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arXiv · 2006.16576

Higher order Levi forms on homogeneous CR manifolds

Stefano Marini·Costantino Medori·Mauro Nacinovich
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Abstract

We investigate the nondegeneracy of higher order Levi forms on weakly nondegenerate homogeneous $CR$ manifolds. Improving previous results, we prove that general orbits of real forms in complex flag manifolds have order less or equal $3$ and the compact ones less or equal~$2$. Finally we construct by Lee extensions weakly nondegenerate $CR$ vector bundles with arbitrary orders of nondegeneracy.

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Stefano Marini, Costantino Medori, Mauro Nacinovich. 2020-06-30. Higher order Levi forms on homogeneous CR manifolds. https://arxiv.org/abs/2006.16576

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