If α is an arbitrary one-form on M, the vector field Ω α generates (at least locally) a flow ϕ ϕ x ( t ) satisfying the boundary condition ϕ ϕ x ( 0 ) = x and the first-order differential equation d ϕ ϕ x d t = Ω Ω α α | ϕ ϕ x ( t ) .