Abstract
We study projective curvature tensor in K-contact and Sasakian manifolds. We prove that (1) if a K-contact manifold is quasi projectively flat then it is Einstein and (2) a K-contact manifold is ξ-projectively flat if and only if it is Einstein Sasakian. Necessary and sufficient conditions for a K-contact manifold to be quasi projectively flat and φ-projectively flat are obtained. We also prove that for a (2n + 1)-dimensional Sasakian manifold the conditions of being quasi projectively flat, φ-projectively flat and locally isometric to the unit sphere S 2n+1 (1) are equivalent. Finally, we prove that a compact φ-projectively flat K-contact manifold with regular contact vector field is a principal S 1-bundle over an almost Kaehler space of constant holomorphic sectional curvature 4.
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Tripathi, M.M., Dwivedi, M.K. The structure of some classes of K-contact manifolds. Proc Math Sci 118, 371–379 (2008). https://doi.org/10.1007/s12044-008-0029-1
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DOI: https://doi.org/10.1007/s12044-008-0029-1