Homogeneous Levi degenerate CR-manifolds in dimension 5

Gregor Fels; Wilhelm Kaup

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Homogeneous Levi degenerate CR-manifolds in dimension 5

Gregor Fels·Wilhelm Kaup

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Abstract

We investigate CR-manifolds which are tubes M:= F x iV over general bases F in a real vector space V and characterize the k-nondegeneracy of M in terms of the real affine geometry of F. We give a method for an explicit computation of the Lie algebra hol(M,a) of all local infinitesimal CR-transformations at a and use these local invariants to establish the CR-inequivalence of certain families of CR-manifolds. In dimension 5 we present, apart from the well known tube over the future light cone, new examples of 2-nondegenerate homogeneous CR-manifolds that are mutually locally CR-inequivalent.

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Gregor Fels, Wilhelm Kaup. 2006-02-01. Homogeneous Levi degenerate CR-manifolds in dimension 5. https://arxiv.org/abs/math/0602030

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