A δ -Invariant for QR-Submanifolds in Quaternion Space Forms

A δ -Invariant for QR-Submanifolds in Quaternion Space Forms

Starting from an inequality involving the invariant δ(D) for an anti-holomorphic submanifold ofa complex space form [1] and using optimization methods on Riemannian manifolds, we establisha corresponding inequality for the invariant δ(D ⊥ ) defined on QR-submanifolds in quaternionspace forms, in terms of the squared mean curvature. We obtain a relationship between intrinsicand extrinsic invariants for QR-submanifolds of quaternion space forms.

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  • Al-Solamy, F., Chen, B.-Y. and Deshmukh, S., Two optimal inequalities for anti-holomorphic submanifolds and their applications, Taiwanese J. Math. 18 (2014), no.1, 199-217.
  • Bejancu, A., QR-submanifolds of quaternion Kaehler manifolds, Chinese J. Math. 14 (1986), no. 2, 81-94.
  • Chen, B.-Y., CR-submanifolds of a Kaehler manifold, J. Diff. Geom. 16 (1981), 305-323.
  • Chen, B.-Y., An optimal inequality for CR-warped products in complex space forms involving CR δ-invariant, Internat. J. Math. 23 (2012), no. 3, 1250045 (17 pages).
  • Macsim, G. and Mihai, A., An inequality on quaternionic CR-submanifolds, Ann. Univ. Ovidius Constanţa, XXVI (2018), no. 3, to appear.
  • Nash, J. F., The imbedding problem for Riemannian manifolds, Ann. of Math. 63 (1956), 20-63.
  • Oprea, T., Optimizations on Riemannian submanifolds, Analele Univ. Buc. LIV 1 (2005), 127-136.
  • Şahin, B., On QR-submanifolds of a quaternionic space forms, Turkish J. Math. 25 (2001), 413-425.