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arXiv · 1905.11401

Flexible and inflexible $CR$ submanifolds

Judith Brinkschulte·C. Denson Hill
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Abstract

In this paper we prove new embedding results for compactly supported deformations of $CR$ submanifolds of $\mathbb{C}^{n+d}$: We show that if $M$ is a $2$-pseudoconcave $CR$ submanifold of type $(n,d)$ in $\mathbb{C}^{n+d}$, then any compactly supported $CR$ deformation stays in the space of globally $CR$ embeddable in $\mathbb{C}^{n+d}$ manifolds. This improves an earlier result, where $M$ was assumed to be a quadratic $2$-pseudoconcave $CR$ submanifold of $\mathbb{C}^{n+d}$. We also give examples of weakly $2$-pseudoconcave $CR$ manifolds admitting compactly supported $CR$ deformations that are not even locally $CR$ embeddable.

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BibTeXRIS

Judith Brinkschulte, C. Denson Hill. 2019-05-27. Flexible and inflexible $CR$ submanifolds. https://arxiv.org/abs/1905.11401

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