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arXiv · 2106.02101

The Weyl problem for unbounded convex domains in $\HH^3$

Abstract

Let $K\subset \HH^3$ be a convex subset in $\HH^3$ with smooth, strictly convex boundary. The induced metric on $\partial K$ then has curvature $K>-1$. It was proved by Alexandrov that if $K$ is bounded, then it is uniquely determined by the induced metric on the boundary, and any smooth metric with curvature $K>-1$ can be obtained. We propose here an extension of the existence part of this result to unbounded convex domains in $\HH^3$. The induced metric on $\partial K$ is then clearly not sufficient to determine $K$. However one can consider a richer data on the boundary including the ideal boundary of $K$. Specifically, we consider the data composed of the full conformal structure on the boundary of $K$ (in the Poincar\'e model of $\HH^3$), together with the induced metric on $\partial K$. We show that a wide range of "reasonable" data of this type, satisfying mild curvature conditions, can be realized on the boundary of a convex subset in $\HH^3$.

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Jean-Marc Schlenker. 2021-06-03. The Weyl problem for unbounded convex domains in $\HH^3$. https://arxiv.org/abs/2106.02101

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