arXiv research

Minimal hypersurfaces in spheres generated by isoparametric foliations are found.

This paper gives a survey of recent progress in isoparametric functions and isoparametric hypersurfaces, mainly in two directions. (1) Isoparametric functions on Riemannian manifolds, including exotic spheres. The existences and non-existences will be considered. (2) The Yau conjecture on the first eigenvalues of the e…

In a previous work, we studied isoparametric functions on Riemannian manifolds, especially on exotic spheres. One result there says that, in the family of isoparametric hypersurfaces of a closed Riemannian manifold, there exist at least one minimal isoparametric hypersurface. In this note, we show such minimal isoparam…

The image of the Gauss map of any oriented isoparametric hypersurface of the unit standard sphere $S^{n+1}(1)$ is a minimal Lagrangian submanifold in the complex hyperquadric $Q_n({\mathbf C})$. In this paper we show that the Gauss image of a compact oriented isoparametric hypersurface with $g$ distinct constant princi…

In this paper, we study isoparametric hypersurfaces in Finsler space forms by investigating focal points, tubes and parallel hypersurfaces of submanifolds. We prove that the focal submanifolds of isoparametric hypersurfaces are anisotropic-minimal and obtain the Cartan-type formula in a Finsler space form with vanishin…

Classifies hypersurfaces with constant isotropic curvature in space forms.

In this paper, two sequences of minimal isoparametric hypersurfaces are constructed via representations of Clifford algebras. Based on these, we give estimates on eigenvalues of the Laplacian of the focal submanifolds of isoparametric hypersurfaces in unit spheres. This improves results of [TY13] and [TXY14]. Eells and…

Minimal hypersurfaces in real projective spaces have at least n+2 Morse index.

Associated with isoparametric foliations of unit spheres, there are two classes of minimal surfaces $-$ minimal isoparametric hypersurfaces and focal submanifolds. By virtue of their rich structures, we find new series of minimizing cones. They are cones over focal submanifolds and cones over suitable products among th…

The paper proves conditions for closed minimally immersed hypersurfaces in a 5-sphere.

Paper proves rigidity of certain minimal hypersurfaces in a 5D sphere.

The study characterizes hypersurfaces in spheres with constant scalar curvature.

Paper finds conditions for minimal hypersurfaces in S^6 with constant scalar curvature.

We find many examples of compact Riemannian manifolds $(M,g)$ whose closed minimal hypersurfaces satisfy a lower bound on their index that is linear in their first Betti number. Moreover, we show that these bounds remain valid when the metric $g$ is replaced with $g'$ in a neighbourhood of $g$. Our examples $(M,g)$ con…

Extends isoparametric foliations and area-minimizing cones in product manifolds.

The paper classifies isoparametric hypersurfaces in conic Finsler spaces.

The paper studies inverse mean curvature flow on hypersurfaces in space forms.

Ancient solutions found for mean curvature flow of isoparametric submanifolds.

The paper classifies PMCV hypersurfaces in non-flat pseudo-Riemannian space forms.

A well known conjecture of Yau states that the first eigenvalue of every closed minimal hypersurface $M^n$ in the unit sphere $S^{n+1}(1)$ is just its dimension $n$. The present paper shows that Yau conjecture is true for minimal isoparametric hypersurfaces. Moreover, the more fascinating result of this paper is that t…

Paper classifies hypersurfaces in a sphere with specific curvature properties.

The paper proves properties of specific hypersurfaces in a 5-sphere.

Navigation in Lorentz Finsler geometry induces isoparametric hypersurfaces.

In this note, we give a classification of complete anisotropic isoparametric hypersurfaces, i.e., hypersurfaces with constant anisotropic principal curvatures, in Euclidean spaces, which is in analogue with the classical case for isoparametric hypersurfaces in Euclidean spaces. On the other hand, by an example of local…

New findings on Chern's conjecture for Dupin hypersurfaces.

The paper proves conditions for a 4D minimal surface to be isoparametric.

Study on isoparametric and constant-curvature hypersurfaces in Finsler spaces.

Classifies isoparametric hypersurfaces in 3D manifolds.

In this paper, we introduce and study the locally strongly convex equiaffine isoparametric hypersurfaces and equiaffine isoparametric functions on the affine space $A^{n+1}$. Motivated by the case on the Euclidean space $E^{n+1}$, we first introduce the concept of equiaffine parallel hypersurfaces in $A^{n+1}$, obtaini…

The $n$-dimensional complex hyperquadric is a compact complex algebraic hypersurface defined by the quadratic equation in the $(n+1)$-dimensional complex projective space, which is isometric to the real Grassmann manifold of oriented 2- planes and is a compact Hermitian symmetric space of rank 2. In this paper we study…

In this paper, we discuss anisotropic submanifolds and isoparametric hypersurfaces in a Randers space form (N,F) with the navigation datum (h,W). We find that (N, F) with respect to the BH-volume and (N,h) have the same isoparametric hypersurfaces although, in general, their isoparametric functions are different. This …

The study classifies isoparametric and homogeneous hypersurfaces in product spaces.

The paper classifies and explores isoparametric hypersurfaces in pseudo-Riemannian space forms.

Survey of Cartan's work on isoparametric hypersurfaces in spheres.

New isoparametric hypersurfaces found in Damek-Ricci spaces.

In this paper, we introduce isoparametric functions and isoparametric hypersurfaces in Finsler manifolds and give the necessary and sufficient conditions for a transnormal function to be isoparametric. We then prove that hyperplanes, Minkowski hyperspheres and $F^*$-Minkowski cylinders in a Minkowski space with $BH$-vo…

Surveying isoparametric hypersurfaces in spheres, focusing on Élie Cartan's techniques.

Survey of Cartan and Münzner's work on isoparametric hypersurfaces.

The paper classifies isoparametric hypersurfaces in product spaces with different curvatures.

In this note, we study properties of the gradient map of the isoparametric polynomial. For a given isoparametric hypersurface in sphere, we calculate explicitly the gradient map of its isoparametric polynomial which turns out many interesting phenomenons and applications. We find that it should map not only the focal s…

Tight isoparametric hypersurfaces in spheres have minimal critical points.

Let m>1 and n>1 be any pair of integers. In this paper we prove that if H is between the numbers \cot(\fracπ{m}) and b_{m,n}=\frac{(m^2-2)\sqrt{n-1}}{n\sqrt{m^2-1}}, then, there exists a non isoparametric, compact embedded hypersurface in S^{n+1} with constant mean curvature H that admits the group O(n)x Z_m in their g…

The study classifies isoparametric hypersurfaces in specific product spaces.

This note constructs complex structures on specific isoparametric hypersurfaces.

The paper proves isoparametric functions on Finsler space forms under specific conditions.

In this paper, we investigate the first eigenvalues of two closed eigenvalue problems of the bi-Beltrami-Laplacian on minimal embedded isoparametric hypersurface in the unit sphere $\mathbb{S}^{n+1}(1)$. Although many mathematicians want to derive the corresponding results for the first eigenvalues of bi-Beltrami-Lapla…

In this paper, I study the isoparametric hypersurfaces in a Randers sphere $(S^n,F)$ of constant flag curvature, with the navigation datum $(h,W)$. I prove that an isoparametric hypersurface $M$ for the standard round sphere $(S^n,h)$ which is tangent to $W$ remains isoparametric for $(S^n,F)$ after the navigation proc…

Revisits and applies a formula for hypersurface Euler characteristics.