• 제목/요약/키워드: Real hypersurface

검색결과 87건 처리시간 0.022초

JACOBI OPERATORS ALONG THE STRUCTURE FLOW ON REAL HYPERSURFACES IN A NONFLAT COMPLEX SPACE FORM II

  • Ki, U-Hang;Kurihara, Hiroyuki
    • 대한수학회보
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    • 제48권6호
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    • pp.1315-1327
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    • 2011
  • Let M be a real hypersurface of a complex space form with almost contact metric structure (${\phi}$, ${\xi}$, ${\eta}$, g). In this paper, we study real hypersurfaces in a complex space form whose structure Jacobi operator $R_{\xi}=R({\cdot},\;{\xi}){\xi}$ is ${\xi}$-parallel. In particular, we prove that the condition ${\nabla}_{\xi}R_{\xi}=0$ characterizes the homogeneous real hypersurfaces of type A in a complex projective space or a complex hyperbolic space when $R_{\xi}{\phi}S=R_{\xi}S{\phi}$ holds on M, where S denotes the Ricci tensor of type (1,1) on M.

CHARACTERIZATIONS OF REAL HYPERSURFACES OF TYPE A IN A COMPLEX SPACE FORM USED BY THE ζ-PARALLEL STRUCTURE JACOBI OPERATOR

  • Kim, Nam-Gil;Ki, U-Hang;Kurihara, Hiroyuki
    • 호남수학학술지
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    • 제30권3호
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    • pp.535-550
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    • 2008
  • Let M be a real hypersurface of a complex space form with almost contact metric structure $({\phi},{\xi},{\eta},g)$. In this paper, we study real hypersurfaces in a complex space form whose structure Jacobi operator $R_{\xi}=R({\cdot},{\xi}){\xi}$ is ${\xi}$-parallel. In particular, we prove that the condition ${\nabla}_{\xi}R_{\xi}=0$ characterize the homogeneous real hypersurfaces of type A in a complex: projective space $P_n{\mathbb{C}}$ or a complex hyperbolic space $H_n{\mathbb{C}}$ when $g({\nabla}_{\xi}{\xi},{\nabla}_{\xi}{\xi})$ is constant and not equal to -c/24 on M, where c is a constant holomorphic sectional curvature of a complex space form.

REAL HYPERSURFACES IN COMPLEX SPACE FORMS WITH ε-PARALLEL RICCI TENSOR AND STRUCTURE JACOBI OPERATOR

  • Ki, U-Hang;Perez Juan De Dios;Santos Florentino G.;Suh Young-Jin
    • 대한수학회지
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    • 제44권2호
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    • pp.307-326
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    • 2007
  • We know that there are no real hypersurfaces with parallel Ricci tensor or parallel structure Jacobi operator in a nonflat complex space form (See [4], [6], [10] and [11]). In this paper we investigate real hypersurfaces M in a nonflat complex space form $M_n(c)$ under the condition that ${\nabla}_{\varepsilon}S=0\;and\;{\nabla}_{\varepsilon}R_{\varepsilon}=0,\;where\;S\;and\;R_{\varepsilon}$ respectively denote the Ricci tensor and the structure Jacobi operator of M in $M_n(c)$.

SEMI-SYMMETRIC STRUCTURE JACOBI OPERATOR FOR REAL HYPERSURFACES IN THE COMPLEX QUADRIC

  • Imsoon Jeong;Gyu Jong Kim;Changhwa Woo
    • 대한수학회보
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    • 제60권4호
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    • pp.849-861
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    • 2023
  • In this paper, we introduce the notion of semi-symmetric structure Jacobi operator for Hopf real hypersufaces in the complex quadric Qm = SOm+2/SOmSO2. Next we prove that there does not exist any Hopf real hypersurface in the complex quadric Qm = SOm+2/SOmSO2 with semi-symmetric structure Jacobi operator. As a corollary, we also get a non-existence property of Hopf real hypersurfaces in the complex quadric Qm with either symmetric (parallel), or recurrent structure Jacobi operator.

THE RIGIDITY FOR REAL HYPERSURFACES IN P3(ℂ)

  • LEE, SEONG-BAEK;KIM, NAM-GIL;HAN, SEUNG-GOOK;TAKAGI, RYOICHI
    • 호남수학학술지
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    • 제22권1호
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    • pp.99-106
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    • 2000
  • We prove that a certain class of real hypersurfaces in $P_3({\mathbb{C}})$ has the rigidity. Making use of this we classify all homogeneous real hypersurfaces in $P_3({\mathbb{C}})$.

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NOTE ON REAL HYPERSURFACES OF NONFLAT COMPLEX SPACE FORMS IN TERMS OF THE STRUCTURE JACOBI OPERATOR AND RICCI TENSOR

  • KIM, NAM-GIL;LI, CHUNJI;KI, U-HANG
    • 호남수학학술지
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    • 제27권3호
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    • pp.487-504
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    • 2005
  • Let M be a real hypersurface with almost contact metric structure (${\phi}$, ${\xi}$, ${\eta}$, g) in a nonflat complex space form $M_n(c)$. We denote by A and S be the shape operator and the Ricci tensor of M respectively. In the present paper we investigate real hypersurfaces with $g(SA{\xi},\;A{\xi})=const$. of $M_n(c)$ whose structure Jacobi operator $R_{\xi}$ commute with both ${\phi}$ and S. We give a characterization of Hopf hypersurfaces of $M_n(c)$.

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