Contact real hypersurfaces in the complex hyperbolic quadric

Abstract

We give a new proof of the classification of contact real hypersurfaces with constant mean curvature in the complex hyperbolic quadric ${Q^m}^* = SO_{m,2}^o/SO_mSO_2$, where $m\geq 3$. We show that a contact real hypersurface $M$ in ${Q^m}^*$ for $m\geq 3$ is locally congruent to a tube of radius $r{\in}{\mathbb R}^+$ around the complex hyperbolic quadric ${Q^{m-1}}^*$, or to a tube of radius $r\in\mathbb{R}^+$ around the $\mathfrak A$-principal $m$-dimensional real hyperbolic space ${\mathbb R}H^m$ in ${Q^m}^* = SO_{m,2}^o/SO_mSO_2$, or to a horosphere in ${Q^{m-1}}^*$ induced by a class of $\mathfrak A$-principal geodesics in ${Q^m}^*$.

Extensive revision of the first version. The Introduction has been rewritten completely, in particular including a reference to an earlier proof of the classification. Section 2 has been rewritten to replace the incorrect model of the complex hyperbolic quadric from v1 with a correct one. Sections 4 and 5 have also been revised to make the arguments clearer and easier to understand. 24 pages