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1.
We announce the following result: every maximal globally hyperbolic 3-dimensional spacetime with compact Cauchy surface, and with nonpositive constant curvature admits a unique time function whose fibers are constant mean curvature surfaces. We discuss the extension of this result in higher dimensions. To cite this article: T. Barbot et al., C. R. Acad. Sci. Paris, Ser. I 336 (2003).  相似文献   

2.
We study immersed prescribed mean curvature compact hypersurfaces with boundary in Hn+1(-1). When the boundary is a convex planar smooth manifold with all principal curvatures greater than 1, we solve a nonparametric Dirichlet problem and use this, together with a general flux formula, to prove a parametric uniqueness result, in the class of all immersed compact hypersurfaces with the same boundary. We specialize this result to a constant mean curvature, obtaining a characterization of totally umbilic hypersurface caps.  相似文献   

3.
Several uniqueness results for the spacelike slices in certain Robertson–Walker spacetimes are proved under boundedness assumptions either on the mean curvature function of the spacelike surface or on the restriction of the time coordinate on the surface when the mean curvature is a constant. In the nonparametric case, a uniqueness result and a nonexistence one are proved for bounded entire solutions of some constant mean curvature spacelike differential equations.  相似文献   

4.
Lorentz空间中常平均曲率类空超曲面   总被引:1,自引:0,他引:1  
张远征 《数学学报》2002,45(3):571-574
本文证明了n+1维Lorentz空Ln+1中以Sn-1(r)为边界的紧致常平均曲率类空超曲面只有 Bn(r)和超伪球面盖.对于 Rn+1中的紧致常平均曲率超曲面,当高斯映照像落在一个半球面内时,得到相应的唯一性结果.  相似文献   

5.
We give an existence result for constant mean curvature graphs in hyperbolic space . Let be a compact domain of a horosphere in whose boundary is mean convex, that is, its mean curvature (as a submanifold of the horosphere) is positive with respect to the inner orientation. If H is a number such that , then there exists a graph over with constant mean curvature H and boundary . Umbilical examples, when is a sphere, show that our hypothesis on H is the best possible. Received July 18, 1997 / Accepted April 24, 1998  相似文献   

6.
In this article we extend a well known theorem of J. Serrin about existence and uniqueness of graphs of constant mean curvature in Euclidean space to a broad class of Riemannian manifolds. Our result also generalizes several others proved recently and includes the new case of Euclidean “rotational” graphs with constant mean curvature.  相似文献   

7.
Abstract

A classical result of Wente, motivated by the study of sessile capillarity droplets, demonstrates the axial symmetry of every hypersurface which meets a hyperplane at a constant angle and has mean curvature dependent only on the distance from that hyperplane. An analogous result is proven here for the fractional mean curvature operator.  相似文献   

8.
In this paper, we give a height estimate for constant mean curvature graphs. Using this result we prove two uniqueness results for the Dirichlet problem associated to the constant mean curvature equation on unbounded domains.  相似文献   

9.
胡和生 《数学学报》1956,6(1):127-137
<正> §1.如所知,二維黎曼測度ds~2=E(u,ν)du~2+2F(u,ν)du dν+G(u,ν)dν~2;在E_3中的實現不是唯一的,而容有與單項目的兩個任意函數有關的連继變形.如此,曲面的測度不能決定曲面,但不同於此,m維黎曼測度(m≥3)如能在E_(m+1)中實現,一般地說實現它的超曲面只能是唯一的,也就是說,超曲面V_m E_(m+1)一般是不能變形的,而能變形的只是狹窄的一類超曲面.  相似文献   

10.
本文估计了空间形式Nn+1(c)中常平均曲率超曲面上共形度量的曲率上界,并用其研究了Nn+1(c)中常平均曲率超曲面的强稳定性.  相似文献   

11.
张士诚 《数学杂志》2014,34(4):804-808
本文研究了单位球中的数量曲率满足r=aH+b的完备超曲面的问题.利用极值原理的方法,获得了超曲面的一个刚性结果,推广了这一类具有常中曲率或者常数量曲率超曲面的结果.  相似文献   

12.
The distance of an almost‐constant mean curvature boundary from a finite family of disjoint tangent balls with equal radii is quantitatively controlled in terms of the oscillation of the scalar mean curvature. This result allows one to quantitatively describe the geometry of volume‐constrained stationary sets in capillarity problems.© 2017 Wiley Periodicals, Inc.  相似文献   

13.
We prove the existence of embedded spheres with large constant mean curvature in any compact Riemannian manifold (M, g). This result partially generalizes a result of R. Ye which handles the case where the scalar curvature function of the ambient manifold (M, g) has non-degenerate critical points.  相似文献   

14.
ON COMPLETE SPACE-LIKE SUBMANIFOLDS WITH PARALLEL MEAN CURVATURE VECTOR   总被引:4,自引:0,他引:4  
§1.IntroductionLetNn+ppbean(n+p)-dimensionalconnectedpseudo-Riemannianmanifoldofindexp.IfNn+ppiscompleteandhasconstantsection...  相似文献   

15.
王一令 《数学学报》2002,45(4):719-730
本文把Berard P.,do Carmo M.,Santos W.在1998年所得的结果,分别推广到局部对称的Cartan-Hadamard流形中具有常平均曲率和有限全曲率的完备超曲面,以及球面上具有平行平均曲率和有限全曲率的完备子流形.  相似文献   

16.
In this paper, we study affine non-degenerate Blaschke immersions from a surface M in 3. We will assume that M has constant affine curvature and constant affine mean curvature, i.e. both the determinant and the trace of the shape operator are constant. Clearly, affine spheres satisfy both these conditions. In this paper, we completely classify the affine surfaces with constant affine curvature and constant affine mean curvature, which are not affine spheres.Research Assistant of the National Fund for Scientific Research (Belgium).  相似文献   

17.
We study under what condition a constant mean curvature surface can be round: i) If the boundary of a compact immersed disk type constant mean curvature surface in consists of lines of curvature and has less than 4 vertices with angle , then the surface is spherical; ii) A compact immersed disk type capillary surface with less than 4 vertices in a domain of bounded by spheres or planes is spherical; iii) The mean curvature vector of a compact embedded capillary hypersurface of with smooth boundary in an unbounded polyhedral domain with unbalanced boundary should point inward; iv) If the kth order () mean curvature of a compact immersed constant mean curvature hypersurface of without boundary is constant, then the hypersurface is a sphere. Received: 3 October 2000 / Published online: 1 February 2002  相似文献   

18.
In this paper, we give general curvature estimates for constant mean curvature surfaces immersed into a simply-connected 3-dimensional space form. We obtain bounds on the norm of the traceless second fundamental form and on the Gaussian curvature at the center of a relatively compact stable geodesic ball (and, more generally, of a relatively compact geodesic ball with stability operator bounded from below). As a by-product, we show that the notions of weak and strong Morse indices coincide for complete non-compact constant mean curvature surfaces. We also derive a geometric proof of the fact that a complete stable surface with constant mean curvature 1 in the usual hyperbolic space must be a horosphere.  相似文献   

19.
We study several aspects of the geometry of conformally stationary Lorentz manifolds, and particularly of GRW spaces, due to the presence of a closed conformal vector field. More precisely, we begin by extending a result of J. Simons on the minimality of cones in Euclidean space to these spaces, and apply it to the construction of complete, noncompact minimal Lorentz submanifolds of both de Sitter and anti-de Sitter spaces. Then we state and prove very general Bernstein-type theorems for spacelike hypersurfaces in conformally stationary Lorentz manifolds, one of which not assuming the hypersurface to be of constant mean curvature. Finally, we study the strong r-stability of spacelike hypersurfaces of constant r-th mean curvature in a conformally stationary Lorentz manifold of constant sectional curvature, extending previous results in the current literature.  相似文献   

20.
In this paper we derive a sharp estimate for the supremum of the scalar curvature (or, equivalently, the infimum of the squared norm of the second fundamental form) of a constant mean curvature hypersurface with two principal curvatures immersed into a Riemannian space form of constant curvature. Our results will be an application of the generalized Omori-Yau maximum principle, following the approach by Pigola et al. (Memoirs Am Math Soc 822, 2005).  相似文献   

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