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arXiv · 2302.04513

On 3-nondegenerate CR manifolds in dimension 7 (I): the transitive case

Boris Kruglikov·Andrea Santi
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Abstract

We investigate 3-nondegenerate CR structures in the lowest possible dimension 7, and one of our goals is to prove Beloshapka's conjecture on the symmetry dimension bound for hypersurfaces in $\mathbb{C}^4$. We claim that 8 is the maximal symmetry dimension of 3-nondegenerate CR structures in dimension 7, which is achieved on the homogeneous model. This part (I) is devoted to the homogeneous case: we prove that the model is locally the only homogeneous 3-nondegenerate CR structure in dimension 7.

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Boris Kruglikov, Andrea Santi. 2023-02-09. On 3-nondegenerate CR manifolds in dimension 7 (I): the transitive case. https://arxiv.org/abs/2302.04513

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