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Hilbert metrics and Minkowski norms

Thomas Foertsch·Anders Karlsson
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Abstract

It is shown that the Hilbert geometry $(D,h_D)$ associated to a bounded convex domain $D\subset \mathbb{E}^n$ is isometric to a normed vector space $(V,||\cdot ||)$ if and only if $D$ is an open $n$-simplex. One further result on the asymptotic geometry of Hilbert's metric is obtained with corollaries for the behavior of geodesics. Finally we prove that every geodesic ray in a Hilbert geometry converges to a point of the boundary.

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Thomas Foertsch, Anders Karlsson. 2004-07-12. Hilbert metrics and Minkowski norms. https://arxiv.org/abs/math/0407197

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