Curvature estimates for minimal hypersurfaces in the Heisenberg group
Gianmarco Giovannardi, Andrea Pinamonti, Simone Verzellesi
TL;DR
This work studies minimal hypersurfaces in sub-Riemannian Heisenberg groups, extending the classical Simons identity and Kato inequalities to the horizontal setting. By deriving a full sub-Riemannian Simons identity and its contracted form, together with improved Kato-type estimates, the authors obtain integral curvature bounds for stable non-characteristic hypersurfaces and formulate a stability framework suited to Carnot groups. Under natural structural assumptions and a volume-growth condition, they prove a Bernstein-type rigidity in ${\mathbb H}^2$, showing that complete, stable non-characteristic hypersurfaces must be vertical hyperplanes, thereby advancing the understanding of sub-Riemannian Bernstein problems. The results provide new analytic tools for curvature control in the Heisenberg sense and offer a pathway toward rigidity phenomena in higher-dimensional sub-Riemannian geometries with potential applications in geometric measure theory on Carnot groups.
Abstract
This paper examines minimal hypersurfaces in sub-Riemannian Heisenberg groups. We extend the celebrated Simons formula and Kato inequality to the sub-Riemannian setting, and we apply them to obtain integral curvature estimates for stable hypersurfaces. These results lead to structural conditions that imply a Bernstein-type rigidity theorem for smooth, non-characteristic hypersurfaces in the second Heisenberg group.
