Results 11 to 20 of about 57 (57)
A Kähler Einstein structure on the tangent bundle of a space form
International Journal of Mathematics and Mathematical Sciences, Volume 25, Issue 3, Page 183-195, 2001., 2001 We obtain a Kähler Einstein structure on the tangent bundle of a Riemannian manifold of constant negative curvature. Moreover, the holomorphic sectional curvature of this Kähler Einstein structure is constant. Similar results are obtained for a tube around zero section in the tangent bundle, in the case of the Riemannian manifolds of constant positive ...
Vasile Oproiu
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A Family of Complex Nilmanifolds with in finitely Many Real Homotopy Types
Complex Manifolds, 2018 We find a one-parameter family of non-isomorphic nilpotent Lie algebras ga, with a > [0,∞), of real dimension eight with (strongly non-nilpotent) complex structures.
Latorre Adela +2 more
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Totally real submanifolds in a complex projective space
International Journal of Mathematics and Mathematical Sciences, Volume 22, Issue 1, Page 205-208, 1999., 1999 In this paper, we establish the following result: Let M be an n‐dimensional complete totally real minimal submanifold immersed in CPn with Ricci curvature bounded from below. Then either M is totally geodesic or inf r ≤ (3n + 1)(n − 2)/3, where r is the scalar curvature of M.
Liu Ximin
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On some compact almost Kähler locally symmetric space
International Journal of Mathematics and Mathematical Sciences, Volume 21, Issue 1, Page 69-72, 1998., 1997 In the framework of studying the integrability of almost Kähler manifolds, we prove that if a compact almost Kähler locally symmetric space M is a weakly ,∗‐Einstein vnanifold with non‐negative ,∗‐scalar curvature, then M is a Kähler manifold.
Takashi Oguro
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On CR‐submanifolds of the six‐dimensional sphere
International Journal of Mathematics and Mathematical Sciences, Volume 18, Issue 1, Page 201-203, 1995., 1995 We consider proper CR‐submanifolds of the six‐dimensional sphere S6. We prove that S6 does not admit compact proper CR‐submanifolds with non‐negative sectional curvature and integrable holomorphic distribution.
M. A. Bashir
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CR‐hypersurfaces of the six‐dimensional sphere
International Journal of Mathematics and Mathematical Sciences, Volume 17, Issue 1, Page 197-200, 1994., 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. We also proved that an Einstein proper CR‐hypersurface of S6 is an extrinsic sphere.
M. A. Bashir
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Kähler metrics via Lorentzian Geometry in dimension four
Complex Manifolds, 2019 Given a semi-Riemannian 4-manifold (M, g) with two distinguished vector fields satisfying properties determined by their shear, twist and various Lie bracket relations, a family of Kähler metrics gK is constructed, defined on an open set in M, which ...
Aazami Amir Babak, Maschler Gideon
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Deformation classes in generalized Kähler geometry
Complex Manifolds, 2020 We describe natural deformation classes of generalized Kähler structures using the Courant symmetry group, which determine natural extensions of the notions of Kähler class and Kähler cone to generalized Kähler geometry.
Gibson Matthew, Streets Jeffrey
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CR‐hypersurfaces of complex projective space
International Journal of Mathematics and Mathematical Sciences, Volume 17, Issue 3, Page 613-616, 1994., 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 less than or equal to n − 1.
M. A. Bashir
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Contact manifolds, Lagrangian Grassmannians and PDEs
Complex Manifolds, 2018 In this paper we review a geometric approach to PDEs. We mainly focus on scalar PDEs in n independent variables and one dependent variable of order one and two, by insisting on the underlying (2n + 1)-dimensional contact manifold and the so-called ...
Eshkobilov Olimjon +3 more
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