English

Exact boundary conditions in numerical relativity using multiple grids: scalar field tests

General Relativity and Quantum Cosmology 2009-11-11 v2

Abstract

Cauchy-Characteristic Matching (CCM), the combination of a central 3+1 Cauchy code with an exterior characteristic code connected across a time-like interface, is a promising technique for the generation and extraction of gravitational waves. While it provides a tool for the exact specification of boundary conditions for the Cauchy evolution, it also allows to follow gravitational radiation all the way to infinity, where it is unambiguously defined. We present a new fourth order accurate finite difference CCM scheme for a first order reduction of the wave equation around a Schwarzschild black hole in axisymmetry. The matching at the interface between the Cauchy and the characteristic regions is done by transfering appropriate characteristic/null variables. Numerical experiments indicate that the algorithm is fourth order convergent. As an application we reproduce the expected late-time tail decay for the scalar field.

Keywords

Cite

@article{arxiv.gr-qc/0604034,
  title  = {Exact boundary conditions in numerical relativity using multiple grids: scalar field tests},
  author = {Gioel Calabrese},
  journal= {arXiv preprint arXiv:gr-qc/0604034},
  year   = {2009}
}

Comments

14 pages, 5 figures. Included changes suggested by referees

R2 v1 2026-07-22T12:45:04.351Z