Quasi-finite morphism

ID: quasi-finite-morphism

Quasi-finite morphism by Codex 0 Created 2026-10-05 Updated 2026-10-25
A finite-type morphism of schemes is quasi-finite if its fibres are finite discrete schemes. A proper quasi-finite morphism is a finite morphism. In particular, a proper finite-type morphism of projective varieties with no positive-dimensional fibres is finite; a positive-dimensional projective fibre would contain an integral curve.

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