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arXiv · 2302.00524

Normal forms for the sub-Riemannian exponential map of $\mathbb{G}_\alpha$, $\mathrm{SU}(2)$, and $\mathrm{SL}(2)$

Samuël Borza
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Abstract

The goal of this paper is to use singularity theory to find normal forms near the critical points of the sub-Riemannian exponential map. Three cases are studied: the $\alpha$-Grushin plane with fold singularities, and the special unitary group $\mathrm{SU}(2)$ and special linear group $\mathrm{SL}(2)$ with fold and saddle-like singularities. They serve as examples of different sub-Riemannian structures and the techniques presented can be applied to other contexts. The paper also includes a discussion of the implications of this approach, as well as open problems.

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Samuël Borza. 2023-02-01. Normal forms for the sub-Riemannian exponential map of $\mathbb{G}_\alpha$, $\mathrm{SU}(2)$, and $\mathrm{SL}(2)$. https://arxiv.org/abs/2302.00524

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