--- date: 2022-09-05 14:04 modification date: Monday 5th September 2022 14:04:40 title: "Chow's theorem" aliases: [Chow's theorem] --- Last modified date: <%+ tp.file.last_modified_date() %> --- - Tags: - #AG/complex - Refs: - #todo/add-references - Links: - #todo/create-links --- # Chow's theorem - If $X \subseteq \PP^n$ is a closed analytic subspace, then $X$ is is a projective subscheme. - In general, for an algebraic scheme $(X, \OO_X)$ of ft over $\CC$, one can construct an analytic variety $(X^\an, \OO_{X}^\an)$ by essentially throwing away non-closed points and enriching the topology. - This yields a functor that induces an equivalence between projective schemes and compact analytic subschemes of $\PP^N$. - Idea why: a morphisms of schemes or analytic spaces is represented by its graph, which embeds in the product. So if the domain/range are both projective, so is the graph. - $\CC$ has many holomorphic functions that are far from algebraic, so that $X$ is an analytic closed subset is necessary.