• Title/Summary/Keyword: Gauss curvature

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ANOTHER CHARACTERIZATION OF ROUND SPHERES

  • Lee, Seung-Won;Koh, Sung-Eun
    • Bulletin of the Korean Mathematical Society
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    • v.36 no.4
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    • pp.701-706
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    • 1999
  • A characterization of geodesic spheres in the simply connected space forms in terms of the ratio of the Gauss-Kronecker curvature and the (usual) mean curvature is given: An immersion of n dimensional compact oriented manifold without boundary into the n + 1 dimensional Euclidean space, hyperbolic space or open half sphere is a totally umbilicimmersion if the mean curvature $H_1$ does not vanish and the ratio $H_n$/$H_1$ of the Gauss-Kronecker curvature $H_n$ and $H_1$ is constant.

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CLASSIFICATIONS OF ROTATION SURFACES IN PSEUDO-EUCLIDEAN SPACE

  • Kim, Young-Ho;Yoon, Dae-Won
    • Journal of the Korean Mathematical Society
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    • v.41 no.2
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    • pp.379-396
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    • 2004
  • In this article, we study rotation surfaces in the 4-dimensional pseudo-Euclidean space E$_2$$^4$. Also, we obtain the complete classification theorems for the flat rotation surfaces with finite type Gauss map, pointwise 1-type Gauss map and an equation in terms of the mean curvature vector. In fact, we characterize the flat rotation surfaces of finite type immersion with the Gauss map and the mean curvature vector field, namely the Gauss map of finite type, pointwise 1-type Gauss map and some algebraic equations in terms of the Gauss map and the mean curvature vector field related to the Laplacian of the surfaces with respect to the induced metric.

CHENG -YAU OPERATOR AND GAUSS MAP OF TRANSLATION SURFACES

  • Kim, Dong Seo;Kim, Dong-Soo
    • The Pure and Applied Mathematics
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    • v.28 no.1
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    • pp.43-53
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    • 2021
  • We study translation surfaces in the Euclidean 3-space ��3 and the Gauss map N with respect to the so-called Cheng-Yau operator ☐. As a result, we prove that the only translation surfaces with Gauss map N satisfying ☐N = AN for some 3 × 3 matrix A are the flat ones. We also show that the only translation surfaces with Gauss map N satisfying ☐N = AN for some nonzero 3 × 3 matrix A are the cylindrical surfaces.

MAXIMAL SPACE-LIKE HYPERSURFACES IN H14(-1) WITH ZERO GAUSS-KRONECKER CURVATURE

  • CHENG QING-MING;SUH YOUNG JIN
    • Journal of the Korean Mathematical Society
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    • v.43 no.1
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    • pp.147-157
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    • 2006
  • In this paper, we study complete maximal space-like hypersurfaces with constant Gauss-Kronecker curvature in an antide Sitter space $H_1^4(-1)$. It is proved that complete maximal spacelike hypersurfaces with constant Gauss-Kronecker curvature in an anti-de Sitter space $H_1^4(-1)$ are isometric to the hyperbolic cylinder $H^2(c1){\times}H^1(c2)$ with S = 3 or they satisfy $S{\leq}2$, where S denotes the squared norm of the second fundamental form.

ON A GENERALIZATION OF FENCHEL`S THEOREM

  • Chai, Y.D.;Kim, Moon-Jeong
    • Communications of the Korean Mathematical Society
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    • v.15 no.1
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    • pp.103-109
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    • 2000
  • In this paper, we present the proof of generalized Fenchel's theorem by estimating the Gauss-Kronecker curvature of the tube of a nondegenerate closed curve in R$^{n}$ .

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TRANSLATION AND HOMOTHETICAL SURFACES IN EUCLIDEAN SPACE WITH CONSTANT CURVATURE

  • Lopez, Rafael;Moruz, Marilena
    • Journal of the Korean Mathematical Society
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    • v.52 no.3
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    • pp.523-535
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    • 2015
  • We study surfaces in Euclidean space which are obtained as the sum of two curves or that are graphs of the product of two functions. We consider the problem of finding all these surfaces with constant Gauss curvature. We extend the results to non-degenerate surfaces in Lorentz-Minkowski space.

SURFACES IN $\mathbb{E}^3$ WITH L1-POINTWISE 1-TYPE GAUSS MAP

  • Kim, Young Ho;Turgay, Nurettin Cenk
    • Bulletin of the Korean Mathematical Society
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    • v.50 no.3
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    • pp.935-949
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    • 2013
  • In this paper, we study surfaces in $\mathb{E}^3$ whose Gauss map G satisfies the equation ${\Box}G=f(G+C)$ for a smooth function $f$ and a constant vector C, where ${\Box}$ stands for the Cheng-Yau operator. We focus on surfaces with constant Gaussian curvature, constant mean curvature and constant principal curvature with such a property. We obtain some classification and characterization theorems for these kinds of surfaces. Finally, we give a characterization of surfaces whose Gauss map G satisfies the equation ${\Box}G={\lambda}(G+C)$ for a constant ${\lambda}$ and a constant vector C.