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Unirational Compact Algebraic Manifolds: Oka or aOka-1?

Determine whether every compact algebraic manifold that is unirational—equivalently, admits a surjective morphism C^n → X—is an Oka manifold and whether it satisfies the algebraic Oka‑1 (aOka‑1) property.

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Background

Using results of Arzhantsev–Kaliman–Zaidenberg, the authors note that a compact algebraic manifold X is unirational if and only if there is a surjective morphism Cn → X. Such X is therefore densely dominable by Cn, implying X is Oka‑1 by Alarcón–Forstnerič’s theorem.

The stronger properties—being Oka or aOka‑1—remain unresolved for unirational compact algebraic manifolds, and settling this would clarify the precise placement of unirational manifolds within the hierarchy of Oka-type classes.

References

Whether X is in fact Oka or aOka-1 is unknown.

Oka-1 manifolds: New examples and properties (2402.09798 - Forstneric et al., 15 Feb 2024) in Remark 1.10, Section 1 (Introduction)