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arXiv · 1111.6523

Isometric embeddings of 2-spheres by embedding flow for applications in numerical relativity

Michael Jasiulek·Mikolaj Korzynski
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Abstract

We present a numerical method for solving Weyl's embedding problem which consists of finding a global isometric embedding of a positively curved and positive-definite spherical 2-metric into the Euclidean three space. The method is based on a construction introduced by Weingarten and was used in Nirenberg's proof of Weyl's conjecture. The target embedding results as the endpoint of an embedding flow in R^3 beginning at the unit sphere's embedding. We employ spectral methods to handle functions on the surface and to solve various (non)-linear elliptic PDEs. Possible applications in 3+1 numerical relativity range from quasi-local mass and momentum measures to coarse-graining in inhomogeneous cosmological models.

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Michael Jasiulek, Mikolaj Korzynski. 2011-11-28. Isometric embeddings of 2-spheres by embedding flow for applications in numerical relativity. https://doi.org/10.1088/0264-9381%2F29%2F15%2F155010

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