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arXiv · 2006.03464

The contact mappings of a flat $(2,3,5)$-distribution

Alex D. Austin
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Abstract

Let $\Omega$ and $\Omega'$ be open subsets of a flat $(2,3,5)$-distribution. We show that a $C^1$-smooth contact mapping $f : \Omega \to \Omega'$ is a $C^\infty$-smooth contact mapping. Ultimately, this is a consequence of the rigidity of the associated stratified Lie group (the Tanaka prolongation of the Lie algebra is of finite-type). The conclusion is reached through a careful study of some differential identities satisfied by components of the Pansu-derivative of a $C^1$-smooth contact mapping.

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Alex D. Austin. 2020-06-05. The contact mappings of a flat $(2,3,5)$-distribution. https://arxiv.org/abs/2006.03464

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