A lower bound for $L_2$ length of second fundamental form on minimal hypersurfaces

Abstract

We prove a weak version of the Perdomo Conjecture, namely, there is a positive constant $\delta (n)>0$ depending only on $n$ such that on any closed embedded, non-totally geodesic, minimal hypersurface $M^n$ in ${\mathbb{S}}^{n+1}$, $${\int }_{M}S\ge \delta (n)\mathrm{Vol}(M^n),$$ where $S$ is the squared length of the second fundamental form of $M^n$. The Perdomo Conjecture asserts that $\delta (n)=n$ which is still open in general. As byproducts, we also obtain some integral inequalities and Simons-type pinching results on closed embedded (or immersed) minimal hypersurfaces, with the first positive eigenvalue ${\lambda }_1(M)$ of the Laplacian involved.

accepted by Proceedings of the American Mathematical Society