Contact distribution symplectic form
= Contact distribution symplectic form
{title2=$d\alpha|_\xi$}
For a <contact form> on a $(2r+1)$-manifold, $d\alpha|_{\ker\alpha}$ is <nondegenerate>: the contact condition says its top exterior power is nowhere zero on the hyperplanes. This fiberwise <symplectic form> identifies contact-plane vectors with covectors on that plane and determines the <horizontal generator of contact stability>.