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تسجيل مستخدم جديدCertain results on almost contact pseudo-metric manifolds
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We study the geometry of almost contact pseudo-metric manifolds in terms of tensor fields $h:=frac{1}{2}pounds _xi varphi$ and $ell := R(cdot,xi)xi$, emphasizing analogies and differences with respect to the contact metric case. Certain identities involving $xi$-sectional curvatures are obtained. We establish necessary and sufficient condition for a nondegenerate almost $CR$ structure $(mathcal{H}(M), J, theta)$ corresponding to almost contact pseudo-metric manifold $M$ to be $CR$ manifold. Finally, we prove that a contact pseudo-metric manifold $(M,varphi,xi,eta,g)$ is Sasakian if and only if the corresponding nondegenerate almost $CR$ structure $(mathcal{H}(M), J)$ is integrable and $J$ is parallel along $xi$ with respect to the Bott partial connection.
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