Cartan–Kuranishi prolongation theorem

Given an exterior differential system defined on a manifold M, the Cartan–Kuranishi prolongation theorem says that after a finite number of prolongations the system is either in involution (admits at least one 'large' integral manifold), or is impossible.

The theorem is named after Élie Cartan and Masatake Kuranishi.

This theorem is used in infinite-dimensional Lie theory.

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