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 共查询到19条相似文献,搜索用时 125 毫秒
1.
王红 《数学研究》1998,31(1):34-39
对于三维Minkowski空间中的混合型时空曲面,证明了其在类空部分和类时部分上分别存在光滑的,并且连续到交界线上的等温参数.进一步,给出了混合型时空曲面存在在其类空部分和类时部分上是光滑的,而在交界线上是连续的等温参数的—个必要条件.  相似文献   

2.
刘会立 《数学学报》1995,38(2):191-199
本文给出了三维Minkowski空间中一般类空曲面与类时曲面的广义Weier-strass表示公式.  相似文献   

3.
关于3维Minkowski空间中类空曲面的若干结果   总被引:2,自引:0,他引:2  
陈维桓 《数学学报》1994,37(3):309-316
在本文,我们证明2维黎曼流形能实现为L3中的类空极大曲面的充要条件是相应的Ricci条件成立,此外还确定了L3中其平均曲率向量h满足条件△h=λh(λ∈R)的类空曲面  相似文献   

4.
研究了三维Minkowski空间中满足ΔG=φ(G+C)条件的类空轴旋转曲面,并给出了该类曲面的分类.主要结论为上述条件中当C为零向量时该曲面拥有常值平均曲率;当C为非零向量时,该曲面或是一类圆锥面、或是二类圆锥面.  相似文献   

5.
Cuong在文献中引入了四维Minkowski空间中类空曲面的LSr高斯映射的概念并研究了该空间中全脐类空曲面的微分几何性质.发现该类高斯映射存在奇异性并利用Lagrangian奇点理论和切触理论具体刻画了LSr值高斯映射的奇点.  相似文献   

6.
从法向量的角度研究n维Minkowski空间Rn(n≥4)中具有零平均曲率的类空曲面,并且证明了一个Bernstein型的定理.我们推广了Estudillo和Romero的结果,完全解决了Rn中有关浸入平稳曲面的Bernstein型问题.  相似文献   

7.
徐森林  寿乐丽 《应用数学》2004,17(2):289-294
In this paper, we study the relations between a compact spacelike hypersurface with hy-perplanar boundary in the (n 1)- dimensional Minkowski space-time L^n 1 being totally umbilicaland its hyperplanar boundary in a fixed hyperplane π of L^(n 1) being totally umbilical under certainconditions. We give the sufficient conditions for such hypersurface and its hyperplanar boundary tobe totally umbilical in their respective ambients.  相似文献   

8.
研究了由三维Minkowski空间$E^3_1$中一个类空曲面$S_1$上一个单参数测地曲线族的切线所构成的直线汇$T$,它以$S_1$为一个焦曲面.证明了$T$的两个可展曲面族沿着第二个焦曲面$S_2$的正交曲线网相交的充要条件是$S_1$是可展曲面.对于$T$的两个焦曲面$S_1$和$S_2$之间沿着同一光线的对应,还证明了其保持渐近曲线网的充要条件.最后,研究了$T$的正交曲面$S$,并且证明了如果$S$是$E^3_1$中的一个极大曲面,那么,$T$的焦曲面$S_1$和$S_2$之间沿着同一光线的对  相似文献   

9.
In this paper we study translation surfaces of some new types in 3-Minkowski space E13 and give some classifications of such surfaces whose mean curvature and Gauss curvature satisfy certain conditions.  相似文献   

10.
左达峰  陈卿  程艺 《数学年刊A辑》2002,23(3):331-338
利用可积系统的思想,借助三维Minkowski空间L3的矩阵模型,研究了L3中具有调和逆平均曲率的类空曲面和洛伦兹调和逆平均曲率类时曲面的可积性及其形变.  相似文献   

11.
In this paper, we analyze the problem of constructing a surface pencil from a given spacelie (timelike) line of curvature. Using the Frenet frame of the given line of curvature in Minkowski 3-space, we express the surface pencil as a linear combination of this frame and derive the necessary and sufficient conditions for the coefficients to satisfy the line of curvature requirement. We illustrate this method by presenting some examples.  相似文献   

12.
We find all space-like loxodromes on rotational surfaces which have space-like meridians or time-like meridians, respectively by using a relevant Lorentzian angle in Minkowski 3-space. To understand loxodromes better, we draw some pictures of them via Mathematica computer program.  相似文献   

13.
In this paper, we construct helicoidal surfaces under the cubic screw motion with prescribed mean or Gauss curvature in Minkowski 3-space . We also find explicitly the relation between the mean curvature and Gauss curvature of them. Furthermore, we discuss helicoidal surfaces under the cubic screw motion with H2=K and prove that these surfaces have equal constant principal curvatures.  相似文献   

14.
Let be a Minkowski 3-space of Randers type with , where is the Euclidean metric and . We consider minimal surfaces in and prove that if a connected surface M in is minimal with respect to both the Busemann–Hausdorff volume form and the Holmes–Thompson volume form, then up to a parallel translation of , M is either a piece of plane or a piece of helicoid which is generated by lines screwing about the x 3-axis.   相似文献   

15.
A spacelike surface in a Lorentzian manifold whose mean curvature vector is lightlike everywhere is called marginally trapped. The classification of marginally trapped surfaces in Minkowski 4-space which are invariant under a subgroup of the Lorentz group that leaves invariant a lightlike direction, i.e. the so-called screw invariant surfaces, is obtained. As corollaries, the screw invariant marginally trapped surfaces with harmonic mean curvature vector and with prescribed Gaussian curvature are explicitly described.  相似文献   

16.
We describe a robust method for constructing a tubular surface surrounding a spacelike curve with a spacelike principal normal in Minkowski 3-Space. Our method is designed to eliminate undesirable twists and wrinkles in the tubular surface’s skin at points where the curve experiences high torsion. In our construction the tubular surface’s twist is bounded by the spacelike curve’s curvature and is independent of the spacelike curve’s torsion.   相似文献   

17.
In this paper, position vector of a time-like slant helix with respect to standard frame of Minkowski space E31 is studied in terms of Frenet equations. First, a vector differential equation of third order is constructed to determine position vector of an arbitrary time-like slant helix. In terms of solution, we determine the parametric representation of the slant helices from the intrinsic equations. Thereafter, we apply this method to find the representation of a time-like Salkowski and time-like anti-Salkowski curves as examples of a slant helices, by means of intrinsic equations. Moreover, we present some new characterizations of slant helices and illustrate some examples of our main results.  相似文献   

18.
We deal with solitons of the mean curvature flow. The definition of translating solitons on a light-like direction in Minkowski 3-space is introduced. Firstly, we classify those which are graphical, translation surfaces, obtaining space-like and time-like, entire and not entire, complete and incomplete examples. Among them, all our time-like examples are incomplete. The second family consists of those which are invariant by a 1-dimensional subgroup of parabolic motions, i.e., with light-like axis. The classification result implies that all examples of this second family have singularities.  相似文献   

19.
It is proved that, in Minkowski 3-space, a CSM-helicoidal surface, i.e., a helicoidal surface under cubic screw motion is isometric to a rotation surface so that helices on the helicoidal surface correspond to parallel circles on the rotation surface. By distinguishing a CSM-helicoidal surface as three cases, that is, the case of type I, the case of type II with negative and positive pitch, the relations are discussed between the mean curvatures or Gauss maps of a pair of isometric helicoidal and rotation surface. A CSM-helicoidal surface of Case 1 or 2 and its isometric rotation surface with null axis have same mean curvatures (resp. Gauss maps) if and only if they are minimal. But each pair of isometric CSM-helicoidal surface of Case 3 and rotation surface with spacelike axis have different Gauss maps.  相似文献   

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