2 problems

Let $A$ be a smooth unbendable rational curve in a complex manifold $X$. The curve $A$ satisfies the formal principle: whenever a compact complex submanifold $\widetilde{A}$ in a c…

Let $X$ be a complex manifold and let ${\mathcal K}$ be a connected family of smooth rational curves on $X$ with semipositive normal bundles. The family is bracket-generating when…