The convexity radius of a Riemannian manifold

James Dibble

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arXiv · 1412.0341

The convexity radius of a Riemannian manifold

James Dibble

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Abstract

The ratio of convexity radius over injectivity radius may be made arbitrarily small within the class of compact Riemannian manifolds of any fixed dimension at least two. This is proved using Gulliver's method of constructing manifolds with focal points but no conjugate points. The approach is suggested by a characterization of the convexity radius that resembles a classical result of Klingenberg about the injectivity radius.

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James Dibble. 2014-12-01. The convexity radius of a Riemannian manifold. https://arxiv.org/abs/1412.0341

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