Curvature estimates for hypersurfaces of constant curvature in hyperbolic space II
Bin Wang
TL;DR
The work addresses the existence of smooth complete hypersurfaces in $\mathbb{H}^{n+1}$ with constant curvature given by symmetric functions of the hyperbolic principal curvatures and prescribed asymptotic boundary data. It advances the curvature-estimate backbone by deriving global $C^2$ bounds for two important classes: (i) the $(n-2)$-curvature equation with $f=H_{n-2}^{1/(n-2)}$ and (ii) quotient-type equations $f=(H_k/H_l)^{1/(k-l)}$, under suitable convexity and boundary hypotheses. The authors obtain a sharp curvature bound of the form $\max_{\Sigma} \kappa_{\max} \le C(1+\max_{\partial\Sigma}\kappa_{\max})$ by deploying the Guan–Spruck framework, refined concavity inequalities (Ren–Wang), and careful analysis of the associated fully nonlinear PDE, including a maximum-principle argument on a suitably chosen test function. These curvature estimates pave the way for existence results for all $\sigma\in(0,1)$ in the considered cones $K_k$, significantly extending prior results that required restricted ranges of $\sigma$, and they articulate a concrete path toward a general quotient-cone existence theory in hyperbolic space.
Abstract
In this note, we investigate the existence of smooth complete hypersurfaces in hyperbolic space with constant curvature and a prescribed asymptotic boundary at infinity. By deriving curvature estimates, we are able to deduce the existence in some cases. Previously, these existence results were proved for a restricted range of curvature values, while here we prove the existence for all possible curvature values.
