Structure Jacobi Operators of Semi-invarinat Submanifolds in a Complex Space Form II
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Let $M$ be a semi-invariant submanifold of codimension 3 with almost contact metric structure$(\phi, \xi, \eta, g)$ in a complex space form $M_{n+1} (c)$. We denote by $R_\xi$ the structureJacobi operator with respect to the structure vector field $\xi$ and by $\bar{r}$ the scalar curvature of $M$. Suppose that $R_\xi$ is $\phi\nabla_\xi \xi$-parallel and at the same time the third fundamental form$t$ satisfies $dt(X,Y)=2\theta g(\phi X,Y)$ for a scalar $\theta(\neq2c)$ and any vector fields$X$ and $Y$ on $M$. In this paper, we prove that if it satisfies $R_\xi \phi=\phi R_\xi$, then $M$ is a Hopf hypersurfaceof type (A) in $M_{n+1} (c)$ provided that $\bar{r}-2(n-1)c\leq0$.
Abstract
Let $M$ be a semi-invariant submanifold of codimension 3 with almost contact metric structure$(\phi, \xi, \eta, g)$ in a complex space form $M_{n+1} (c)$. We denote by $R_\xi$ the structureJacobi operator with respect to the structure vector field $\xi$ and by $\bar{r}$ the scalar curvature of $M$. Suppose that $R_\xi$ is $\phi\nabla_\xi \xi$-parallel and at the same time the third fundamental form$t$ satisfies $dt(X,Y)=2\theta g(\phi X,Y)$ for a scalar $\theta(\neq2c)$ and any vector fields$X$ and $Y$ on $M$. In this paper, we prove that if it satisfies $R_\xi \phi=\phi R_\xi$, then $M$ is a Hopf hypersurfaceof type (A) in $M_{n+1} (c)$ provided that $\bar{r}-2(n-1)c\leq0$.
참고문헌 (35)
- A. Bejancu, "CR-submanifolds of a Kahler manifold I", Proc. Amer. Math. Soc, 69, pp.135~142 (1978)
- J. Berndt, "Real hypersurfaces with constant principal curvatures in a complex hyperbolic space", J. Reine Angew. Math, 395, pp.132~141 (1989)
- J. Berndt, "Cohomogeneity one actions on non compact symmetric spaces of rank one", Trans. Amer. Math. Soc, 359, pp.3425~3438 (2007)
- D. E. Blair, "Semi-invariant immersions", Kodai Math. Sem. Rep, 27, pp.313~319 (1976)
- T. E. Cecil, "Focal sets and real hypersurfaces in complex projective space", Trans. Amer. Math. Soc, 269, pp.481~499 (1982)
- J. T. Cho, "Real hypersurfaces of a complex projective space in terms of the Jacobi operators", Acta Math. Hungar, 80, pp.155~167 (1998)
- J. T. Cho, "Real hypersurfaces in complex space forms with Reeb flow symmetric Jacobi operator", Canadian Math. Bull, 51, pp.359~371 (2008)
- J. Erbacher, "Reduction of the codimension of an isometric immersion", J. Diff. Geom, 3, pp.333~340 (1971)
- 허종임, "Semi-invariant submanifolds of codimension 3 of a complex projective space in terms of the Jacobi operator", 대한수학회보, 42(1), pp.93~119 (2005), 대한수학회
- S. Kawamoto, "Codimension reduction for real submanifolds of a complex hyperbolic space", Rev. math. univ. comput. madrid, 7, pp.119~128 (1994)
- U-H. Ki, "Cyclic-parallel real hypersurfaces of a complex space form", Tsukuba J. Math, 12, pp.259~268 (1988)
- U-H. Ki, "Commuting Jacobi operators for a semi-invariant submanifold of codimension 3 in complex space forms", J. Nat. Acad. Sci. ROK, Sci. Ser, 58(2), pp.271~306 (2019)
- Ki, U-H, "The Ricci tensor and structure Jacobi operator of submanifolds of codimension 3 in complex space forms", J. Nat. Acad. Sci. ROK, Sci. Ser, 59(2), pp.367~394 (2020)
- Ki, U-H., "Jacobi operators along the structure flow on semi-invariant subminifolds of codimension 3 in a complex space form", J. Nat. Acad. Sci. ROK. Sci. Ser, 59(1), pp.19~44 (2020)
- 기우항, "Structure Jacobi Operator of Semi-invarinat Submanifolds in Complex Space Forms", East Asian Mathematical Journal, 36(3), pp.389~415 (2020), 영남수학회
- Hiroyuki Kurihara, "Jacobi operators with respect to the Reeb vector fields on real hypersurfaces in a nonflat complex space form", Kyungpook Mathematical Journal, 56(2), pp.541~575 (2016), 경북대학교 자연과학대학 수학과
- U-Hang Ki, "Semi-invariant submanifolds of codimension 3 in a complex space form in terms of the structure Jacobi operator", 대한수학회논문집, 37(1), pp.229~257 (2022), 대한수학회[DOI]
- U-H. Ki, "The structure vector filed and structure Jacobi operator of real hypersurfaces in nonflat complex space forms", Geom. Dedicata, 149, pp.161~176 (2010)
- U-H. Ki, "Jacobi operators on a semi-invariant submanifolds of codimension 3 in a complex projective space", Nihonkai Math J, 14, pp.1~16 (2003)
- U-H. Ki, "Submanifold of codimension 3 with almost contact metric structure in a complex space form", J. Nat. Acad. Sci. ROK. Sci. Ser, 58(1), pp.37~63 (2019)
- U-H. Ki, "Semi-invariant submanifolds of condimension 3 in a complex space form with commuting structure Jacobi operator", Kyungpook. Math. J
- U-H. Ki, "Submanifolds of codimension 3 admitting almost contact metric structure in a complex projective space", Nihonkai Math J, 11, pp.57~86 (2000)
- M. Kimura, "Real hypersurfaces and complex submanifolds in complex projective space", Trans. Amer. Math. Soc, 296, pp.137~149 (1986)
- S. Montiel, "On some real hypersurfaces of a complex hyperbolic space", Geom. Dedicata, 20, pp.245~261 (1986)
- R. Niebergall, "Tight and Taut submanifolds", pp.233~305 (1998), Cambridge University Press
- M. Okumura, "On some real hypersurfaces of a complex projective space", Trans. Amer. Math. Soc, 212, pp.355~364 (1973)
- M. Okumura, "Normal curvature and real submanifold of the complex projective space", Geom. Dedicata, 7, pp.509~517 (1978)
- M. Okumura, "Codimension reduction problem for real submanifolds of complex projective space", Colloq. Math Jańos Bolyai, 56, pp.574~585 (1989)
- M. Ortega, "Non-existence of real hypersurface with parallel structure Jacobi operator in nonflat complex space forms", Rocky Mountain J. Math, 36, pp.1603~1613 (2006)
- H. Song, "Some differential-geometric properties of R-spaces", Tsukuba J. Math, 25, pp.279~298 (2001)
- R. Takagi, "On homogeneous real hypersurfaces in a complex projective space", Osaka J. Math, 19, pp.495~506 (1973)
- R. Takagi, "Real hypersurfaces in a complex projective space with constant principal curvatures I,II", J. Math. Soc. Japan, 27, pp.43~53 (1975)
- Y. Tashiro, "Relations between the theory of almost complex spaces and that of almost contact spaces", Sugaku, 16, pp.34~61 (1964)
- K. Yano, "On (f, g, u, v, w, λ, µ, ν)-structure satisfying λ2 + µ2 + ν2 = 1", Kodai Math. Sem. Rep, 29, pp.285~307 (1978)
- K. Yano, "CR submanifolds of Kaehlerian and Sasakian manifolds" (1983), Birkhauser
