English

A Riemannian Corollary of Helly's Theorem

Metric Geometry 2019-10-03 v2 Data Structures and Algorithms

Abstract

We introduce a notion of halfspace for Hadamard manifolds that is natural in the context of convex optimization. For this notion of halfspace, we generalize a classic result of Gr\"unbaum, which itself is a corollary of Helly's theorem. Namely, given a probability distribution on the manifold, there is a point for which all halfspaces based at this point have at least 1n+1\frac{1}{n+1} of the mass. As an application, the gradient oracle complexity of convex optimization is polynomial in the parameters defining the problem.

Keywords

Cite

@article{arxiv.1804.10738,
  title  = {A Riemannian Corollary of Helly's Theorem},
  author = {Alexander Rusciano},
  journal= {arXiv preprint arXiv:1804.10738},
  year   = {2019}
}