3 problems

Let $(M,\mathcal{I})$ be an involutive exterior differential system. Let $\dot{\Xi}$ and $\Xi_E$ be the characteristic varieties defined in the surrounding discussion, viewed as su…

Let $(M,\mathcal{I})$ be an involutive exterior differential system. Let $E$ and $\dot{A}$ denote the tableaux introduced in the surrounding discussion, and let their characteristi…

Let $(M,\mathcal{I})$ be an analytic involutive exterior differential system, considered over $\mathbb{C}$. Write $\operatorname{elem}(\mathcal{I})$ for its elementary system, and…