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Related papers: Hypersurfaces with central convex cross-sections

200 papers

We describe convex quadric surfaces in n dimensions and characterize them as convex surfaces with quadric sections by a continuous family of hyperplanes.

Metric Geometry · Mathematics 2010-08-02 V. Soltan

We lay the foundations of convex hypersurface theory in contact topology, extending the work of Giroux in dimension three. Specifically, we prove that any closed hypersurface in a contact manifold can be $C^0$-approximated by a convex one.…

Symplectic Geometry · Mathematics 2026-04-30 Joseph Breen , Austin Christian , Ko Honda , Yang Huang

We prove that, in Minkowski space, if a spacelike, $(n-1)$-convex hypersurface $M$ with constant $\sigma_{n-1}$ curvature has bounded principal curvatures, then $M$ is convex. Moreover, if $M$ is not strictly convex, after an…

Differential Geometry · Mathematics 2020-05-14 Changyu Ren , Zhizhang Wang , Ling Xiao

We show that any hyperplane section of a variety which is the inverse image of a smooth variety of dimension at least 2 by an endomorphism (wich is not an automorphism) of the projective space, is linearly complete. We stress the case of…

Algebraic Geometry · Mathematics 2015-06-26 Guillaume Jamet

We give a necessary condition on a geodesic in a Riemannian manifold that can run in some convex hypersurface. As a corollary we obtain peculiar properties that hold true for every convex set in any generic Riemannian manifold (M,g). For…

Differential Geometry · Mathematics 2022-01-13 Alexander Lytchak , Anton Petrunin

The authors study the geometry of lightlike hypersurfaces on a four-dimensional manifold $(M, c)$ endowed with a pseudoconformal structure $c = CO (2, 2)$. They prove that a lightlike hypersurface $V \subset (M, c)$ bears a foliation formed…

Differential Geometry · Mathematics 2007-05-23 Maks A. Akivis , Vladislav V. Goldberg

Classical Delaunay surfaces are highly symmetric constant mean curvature (CMC) submanifolds of space forms. We prove the existence of Delaunay-type hypersurfaces in a large class of compact manifolds, using the geometry of cohomogeneity one…

Differential Geometry · Mathematics 2016-08-01 Renato G. Bettiol , Paolo Piccione

We give a new proof of the classification of contact real hypersurfaces with constant mean curvature in the complex hyperbolic quadric ${Q^m}^* = SO_{m,2}^o/SO_mSO_2$, where $m\geq 3$. We show that a contact real hypersurface $M$ in…

Differential Geometry · Mathematics 2019-01-23 Sebastian Klein , Young Jin Suh

We classify all real hypersurfaces with constant principal curvatures in the complex hyperbolic plane.

Differential Geometry · Mathematics 2007-05-23 Jurgen Berndt , Jose Carlos Diaz-Ramos

Let $\phi:M\to\mathbb{S}^{n+1}\subset\mathbb{R}^{n+2}$ be an immersion of a complete $n$-dimensional oriented manifold. For any $v\in\mathbb{R}^{n+2}$, let us denote by $\ell_v:M\to\mathbb{R}$ the function given by $\ell_v(x)=\phi(x),v$ and…

Differential Geometry · Mathematics 2009-02-17 Luis J. Alias , Aldir Brasil , Oscar Perdomo

We find the first examples of real hypersurfaces with two nonconstant principal curvatures in complex projective and hyperbolic planes, and we classify them. It turns out that each such hypersurface is foliated by equidistant Lagrangian…

Differential Geometry · Mathematics 2013-10-02 J. Carlos Diaz-Ramos , Miguel Dominguez-Vazquez , Cristina Vidal-Castiñeira

This paper is concerned with the completeness (with respect to the centroaffine metric) of hyperbolic centroaffine hypersurfaces which are closed in the ambient vector space. We show that completeness holds under generic regularity…

Differential Geometry · Mathematics 2016-06-17 Vicente Cortés , Marc Nardmann , Stefan Suhr

For a smooth, closed and uniformly $h$-convex hypersurface $M$ in $\mathbb{H}^{n+1}$, the horospherical Gauss map $G: M \rightarrow \mathbb{S}^n$ is a diffeomorphism. We consider the problem of finding a smooth, closed and uniformly…

Analysis of PDEs · Mathematics 2023-02-21 Li Chen

We classify hypersurfaces of the Minkowski space $\L^{n+1}$ that carry a totally geodesic foliation with complete leaves of codimension one. We prove that such a hypersurface is ruled, or a partial tube over a curve or contains a two or…

Differential Geometry · Mathematics 2018-10-16 S. M. B. Kashani , M. J. Vanaei , S. M. Yaghoobi

In this work, we obtain an unexpected geometric characterization of sphericity of a real-analytic Levi-nondegenerate hypersurface $M\subset\mathbb C^{2}$. We prove that $M$ is spherical if and only if its Segre\,(-Webster) varieties satisfy…

Complex Variables · Mathematics 2016-06-28 Ilya Kossovskiy

Complete hypersurfaces of dimension at least 2 and multiplicity at least 4 have wild Cohen-Macaulay type.

Commutative Algebra · Mathematics 2011-03-10 Andrew Crabbe , Graham J. Leuschke

We study some sub-Riemannian objects (such as horizontal connectivity, horizontal connection, horizontal tangent plane, horizontal mean curvature) in hypersurfaces of sub-Riemannian manifolds. We prove that if a connected hypersurface in a…

Differential Geometry · Mathematics 2007-05-23 Kang-Hai Tan , Xiao-Ping Yang

In this paper, we have studied biharmonic hypersurfaces in space form $\bar{M}^{n+1}(c)$ with constant sectional curvature $c$. We have obtained that biharmonic hypersurfaces $M^{n}$ with at most three distinct principal curvatures in…

Differential Geometry · Mathematics 2014-12-18 Ram Shankar Gupta

Ballico proved that a smooth projective variety $X$ of degree $d$ over a finite field of $q$ elements admits a smooth hyperplane section if $q\geq d(d-1)^{\dim X}$. In this paper, we refine this criterion for higher codimensional linear…

Algebraic Geometry · Mathematics 2024-02-28 Shamil Asgarli , Lian Duan , Kuan-Wen Lai

In this paper we study the Gauss map of hypersurfaces with constant weighted mean curvature in the Gaussian space. We show that if the image of the Gauss map is in a closed hemisphere, then the hypersurface is a hyperplane or a generalized…

Differential Geometry · Mathematics 2024-01-24 Michael Gomez , Matheus Vieira