Funk Metrics and R-Flat Sprays

Zhongmin Shen

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arXiv · math/0109037

Funk Metrics and R-Flat Sprays

Zhongmin Shen

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Abstract

The well-known Funk metric F(x,y) is projectively flat with constant flag curvature K=-1/4 and the Hilbert metric H(x,y):=(F(x,y)+F(x,-y))/2 is projectively flat with constant curvature K=-1. These metrics are the special solutions to Hilbert's Fourth Problem. In this paper, we construct a non-trivial R-flat spray using the Funk metric. It is then an inverse problem in the calculus of variation to find a Finsler metric that induces the R-flat spray. We find an explicit solution to this inverse problem and obtain a non-trivial projectively flat Finsler metric with K=0.

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BibTeX RIS

Zhongmin Shen. 2001-09-05. Funk Metrics and R-Flat Sprays. https://arxiv.org/abs/math/0109037

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