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arXiv · 2402.08880

Solving the Einstein Constraints Numerically on Compact Three-Manifolds Using Hyperbolic Relaxation

Fan Zhang·Lee Lindblom
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Abstract

The effectiveness of the hyperbolic relaxation method for solving the Einstein constraint equations numerically is studied here on a variety of compact orientable three-manifolds. Convergent numerical solutions are found using this method on manifolds admitting negative Ricci scalar curvature metrics, i.e. those from the $H^3$ and the $H^2\times S^1$ geometrization classes. The method fails to produce solutions, however, on all the manifolds examined here admitting non-negative Ricci scalar curvatures, i.e. those from the $S^3$, $S^2\times S^1$, and the $E^3$ classes. This study also finds that the accuracy of the convergent solutions produced by hyperbolic relaxation can be increased significantly by performing fairly low-cost standard elliptic solves using the hyperbolic relaxation solutions as initial guesses.

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Fan Zhang, Lee Lindblom. 2024-02-14. Solving the Einstein Constraints Numerically on Compact Three-Manifolds Using Hyperbolic Relaxation. https://doi.org/10.1103/physrevd.109.064002

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