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Adaptive mesh refinement approach to construction of initial data for black hole collisions

Peter Diener·Nina Jansen·Alexei Khokhlov·Igor Novikov
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Abstract

The initial data for black hole collisions is constructed using a conformal-imaging approach and a new adaptive mesh refinement technique, a fully threaded tree (FTT). We developed a second-order accurate approach to the solution of the constraint equations on a non-uniformly refined high resolution Cartesian mesh including second-order accurate treatment of boundary conditions at the black hole throats. Results of test computations show convergence of the solution as the numerical resolution is increased. FTT-based mesh refinement reduces the required memory and computer time by several orders of magnitude compared to a uniform grid. This opens up the possibility of using Cartesian meshes for very high resolution simulations of black hole collisions.

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Peter Diener, Nina Jansen, Alexei Khokhlov, Igor Novikov. 1999-05-20. Adaptive mesh refinement approach to construction of initial data for black hole collisions. https://doi.org/10.1088/0264-9381%2F17%2F2%2F312

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