zlochower
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Abstract

We present a characteristic algorithm for computing the perturbation of a Schwarzschild spacetime by means of solving the Teukolsky equation. We implement the algorithm as a characteristic evolution code and apply it to compute the advanced solution to a black hole collision in the close approximation. The code successfully tracks the initial burst and quasinormal decay of a black hole perturbation through 10 orders of magnitude and tracks the final power law decay through an additional 6 orders of magnitude. Determination of the advanced solution, in which ingoing radiation is absorbed by the black hole but no outgoing radiation is emitted, is the first stage of a two stage approach to determining the retarded solution, which provides the close approximation waveform with the physically appropriate boundary condition of no ingoing radiation.

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Manuela Campanelli, Roberto Gomez, Sascha Husa, Jeffrey Winicour, Yosef Zlochower. 2001-06-07. The close limit from a null point of view: the advanced solution. https://doi.org/10.1103/physrevd.63.124013

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