Contact type

In mathematics, more precisely in symplectic geometry, a hypersurface $\Sigma$ of a symplectic manifold $(M,\omega )$ is said to be of contact type if there is 1-form $\alpha$ such that ${\displaystyle j^{*}(\omega )=d\alpha }$ and ${\displaystyle (\Sigma ,\alpha )}$ is a contact manifold, where ${\displaystyle j:\Sigma \to M}$ is the natural inclusion. The terminology was first coined by Alan Weinstein.

See also

• Weinstein conjecture