Results 1 to 10 of about 136 (132)
Normal holonomy of CR submanifolds
, 2013 We study the normal holonomy group, i.e. the holonomy group of the normal connection, of a CR-submanifold of a complex space form. We show that the normal holonomy group of a coisotropic submanifold acts as the holonomy representation of a Riemannian symmetric space.
Vittone, Francisco, Di Scala, Antonio J.
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CR submanifolds of a Kaehler manifold. II [PDF]
Transactions of the American Mathematical Society, 1978 The differential geometry of CR submanifolds of a Kaehler manifold is studied. Theorems on parallel normal sections and on a special type of flatness of the normal connection on a CR submanifold are obtained. Also, the nonexistence of totally umbilical proper CR submanifolds in an elliptic or hyperbolic complex space is proven.
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Mathematics, 2019 The purpose of this article is to obtain geometric conditions in terms of gradient Ricci curvature, both necessary and sufficient, for a warped product semi-slant in a Kenmotsu space form, to be either CR-warped product or simply a Riemannian product ...
Ali H. Alkhaldi, Akram Ali
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Totally umbilical CR-submanifolds of Semi-Riemannian Kaehler manifolds
International Journal of Mathematics and Mathematical Sciences, 1987 We study totally umbilical CR-submanifolds of a Kaehler manifold carrying a semi-Riemannian metric. It is shown that for dimension of the totally real distribution greater than one, these submanifolds are locally decomposable into a complex and a totally
K. L. Duggal, R. Sharma
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GEOMETRIC INEQUALITIES FOR CR-SUBMANIFOLDS
Facta Universitatis, Series: Mathematics and InformaticsWe study two kinds of curvature invariants of Riemannian manifold equipped with a complex distribution D (for example, a CR-submanifold of an almost Hermitian manifold) related to sets of pairwise orthogonal subspaces of the distribution. One kind of invariant is based on the mutual curvature of the subspaces and another is similar to Chen’s δ ...
Mirjana Djorić, Vladimir Rovenski
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Semi-invariant submanifolds of (g, F)-manifolds [PDF]
Surveys in Mathematics and its Applications, 2010 We introduce (g,F)-manifolds and initiate a study of their semi-invariant submanifolds. These submanifolds are generalizations of CR-submanifolds of Kaehler manifolds.
Novac-Claudiu Chiriac
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Space time manifolds and contact structures
International Journal of Mathematics and Mathematical Sciences, 1990 A new class of contact manifolds (carring a global non-vanishing timelike vector field) is introduced to establish a relation between spacetime manifolds and contact structures.
K. L. Duggal
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CR-hypersurfaces of complex projective space
International Journal of Mathematics and Mathematical Sciences, 1994 We consider compact n-dimensional minimal foliate CR-real submanifolds of a complex projective space. We show that these submanifolds are great circles on a 2-dimensional sphere provided that the square of the length of the second fundamental form is ...
M. A. Bashir
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CR-hypersurfaces of the six-dimensional sphere
International Journal of Mathematics and Mathematical Sciences, 1994 We proved that there does not exist a proper CR-hypersurface of S6 with parallel second fundamental form. As a result of this we showed that S6 does not admit a proper CR-totally umbilical hypersurface.
M. A. Bashir
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Chen's problem on mixed foliate CR-submanifolds [PDF]
Bulletin of the Australian Mathematical Society, 1989 We prove that the simply connected compact mixed foliate CR-submanifold in a hyperbolic complex space form is either a complex submanifold or a totally real submanifold. This is the problem posed by Chen.
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