• $\nabla$ is topologically quasi-nilpotent: If we write $\nabla (m) = \sum \theta _ i(m)\text{d}x_ i$ for some operators $\theta _ i : M \to M$, then for any $m \in M$ there are only finitely many pairs $(i, k)$ such that $\theta _ i^ k(m) \not\in pM$.

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