Andreotti–Frankel theorem

The Andreotti–Frankel theorem is a result in complex geometry, specifically in the context of Stein manifolds and the topology of complex spaces. The theorem is named after the mathematicians A. Andreotti and T. Frankel, who formulated it in the 1960s. The essential statement of the Andreotti–Frankel theorem pertains to the existence of non-trivial holomorphic (complex) forms on certain types of complex manifolds.