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تسجيل مستخدم جديدContact Pairs
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We introduce a new geometric structure on differentiable manifolds. A textit{Contact} textit{Pair}on a manifold $M$ is a pair $(alpha,eta) $ of Pfaffian forms of constant classes $2k+1$ and $2h+1$ respectively such that $alphawedge dalpha^{k}wedgeetawedge deta^{h}$ is a volume form. Both forms have a characteristic foliation whose leaves are contact manifolds. These foliations are transverse and complementary. Further differential objects are associated to Contact Pairs: two commuting Reeb vector fields, Legendrian curves on $M$ and two Lie brackets on $mathcal{C}^{infty}(M) $. We give a local model and several existence theorems on nilpotent Lie groups, nilmanifolds, bundles over the circle and principal torus bundles.
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