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CR-WARPED PRODUCT SUBMANIFOLDS OF NEARLY KAEHLER MANIFOLDS

  • Published : 2009.09.01

Abstract

As warped product manifolds provide an excellent setting to model space time near black holes or bodies with large gravitational field, the study of these manifolds assumes significance in general. B. Y. Chen [4] initiated the study of CR-warped product submanifolds in a Kaehler manifold. He obtained a characterization for a CR-submanifold to be locally a CR-warped product and an estimate for the squared norm of the second fundamental form of CR-warped products in a complex space form (cf [6]). In the present paper, we have obtained a necessary and sufficient conditions in terms of the canonical structures P and F on a CR-submanifold of a nearly Kaehler manifold under which the submanifold reduces to a locally CR-warped product submanifold. Moreover, an estimate for the second fundamental form of the submanifold in a generalized complex space is obtained and thus extend the results of Chen to a more general setting.

Keywords

References

  1. R. L. Bishop and B. O'Neill, Manifolds of negative curvature, Trans. Amer. Math. Soc. 145 (1969), 1.49 https://doi.org/10.1090/S0002-9947-1969-0251664-4
  2. B. Y. Chen, CR-submanifolds of a Kaehler manifold. I, J. Differential Geom. 16 (1981), no. 2, 305.322 https://doi.org/10.4310/jdg/1214436106
  3. B. Y. Chen, Geometry of Slant Submanifolds, Katholieke Universiteit Leuven, Louvain, 1990
  4. B. Y. Chen, Geometry of warped product CR-submanifolds in Kaehler manifolds, Monatsh. Math. 133 (2001), no. 3, 177.195 https://doi.org/10.1007/s006050170019
  5. B. Y. Chen, On isometric minimal immersions from warped products into real space forms, Proc. Edinb. Math. Soc. (2) 45 (2002), no. 3, 579.587 https://doi.org/10.1017/S001309150100075X
  6. B. Y. Chen, Another general inequality for CR-warped products in complex space forms, Hokkaido Math. J. 32 (2003), no. 2, 415.444 https://doi.org/10.14492/hokmj/1350657533
  7. N. Ejiri, Some compact hypersurfaces of constant scalar curvature in a sphere, J. Geom. 19 (1982), no. 2, 197.199 https://doi.org/10.1007/BF01930880
  8. I. Hasegawa and I. Mihai, Contact CR-warped product submanifolds in Sasakian manifolds, Geom. Dedicata 102 (2003), 143.150 https://doi.org/10.1023/B:GEOM.0000006582.29685.22
  9. S. Hiepko, Eine innere Kennzeichnung der verzerrten Produkte, Math. Ann. 241 (1979), no. 3, 209.215 https://doi.org/10.1007/BF01421206
  10. K. A. Khan, V. A. Khan, and S. I. Husain, On the integrability of the distributions on a CR-submanifold, An. Stiint. Univ. Al. I. Cuza Iasi Sect. I a Mat. 38 (1992), no. 4, 367.378
  11. K. A. Khan, V. A. Khan, and S. I. Husain, Totally umbilical CR-submanifolds of nearly K¨ahler manifolds, Geom. Dedicata 50 (1994), no. 1, 47.51 https://doi.org/10.1007/BF01263650
  12. V. A. Khan, K. A. Khan, and Saraj Uddin, Warped product CR-submanifolds of a nearly Kaehler manifold, SUT Journal of Math. 43 (2007), no. 2, 201.213
  13. B. Sahin, Nonexistence of warped product semi-slant submanifolds of Kaehler manifolds, Geom. Dedicata 117 (2006), 195.202 https://doi.org/10.1007/s10711-005-9023-2
  14. K. Sekigawa, Some CR-submanifolds in a 6-dimensional sphere, Tensor (N.S.) 41 (1984), no. 1, 13.20
  15. F. Urbano, CR-submanifolds of nearly Kaehler manifolds, Doctorial Thesis, Granada, 1980

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  2. Geometry of Warped Product Semi-Slant Submanifolds of Nearly Kaehler Manifolds vol.71, pp.3-4, 2017, https://doi.org/10.1007/s00025-016-0581-4
  3. Geometry of warped product lightlike submanifolds of indefinite nearly Kaehler manifolds vol.109, pp.1, 2018, https://doi.org/10.1007/s00022-018-0425-3
  4. Semi-invariant warped product submanifolds of almost contact manifolds vol.2012, pp.1, 2012, https://doi.org/10.1186/1029-242X-2012-127