Closed Biconservative Hypersurfaces in Spheres
Stefano Montaldo, Cezar Oniciuc, Alvaro Pampano
TL;DR
The paper addresses the existence and structure of non-CMC biconservative rotational hypersurfaces in space forms, focusing on compact examples in spheres. It proves that their profile curves are $p$-elastic with $p=\frac{n-2}{n+1}$ and develops a variational framework around $\mathbf{\Theta}_p(\gamma)=\int \kappa^p ds$. Using the Euler–Lagrange equation and a closure analysis, the authors establish a discrete biparametric family of closed, non-CMC rotational biconservative hypersurfaces in $\mathbb{S}^n(\rho)$ for every $n\ge3$, none embedding. The results generalize known 3D classifications to arbitrary dimension and provide explicit closure criteria via the phase-integral $I(d)$.
Abstract
We characterise the profile curves of non-CMC biconservative rotational hypersurfaces of space forms $N^n(ρ)$ as $p$-elastic curves, for a suitable rational number $p\in[1/4,1)$ which depends on the dimension $n$ of the ambient space. Analysing the closure conditions of these $p$-elastic curves, we prove the existence of a discrete biparametric family of non-CMC closed (i.e., compact without boundary) biconservative hypersurfaces in $\mathbb{S}^n(ρ)$. None of these hypersurfaces can be embedded in $\mathbb{S}^n(ρ)$.
