English

The ultimate upper bound on the injectivity radius of the Stiefel manifold

Differential Geometry 2025-01-14 v3 Optimization and Control

Abstract

We exhibit conjugate points on the Stiefel manifold endowed with any member of the family of Riemannian metrics introduced by H\"uper et al. (2021). This family contains the well-known canonical and Euclidean metrics. An upper bound on the injectivity radius of the Stiefel manifold in the considered metric is then obtained as the minimum between the length of the geodesic along which the points are conjugate and the length of certain geodesic loops. Numerical experiments support the conjecture that the obtained upper bound is in fact equal to the injectivity radius.

Keywords

Cite

@article{arxiv.2403.02079,
  title  = {The ultimate upper bound on the injectivity radius of the Stiefel manifold},
  author = {P. -A. Absil and Simon Mataigne},
  journal= {arXiv preprint arXiv:2403.02079},
  year   = {2025}
}

Comments

Version accepted for publication in SIAM Journal on Matrix Analysis and Applications on 6 January 2025