Curve lower bound from a homogeneous section test
OpenOAI.MaximalSeshadri.Geometry.curve_lower_of_homogeneous_section_testLet be ample on , , a configuration, affine with a trivialization of , and suppose that for all with some -points of over have the property that every section of with coefficient in for all vanishes. Then for each integral curve .
Notation. is selfIntersection, namely . is curveDegree, namely . is totalMultiplicity, the sum over the points of curveMultiplicity, the order of the kernel ideal of the local ring map of at the point. IsAmple means that for each point and open , some positive power has a global section with nonvanishing open containing , inside , and affine. A Surface is an integral scheme smooth of relative dimension 2 over with a closed immersion into some complex projective space over . An IntegralCurve on a surface is an integral closed subscheme of topological Krull dimension one, given by a closed immersion. Configuration S r is the set of -tuples of complex points with distinct images, with the Zariski topology induced from the product.
Formalization Note The statement is verbatim from OpenAI's Lean development, with Definitions files of this development imported in place of the upstream modules; these are supporting code for the statement.
import Mathlib import Definitions.Def_MaximalSeshadriConstants import Definitions.Def_SeshadriPrelim6 namespace OAI section namespace MaximalSeshadri.Geometry noncomputable section open AlgebraicGeometry CategoryTheory TopologicalSpace open MaximalSeshadri.Frames MaximalSeshadri.ProjectiveBertini
theorem curve_lower_of_homogeneous_section_test (S : Surface)
(L : LineBundle S.scheme) (hL : L.IsAmple) {r : ℕ} (hr : 0 < r)
(p : Configuration S r) (U : S.scheme.affineOpens)
(eL : L.sheaf.restrict U.1.ι ≅ O U.1.toScheme)
(htest : ∀ k m : ℕ, 0 < k → 0 < m →
(k:ℝ)*Real.sqrt ((selfIntersection S L:ℝ)/r) < (m:ℝ) →
∃ ρ : letI := (openScalars S.structureMap U.1).toAlgebra;
Fin r → (Γ(S.scheme,U.1) →ₐ[ℂ] ℂ),
(∀ i, affineComplexPoint S.structureMap U (ρ i) = p.val i) ∧
∀ s : O S.scheme ⟶ (L.pow k).sheaf,
(∀ i, affineCoefficient U (localPowerFrame U.1 eL k) s ∈
(RingHom.ker (ρ i))^m) → s = 0)
(C : IntegralCurve S) :
Real.sqrt ((selfIntersection S L:ℝ)/r) * (totalMultiplicity S r C p:ℝ) ≤
(curveDegree S L C:ℝ) := by
sorry
end
end MaximalSeshadri.Geometry
end
end OAI